Prevention and Control of Powdery Mildew

Understanding which plants are prone to powdery mildew and why others are resistant can help you make informed decisions about what to plant in your garden and how to manage those that are susceptible. By choosing resistant varieties and maintaining good cultural practices, you can minimize the impact of powdery mildew in your garden.

Prevention of Powdery Mildew

1. Choose Resistant Varieties: Select plant varieties that are resistant or less susceptible to powdery mildew.

2. Proper Spacing: Ensure adequate spacing between plants to improve air circulation, which helps to reduce humidity levels around the foliage.

3. Watering Practices:

   • Water plants at the base, avoiding overhead watering, which can increase humidity and promote mildew growth.

   • Water early in the day to allow moisture on the plants to dry before evening.

4. Soil Management:

   • Keep the area around plants clean and free of debris, as organic matter can harbor the fungus.

   • Use well-draining soil to avoid excess moisture, which can contribute to mildew growth.

5. Mulching: Apply mulch around the base of plants to retain soil moisture and prevent splashing of water onto the leaves, which can spread spores.

6. Regular Monitoring: Inspect plants regularly, especially during periods of warm, dry weather followed by high humidity. Early detection can help prevent the spread.

Removal of Powdery Mildew

1. Prune Affected Areas:

   • Remove and destroy infected leaves, stems, or flowers as soon as you notice them.

   • Dispose of the infected plant material in the trash, not in compost, to prevent spreading the spores.

2. Natural Remedies:

   • Milk Spray: Mix 1 part milk with 2 parts water and spray the affected plants. Milk has natural anti-fungal properties.

   • Baking Soda Solution: Mix 1 tablespoon of baking soda, 1 teaspoon of liquid soap, and 1 gallon of water. Spray this solution on affected plants to kill the mildew.

3. Fungicides:

   • Edible Plants: Apply an organic fungicide, such as neem oil or sulfur-based products. These are effective and safe for edible plants.When treating edible plants, especially those you will soon harvest, prioritize non-toxic, organic solutions like milk sprays, neem oil, or baking soda. Chemical fungicides should be used with caution, ensuring they are safe for food crops.

   • Ornamental Plants: While you can use the same organic methods, you have more flexibility with chemical treatments since there’s no concern about consumption. For severe cases, you may need to use a chemical fungicide, but ensure it’s labeled safe for the specific plants you're treating. However, still consider the environmental impact and safety, particularly if the ornamental plants are near edible gardens or frequented by pets or children.

4. Improve Air Circulation:

   • Thin out the foliage to allow better airflow around the plants, which can help reduce the humidity that powdery mildew thrives on.

   • Ensure plants are not overcrowded.

5. Maintain a Dry Environment:

   • Avoid watering in the evening to reduce the amount of time plants stay wet, as mildew thrives in humid, dark conditions.

   • Increase sunlight exposure if possible, as powdery mildew is less likely to thrive in direct sunlight.

Washing Off Powdery Mildew

If you want to preserve as many leaves as possible, you can gently wash off the powdery mildew from the least affected leaves instead of removing them entirely. Choose a time when the plants are not exposed to direct sunlight, such as early morning or late afternoon. This prevents the leaves from getting sunburned after washing.

1. Prepare a mild solution using one of the following options:

   • Water and Baking Soda Solution: Mix 1 tablespoon of baking soda with 1 gallon of water. This helps to neutralize the mildew and prevent further spread.

   • Water and Dish Soap Solution: Mix a few drops of mild liquid soap (not detergent) with 1 gallon of water. The soap helps break down the mildew and makes it easier to wash off.

   • Water and Milk Solution: Mix 1 part milk with 2 parts water. Milk has natural antifungal properties and is gentle on the leaves.

2. Washing the Leaves:

   • Dip a soft cloth, sponge, or spray bottle into the solution.

   • Gently wipe or spray the affected leaves, focusing on the areas with visible mildew. Be careful not to scrub too hard, as this can damage the leaves.

   • If using a spray, ensure you thoroughly cover the affected areas, allowing the solution to sit for a few minutes.

3. Rinsing:

   • After wiping or spraying, rinse the leaves with clean water to remove any residue from the solution.

   • You can use a gentle spray from a garden hose or a watering can to do this.

4. Drying:

   • Allow the leaves to air dry naturally. Make sure there is good airflow around the plants to speed up the drying process and prevent further mildew growth.

   • Avoid watering the plants from above until the leaves are completely dry.

5. Follow-Up Care:

   • Monitor the leaves over the next few days. If you notice any new mildew spots, you may need to repeat the washing process.

   • Ensure the plants are in an environment with good air circulation and proper sunlight to help prevent future mildew outbreaks.

Plants Prone to Powdery Mildew

Powdery mildew is a common fungal disease that affects a wide variety of plants. Some of the most susceptible plants include:

1. Vegetables:

   • Cucurbits: Cucumbers, pumpkins, squash, and zucchini.

   • Tomatoes: Especially in humid conditions.

   • Peppers: Both hot and sweet varieties.

   • Beans: Particularly pole beans.

2. Fruits:

   • Grapes: Both wine and table varieties are prone to powdery mildew.

   • Apples and Pears: Especially in humid climates.

   • Strawberries: Can be affected under certain conditions.

3. Ornamentals:

   • Roses: Very susceptible to powdery mildew, particularly in humid environments.

   • Lilacs: Often affected, especially in areas with poor air circulation.

   • Zinnias and Phlox: Commonly get powdery mildew in gardens.

   • Begonias: Susceptible in both outdoor and indoor environments.

4. Trees and Shrubs:

   • Dogwoods: Particularly in shady, damp areas.

   • Oaks: Some species are prone, especially in moist conditions.

   • Maples: Certain varieties can be affected.

5. Proper Care and Maintenance: Plants that are well-cared for, with proper watering, fertilization, and pruning, are generally more resilient to diseases, including powdery mildew. Healthy plants can often fend off or recover from infections more effectively than stressed or neglected ones.

“Grow Your Own Food” blog posts

See the full list of our Grow Your Own Food blog posts. Each post is assigned ”tags” which are under the post title. If you need a quick answer to a gardening question give us a call or send a text to our customer support team – support[at]deep-roots-project.org AND 708-655-5299.

Deep Roots online store

See our online store for details about prices, ordering and delivery of raised beds, planter boxes, microbe-rich compost, worm castings, leaf mulch and more. We don’t sell traditional soil, since we use 100% compost as our growing medium. Our online store has 2 sections – (1) raised beds and planter boxes and (2) compost, worm castings, fertilizer.

Please contact our customer support team before placing an order online so we can assist you with the details and answer your gardening questions. You can pay by credit card in the store or by check.

(708) 655-5299 and support[at]deep-roots-project.org

Please leave your cell phone number when you sign up for our eNewsletter, if you want text message announcements now and then. 

Donations help us provide organic kitchen gardening education to individuals, organizations, and entire communities. Thank you in advance for contributing to our community and for sharing our website and blog with friends and family.

Protection from the Squash Vine Borer

By following these instructions, you can effectively protect your squash plants from the squash vine borer moth and its caterpillar, ensuring a healthy and bountiful harvest. Trombocino squash is an Italian heirloom that provides it own natural protection against this pest because of it very hard lower stem.

Summary:

Here are detailed instructions for protecting a squash seedling from the squash vine borer moth and caterpillar using the plastic cup method. A small plastic flower pot or plastic cup is placed around the root ball of a seedling before it is planted in the ground.

The bottom of the pot or cup must be removed with scissors. The side must be slit also so the pot or cup can be wrapped around the root. The cup is partially under the soil and partially above the soil. Bug netting can also protect the plant from the moth laying its eggs on or near the plant. The cup protects the lower stem from the caterpillar boring inside the stem.

Materials needed:

• Small plastic flower pot or plastic cup

• Scissors

• Bug netting (optional)

• Squash seedlings

• Gardening trowel

• Soil

Instructions:

1. Prepare the plastic cup or small flower pot:

   • Remove the Bottom: Use scissors to cut out the bottom of the plastic cup or flower pot. This creates an open cylinder that will allow the plant’s roots to grow into the soil.

   • Slit the Side: Make a vertical cut from the top to the bottom of the cup. This slit will enable you to wrap the cup around the root ball of the seedling.

2. Prepare the seedling:
   Carefully remove the squash seedling from its nursery container, ensuring you keep the root ball intact.

3. Place the cup around the root ball:
   Gently wrap the prepared plastic cup around the root ball of the seedling. The slit should allow you to easily encircle the root without damaging it.

4. Plant the seedling:

   • Dig a hole in your garden bed that is deep enough to accommodate the root ball and the plastic cup.

   • Place the seedling, with the plastic cup around its root ball, into the hole. Ensure that the cup is partially buried under the soil and partially above the soil. The buried part will protect the roots and lower stem, while the exposed part will prevent the squash vine borer moth from laying eggs near the base of the plant.

5. Secure the cup:

   • Firmly press the soil around the base of the plastic cup to keep it in place. Ensure that the cup stands upright and does not tip over.

   • The cup should protrude about 2-3 inches above the soil surface. This barrier will help protect the lower stem from the caterpillars boring inside.

6. Optional: apply bug netting:

   • To provide additional protection, you can cover the entire plant with bug netting. This will prevent the moth from reaching the plant to lay eggs.

   • Secure the netting tightly around the base of the plant, ensuring there are no gaps where the moth can enter.

   • Check regularly to ensure the netting is still secure and the plant has enough space to grow.

7. Regular monitoring:

   • Regularly inspect the plant for any signs of squash vine borer activity or damage. Look for small holes at the base of the stem, frass (sawdust-like debris), and wilting leaves.

   • If you notice any signs of infestation, take immediate action to remove the caterpillars manually and treat the plant with appropriate organic pesticides if necessary.

“Grow Your Own Food” blog posts

See the full list of our Grow Your Own Food blog posts. Each post is assigned ”tags” which are under the post title. If you need a quick answer to a gardening question give us a call or send a text to our customer support team – support[at]deep-roots-project.org AND 708-655-5299.

Deep Roots online store

See our online store for details about prices, ordering and delivery of raised beds, planter boxes, microbe-rich compost, worm castings, leaf mulch and more. We don’t sell traditional soil, since we use 100% compost as our growing medium. Our online store has 2 sections – (1) raised beds and planter boxes and (2) compost, worm castings, fertilizer.

Please contact our customer support team before placing an order online so we can assist you with the details and answer your gardening questions. You can pay by credit card in the store or by check.

(708) 655-5299 and support[at]deep-roots-project.org

Please leave your cell phone number when you sign up for our eNewsletter, if you want text message announcements now and then.

Donations help us provide organic kitchen gardening education to individuals, organizations, and entire communities. Thank you in advance for contributing to our community and for sharing our website and blog with friends and family.

Growing and Using Comfrey

Comfrey (Symphytum officinale) has been used for centuries in herbal medicine, but its use comes with significant safety concerns. The primary concern is the presence of pyrrolizidine alkaloids (PAs), which can cause severe liver damage and are potentially carcinogenic. (Searched 4 sites)

Safe Uses of Comfrey

Topical Applications:

Wound Healing and Skin Conditions: Comfrey can be used safely on unbroken skin for treating wounds, bruises, sprains, and other minor injuries. It is often used in the form of poultices, salves, and ointments. However, it should not be applied to broken skin or used for more than 10 days in a row to avoid absorption of harmful PAs (Drugs.com) (SPICEography) .

Gardening:

Fertilizer: Comfrey leaves are rich in nutrients like nitrogen, phosphorus, and potassium, making them excellent for use as a natural fertilizer. The leaves can be steeped in water to create a liquid fertilizer or added directly to compost (Common Sense Home).

Unsafe Uses of Comfrey

Internal Use:

Ingesting Comfrey: Consuming comfrey, whether as a tea, in salads, or in other foods, is generally considered unsafe due to the risk of liver damage and other serious health issues. The PAs present in comfrey can accumulate in the liver and cause veno-occlusive disease, leading to liver failure and potentially cancer (Drugs.com) (SPICEography) .

Conclusion

While comfrey can be beneficial for certain topical applications and in gardening, it is not safe for internal consumption due to the high risk of liver toxicity and other serious health problems. It is always best to consult with a healthcare provider before using comfrey, especially if you have underlying health conditions or are taking other medications.

Swede Midge Fly Management

Suburban organic gardeners in Illinois usually protect their Brassica crops (kale, collards, cabbage, etc.) from cabbage moths and their caterpillars. But, brace yourselves for a new Brassica family pest challenge – the tiny Swede Midge fly. There are conventional toxic pesticide sprays that do control and prevent swede midge that we can’t use in our organic gardens. Deep Roots consulted with the Chicago Botanic Garden Plant Information Service about the best non-toxic solutions.

Protect Collards, Kale & Cabbage from Pests

The swede midge fly (Contarinia nasturtii), an invasive pest from Europe, has begun wreaking havoc on brassica crops. including radish, horseradish, rutabaga, turnip, rapeseed (canola), arugula, bok choy and Chinese cabbage. Crops that are most damaged include common favorites such as broccoli, cauliflower, cabbage, kale, kohlrabi, collards and Brussels sprouts.

Swede midge are very tiny lightweight flies that can spread long distances by the wind. Their life cycle is between May to October in Zones 5 and 6 (Chicagoland area). The first year or so of its presence often goes unnoticed, but un-recognized populations can quickly build up and devastate brassica crops. There are conventional toxic pesticide sprays that do control and prevent swede midge that we can’t use in our organic gardens.

Swede midge is a pest in many parts of the northeastern United States, including New York, Vermont, and New Hampshire. It has also been found in Minnesota, Illinois, and Wisconsin. 

Understanding the swede midge life cycle

We expect the swede midge will find our collards kale and cabbage. Once the damage is visible there is no way to save the plant. Cut down the plant stem at the soil and put in the garbage – not the compost bin.

In the Chicago area, encompassing USDA Hardiness Zones 5b and 6a, adult swede midge (Contarinia nasturtii) typically begin to emerge from overwintering pupae in May . This emergence marks the start of their active period, which extends through October, during which they can produce multiple overlapping generations 

The fly’s life cycle repeats about 5 times every growing season. Adult flies live for a few days, just long enough to reproduce and lay 2 to 50 eggs on the newest growth points of a Brassica host plant. The emerging larvae (maggots) feed by secreting digestive enzymes, damaging the plant’s growing points and causing deformities or preventing proper head formation.

After the maggots are well fed and fully grown, they dive into the top inch of soil to pupate – transform back into a fly. They emerge from the soil as adult flies within a week or two, depending upon soil temperature and moisture, and start the cycle over again. But if buried below 2 inches, the pupae can survive for two years and can emerge if digging or tilling brings them higher up at a later time.

Identifying swede midge damage

In the worst cases, damage to single-stemmed heading brassica crops such as broccoli, cauliflower and cabbage looks as if the plants have been pinched back, preventing a single large head from forming. Because feeding damage can vary greatly depending on where the larvae feed on the plant and on the stage of plant development, it can be confused with many other issues.

Eat the unaffected collard, kale and cabbage leaves

This method has been approved by the Chicago Botanical Garden Plant Information Service (847-835-0972). If a collard, kale and cabbage plant is infested with swede midge, you might still consider eating the unaffected leaves, but it's essential to take a few precautions. Make sure the leaves are thoroughly cleaned and cooked to minimize any potential risks associated with the infestation. Here are some steps to consider if you want to eat the unaffected leaves:

1. Inspect the whole plant: Carefully cut off any infected stems or parts.

2. Inspect the leaves: Carefully check the leaves for any signs of damage or presence of larvae. The larvae are very small and might not be immediately visible to the naked eye.

3. Wash thoroughly: Even if some leaves appear unaffected, wash them thoroughly in water, possibly with a mild soap solution, to remove any larvae or eggs that might be present.

4. Cook the leaves: Cooking can help ensure that any remaining insects or pathogens are killed. It's generally safer to eat cooked leaves than raw, especially if there's a chance they've been exposed to pests.

5. Monitor the plant: Keep an eye on the plant for further signs of infestation. If the infestation is severe, it might be better to remove and destroy the affected plant to prevent the pests from spreading.

6. Remove a plant without pulling the root in order to keep the healthy soil microbes in the soil. Not disturbing the soil as much as possible is a basic principle of our regenerative gardening method. Pull out the roots of only root crops like beets.

Recommendations for successful organic food harvest

Until agricultural scientists find an effective and simple way to organically and safely prevent or control swede midge. You won’t know if swede midge has already infected your soil before you plant. Deep Roots have suggestions for new growing seasons.

1. Protect a few collards, kale and cabbage plants with bug netting. See below details for a few options and links to videos.

2. It’s risky to buy seedlings from a garden center since they could be already infected by swede midge. Only buy them if they have been stored indoors.

3. DON’T grow Brassica crops this year. Substitute other leafy greens and veggies. Three suggestions

   • Grow regular spinach which must be started from seed. Best to plant the seeds in November.

   • Grow Red Malabar Spinach from seed indoors to give it a head start. This leafy green veggie doesn’t look like normal spinach, but has a similar taste. Unlike normal spinach, it grows well through the warm summer season. Plant it when you plant summer crops like tomatoes. It’s a vine that winds around any structure, trellis or plant nearby. Give it a big tall trellis.

   • Buy Swiss Chard seedlings at garden centers. It grows through spring and summer. Eat the leaves and the stems. We usually add the leaves to a salad and make hummus from the stems.

   • Beet greens look and taste like Swiss Chard. Direct sow the seeds in spring

   • Other veggies to try are:

     • Lettuce (various types, including romaine, butterhead, and iceberg)

     • Fresh herbs (cilantro, dill, parsley, chives, etc.)

     • Green onion

     • Leek

     • Chicory, Endive, Escarole, Radicchio

     • Fennel

     • French Tarragon

     • Asparagus

     • Celery

Make physical barriers with bug netting:

You won’t know until you try to grow Brassicas if your soil is already infected. If your soil is NOT already infected, physical barriers are a crucial defense mechanism. Cover your brassica plants with fine insect netting throughout the growing season. Place small groups of Brassica family crops under bug netting bags, or cover your whole bed with bug netting.

Contact our customer support team about buying bug netting bags and sheets from us. The bug netting page is not yet on our store.

• Bug netting bags protect small groups of plants in a raised bed: Bags can be different heights. Learn more details in this video: Growing Georgia Southern Collards Greens about harvesting collard greens and protecting them with large 4 x 4 foot netting bags supported by garden stakes. Their system protects from cabbage worms and butterflies, since they haven’t yet been invaded by Swede Midge.
  -Tall Brassicas (like kale, collards): Since these plants can grow 4 to 5 feet tall, use larger bug netting bags designed for big fruiting plants. Support the netting with 2-3 wooden stakes inside the bag to prevent it from resting on the plants and potentially damaging them. Use stones, wood or garden staples to hold down the bottom of netting against the soil.
  -Short Brassicas (like cabbage): Use smaller bug netting bags suitable for their height. Or place sheets of bug netting on the plants supported by sticks or hoops made of bendable white PVC half-inch pipes, see our blog post Installing Hoops on Raised Beds.

• Bug netting on a cloth grow bag: Plant 2-3 collard plants in a cloth grow bag. Support the netting with a wooden stake or a wire hoop placed inside the bag to prevent it from resting on the plants. Put something soft at the top the stake so it doesn’t poke a hole in the netting,

• Bug netting supported by hoops: Cover your entire bed with a sheet of fine bug netting supported by hoops. You can use various materials for the hoops. The hoops can be pushed into the soil or attached to the raised bed frame. Learn more details in this video: How to Make Hoops for Raised Beds (4 Ways) and see our blog post Installing Hoops on Raised Beds.

• Bug netting attached to a hinged hoop house: Another option is to hinge a wooden rectangle to the top of your raised bed. Attach the hoops to the rectangle. Learn more details in this video: How to Build a Hinged Hoop House

Order Bug Netting and Bags from Deep Roots

You can order bug netting and bags from Deep Roots. We have not yet added an online store page for netting. To order call, text or email our customer support team – support[at]deep-roots-project.org AND 708-655-5299.

Other Brassica Family Pests

Please see our Brassica Family Pests and Diseases post for information about other Brassica family pests.

“Grow Your Own Food” blog posts

See the full list of our Grow Your Own Food blog posts. Each post is assigned ”tags” which are under the post title. If you need a quick answer to a gardening question give us a call or send a text to our customer support team – support[at]deep-roots-project.org AND 708-655-5299.

Deep Roots online store

See our online store for details about prices, ordering and delivery of raised beds, planter boxes, microbe-rich compost, worm castings, leaf mulch and more. We don’t sell traditional soil, since we use 100% compost as our growing medium. Our online store has 2 sections – (1) raised beds and planter boxes and (2) compost, worm castings, fertilizer.

Please contact our customer support team before placing an order online so we can assist you with the details and answer your gardening questions. You can pay by credit card in the store or by check.

(708) 655-5299 and support[at]deep-roots-project.org

Please leave your cell phone number when you sign up for our eNewsletter, if you want text message announcements now and then. 

Donations help us provide organic kitchen gardening education to individuals, organizations, and entire communities. Thank you in advance for contributing to our community and for sharing our website and blog with friends and family.

Environmental Pest Management (EPM)

Environmental Pest Management (EPM) for organic food gardening is responsible environmental stewardship. Although EPM is modeled after the older Integrated Pest Management (IPM), it doesn’t allow use of toxic chemicals that are banned under the USDA organic standards. Contact your local botanic garden information service OR state university agricultural extension for help in identifying and treating pests. But only use the organic safe sprays we recommend in this post.

Learn more about our growing method in two recently revised blog posts.

EPM is all about multi-tasking

EPM tools and methods suppress and marginalize pests, and don’t totally eliminate all pests forever.

Previous attempts to totally eliminate pests with toxic chemicals never worked. Beyond Pesticides has a webpage with all the diseases caused by toxic chemical pesticides.

The combined use of EPM tools and methods are far more effective than the tools individually. These tools have limited impact as solo treatments. But combining EPM practices will deliver substantial pest relief to your garden without jeopardizing our environment or humans. Examples of multiple care methods include selection of diseases resistant varieties, proper spacing for air circulation, siting plants for their specific light requirements, proper watering, crop rotation, and bio-diverse planting. Throughout the season remove any badly affected leaves, practice good sanitation in fall by removing plant material. Find further discussion on insect and disease prevention at the Organic Gardening in NC State Extension website.

Treat the whole garden and use all the EPM tools all the time. We provide details below about what sprays to use and the frequecy of use. Not all pest control measures apply to all conditions. If you have an extreme infestation call us for a recommendation about using high-potency organic sprays.

Regularly practice ALL EPM methods

EPM is an integrated package. It's important to regularly practice all EPM methods.

Preventing pests and diseases will be far easier than managing them later. If you use all the EPM tools regularly you will have a major reduction in pests and diseases throughout the season. Spraying organic pesticides and fungicides regularly is only one supporting tool and will not be fully effective alone. Respect and practice all the parts of EPM as one tightly integrated system, so eventually they become habits that you are accustomed to and enjoy doing.

Pest prevention with a bio-diverse garden at its core is the key to success for your plants, your harvest and your enjoyment of gardening. Biodiversity planting is the foundation of EPM. Practicing EPM without a bio-diverse garden will be only partially effective - not the full protection you need for a flourishing garden and peace of mind. Learn more about practical steps of biodiversity and succession planting.

The entire EPM system has universal applications in every region and climate zone. Contact your local agricultural extension or botanic garden information service for help if you see a persistent pest problem.

Planting for biodiversity

Mass plantings of a single crop increases the vulnerability of the plants to insect pests and diseases. A proven method for discouraging pest infestations is the bio-diversity planting method. Traditionally, vegetable gardens follow the pattern of “mono-cropping” - growing a single crop. That means segregating cultivars (cultivated varieties) into rows and blocks, or filling a small plot or bed with a single crop. That practice mimics commercial production, perhaps based on the assumption that commercial growers know best. If a tomato plant is susceptible to Late Blight and it is surrounded by tomatoes, they are all vulnerable and the possibility of mass-infestation becomes a probability.

With bio-diversity a dozen or more crop varieties are placed throughout the beds including root crops, leafy greens, flowers, herbs, and fruiting crops (tomatoes and squash), beans and peas. Compared to the standard garden layout it looks like chaos but it resembles the biodiversity found in natural systems.

Choosing disease resistant plants

Planning your garden by choosing disease resistant plants is another useful EPM strategy for keeping plants healthy. Vegetable breeding research typically integrates disease resistance into their programs. Many bacterial, fungal, and viral problems can be marginalized by choosing seeds whose genetics favor the host plant over the pathogen. This method reduces infestation but doesn't eliminate diseases completely. Unfortunately, it doesn’t help suppress insect pests.

Take the time to learn how to plant many crops from seed by exploring seed catalogs. They are a source of helpful information and a great learning tool. Our favorite catalogs are High Mowing Seeds, Johnny’s Seeds, and Baker Creek Seeds.

Beneficial and predatory insects

The insect world is populated by predators and prey. We can recruit Insect predators to eliminate their prey. Ladybugs consume huge amounts of aphids. Parasitic wasps feast on cabbage loopers and tomato hornworms. The preying mantis targets grasshoppers. Some nematodes prey on slugs and snails. Parasitizers, like Trichogamma wasps, are bugs that lay eggs in their prey and when the larvae hatch, they feed on the prey. Dragonflies are a top predator with a voracious appetite that keep a healthy balance between all the insects in your yard including ornamental and native plants.

Various beneficial insect species can be purchased at garden stores and are used to control invasions of certain insects or just to achieve balance among insect populations. In some cases it will be possible to establish communities of such predators in your garden. Pollinators will be attracted by many species of flowers and aromatic herbs. Diversity of plants leads to diversity of insects.

Pest management with flowers & herbs

HERBS

• Basil – Repels thrips, flies and mosquitoes.

• Cilantro – Wards off aphids, Colorado potato beetles, and spider mites

• Chives – Repels aphids

• Dill – Can keep aphids, spider mites and squash bugs away from vegetables

• Oregano – Repels cucumber beetles and cabbage butterfly. Good understory crop that you can plant everywhere. Cut some out when you need space for a new plant.

• Mint – Plant mint in small containers and place them next to your beds. If you plant the mint in your beds they will take over!

FLOWERS

• Cosmos – Attracts good insects like bees and butterfly, also repels the corn earworm

• Marigold – The marigold is probably the most well-known plant for repelling insects. French marigolds repel whiteflies and kill bad nematodes. Mexican Marigold are the most potent for pest prevention but are not the most beautiful variety. Since garden centers will likely not stock these seedlings, grow them from seed indoors or in a “cold frame” (a raised bed protected with a glass or plastic cover).

• Nasturtium – They deter striped pumpkin beetles and other pests of the cabbage family. Nasturtiums grown near squash are said to repel squash bugs. They can be used as a trap crop for aphids.

• Sunflowers – They repel asparagus beetles, leafhoppers, a range of aphids, tomato worms, and a good many other pests.

BIRDS

Birds are often a neglected piece of this puzzle, but their impact on insect populations should not be underestimated. Install some bird feeders near the garden. Encouraging their presence will lead to more ecological balance and fewer pest issues.

The breadth of insect knowledge is encyclopedic, but you need not become an entomologist to benefit from it. Just be aware of the opportunities and take advantage of them as they present themselves. Consider installing bird houses and hummingbird feeders.

Visual inspection and manual removal

Make visual inspection your habit. It’s important to keep in mind that there is no substitute for visual inspection of the garden and physical removal of pests when possible. You may discover a huge hornworm dining on a tomato plant - you can grab it and remove it from the garden. Fungal and bacterial diseases that appear on the lower leaves of plants can be simply removed. When you’re in the garden be on the lookout for invasive activity – and act on it! Know when garden hygiene is necessary to prevent spreading of fungal and bacterial diseases by the gardener (your tools and fingers).

Control fungal diseases in humid climates. In areas like the Midwest and East Coast with humid weather and rampant fungal, viral and bacterial plant diseases that live in the soil get in the habit of regularly disinfecting tools and pots. Dip (or spray) clippers, shears and scissors in 100% alcohol before starting to remove infected leaves from a plant. Dip again each time you clip off a leaf or stem. Make sure it falls into a bag and not on the plant or soil. Spray them again when you are done. When using scissors to cut off infected leaves from tomatoes let them fall into a paper bag. Don’t use your fingers to pull them off which will just spread the disease further. Use hand sanitizer on your finger tips if you touch infected leaves. Use disposable gloves so your fingers don’t touch the alcohol.

Use dilute bleach to sterilize large tools and pots before reusing them. Here is our method: (1) Wash off soil and debris in a tub of soapy water with a small bristle brush. (2) Rinse. (3) Soak in 10% bleach for 20 minutes. (4) Let them dry. (5) Soak them in fresh clean water for a few minutes. (6) Let them dry again. Doing this easy cleaning task when necessary will save stress and time later.

Prevent flying pests from landing on crops

Physically blocking flying pests from landing on crops and laying eggs can be an effective method for protecting your plants. Remember that these physical barriers should be employed alongside other integrated pest management (IPM) strategies, such as biological control and crop rotation, to ensure long-term, sustainable pest control.

Here are some ways to achieve this:

Floating row covers: These lightweight, translucent fabrics can be draped over crops and secured at the edges, providing a physical barrier that prevents pests from reaching the plants. Row covers allow sunlight, air, and water to pass through, so they don't hinder plant growth. They are effective against cabbage moths, squash vine borer moths, and other pests like flea beetles, aphids, and leaf miners.

Insect netting: Similar to row covers, insect netting can be draped over crops or used to enclose an entire growing area. The mesh size should be small enough to prevent the target pests from passing through. Insect netting can protect various crops from pests like cabbage moths, squash vine borer moths, carrot rust flies, and whiteflies.

Greenhouses or high tunnels: Enclosing your crops in a greenhouse or high tunnel can provide a physical barrier against flying pests. Good ventilation is essential to avoid overheating and to maintain healthy plants. Greenhouses and high tunnels can protect a wide range of crops, such as tomatoes, peppers, lettuce, and cucumbers, from various flying pests, including aphids, whiteflies, and moths.

Companion planting: Some plants release chemicals that repel pests or attract beneficial insects that prey on pests. Planting these companion plants near your susceptible crops can help deter flying pests. For example, nasturtiums can repel cabbage moths, while marigolds can help repel whiteflies.

Physical traps: Sticky traps, pheromone traps, and light traps can be used to catch and reduce the population of flying pests. These traps can be effective against pests like cabbage moths, squash vine borer moths, and whiteflies.

Root and lower stem protection: Prevent the Squash Vine Borer from laying its eggs where the root and stem connect by surrounding that area with a sturdy paper cup with the bottom cut out. OR wrapping the area in aluminum foil.

Many crops can be protected this way from other flying pests:

Brassicas (cabbage, kale, broccoli, cauliflower) from cabbage moths and cabbage root maggots

Tomatoes, peppers, and eggplants from tomato hornworms and whiteflies

Lettuce and leafy greens from aphids and leaf miners

Carrots and parsnips from carrot rust flies

Cucurbits (cucumbers, melons, pumpkins) from cucumber beetles and squash bugs

Use organic pesticides as a last resort

NEEM Oil is often viewed as the be all and end all product for its insecticidal and fungicidal properties. Learn more about Neem Oil uses and drawbacks.

Bacillus thuringiensis or Bt is a naturally occurring soil bacterial parasite. There are different strains available. Learn more about  BT – timing limitations, specific insects controlled, and storage/shelf life requirements.

Pyrethrins are derived from plants and are commonly sprayed as mosquito repellants. They are fairly nonselective insect killers and highly toxic to bees.

Spinosad is derived from a bacterium and classified as an organic pesticide. Try to avoid using it because It is also toxic to bees.  

Trichoderma is a naturally occurring soil fungus that displaces gray mold. It has also shown some insecticidal impact.  It is generally used agriculturally. There's minimal information on its usefulness in the home garden. Learn more here.

Insecticidal soap is another option for insect control.  See below. Don’t use horticultural oils which are made from refined petroleum.  Learn more about Insecticidal soap.

Copper and Sulfur are considered low toxicity, effective fungicides. Fungicides can help slow the spread, but don’t  remove the problem. Use them alone with good management practices. They are often used to prevent disease.  But it's a lot of spraying. It's always a good idea to do a test application on a small area, wait 24-48 hours to see if there is any phytotoxic effect.

Our Innovative Food Gardening Method

Learn more in our two recently revised blog posts.

Our online store

See our online store for details about prices, ordering and delivery of raised beds, compost, worm castings and more. Please contact our customer support team before placing an order online so we can assist you with the details and answer your gardening questions.

QUESTIONS? COMMENTS?

Contact us at (708) 655-5299 or support[at]deep-roots-project.org.

Stay in touch

Please leave your cell phone number when you sign up for our eNewsletter, if you want text message announcements now and then.

Donations help us provide organic kitchen gardening education to individuals, organizations, and entire communities. Thank you in advance for contributing to our community and for sharing our website and blog with friends and family.

Biodiversity Helps Control Pests

Biodiversity planting methods harness the forces of nature to help protect your garden as well as individual plants from pests and disease. Think of the plant populations as a team with complimentary skills all cooperating together. Balance and a strong ecosystem are achieved for the whole community of plants.

Biodiversity: The Foundation of a Thriving Garden

Abundant productivity in a garden starts with biodiversity—the presence of many different kinds of plants, each playing its own role. Scientific research shows that diverse plant communities improve soil health, attract beneficial insects, suppress pests naturally, and make crops more resilient to stress. In simple terms: the more variety you have, the better your garden can thrive without relying on synthetic inputs.

When we grow only one type of plant in one place, the soil becomes depleted, pests take over, and diseases spread easily. But when we intentionally design for diversity—mixing vegetables, herbs, flowers, and cover crops—we create a living system where plants support one another. Some fix nitrogen, others repel pests, and many attract pollinators or break up compacted soil. This natural teamwork is the secret to healthy, high-yield gardens.

Let abundance flourish through this careful orchestration. Biodiversity isn’t just beautiful—it’s functional. When you plant a rich mix of species and rotate your crops each season, you not only grow more food, you grow healthier soil and a more self-sustaining ecosystem. Even small changes—like interplanting herbs among your vegetables or choosing three different types of tomatoes instead of one—can make a big difference.

Learn how to put biodiversity to work in your raised bed or backyard plot. Whether you’re brand new to gardening or looking to deepen your skills, biodiversity is one of the most rewarding tools you can use to build a thriving, regenerative garden.

Be creative with biodiversity

Your imagination defines the limit of biodiversity in your garden. Be a creative gardener. How do you envision your garden? Experiment with many combinations of plants. Old fashioned gardening has many rules like planting in neat rows. Biodiversity gives you the freedom to co-create with nature. A biodiverse raised bed may look like chaos compared to the traditional garden layout. But actually it resembles the biodiversity found in natural systems.

As above, so below. There are tens of thousands of microbial species living in your soil. To balance that we need to preserve plant diversity above the soil. Our diversity mimics the diversity below ground. Learn more in our recently updated blog post about soil microbes and compost.

We recommend at least a dozen different plants including veggies, herbs and flowers in each bed and the large containers surrounding the bed. It can be dominated by a single veggie like tomatoes, with a dozen smaller plants scattered around. There are many ways to do this and it's up to you the gardener to decide. Smaller plants that need sun should be on the south side of the larger plant or at least not shaded by them.

Don’t try to plan your garden alone. For most gardeners, January and February are the planning months for the new gardening season. Give yourself time to explore several possibilities. Do some reading. Explore the Deep Roots blog posts. Talk to other food gardeners. Contact our support team for some phone discussions.

Take on as much as you can handle the first year. Send us questions when you run into a problem. Gardening is all about trying new things and learning from your mistakes. Learn more about our Innovative Method in our 2 recently updated posts.

Biodiversity basics and tips

• A biodiverse food garden has a mixture of a dozen or more different plants growing throughout the bed and in surrounding containers including root crops, leafy greens, flowers, herbs, fruiting crops (tomatoes, eggplant and peppers), beans & peas and native plants.

• The mixture of plants confuses pests who seek out a good size patch of their favorite plant.

• Don’t plant the crops from the same family next to each other. A large group of the same plant has a stronger scent and attracts more pests and can more easily spread diseases.

• Two raised beds is even better than one for biodiversity planting.

• Plant large plants like tomatoes on opposite sides of your bed or in separate containers to discourage disease spread. Or, plant several tomatoes in one bed with basil and marigolds between them.

• If you plant a tomato in a big pot strategically place basil and lettuce seedlings around the base of the tomato and watch them grow together. Prune off most of the tomato’s lower foliage to allow more sun to reach the kale and basil.

• Fill empty spots with plants from a different family when you harvest a whole plant. Maximize your harvest by filling empty spots mid-season with seeds or seedlings.

• Plant seeds of small plants in several spots around the bed in small clusters (6-8” diameter) or short rows. Examples of small plants are beets, carrots, radishes, onions.

• If you want to grow a lot of the same crop like tomatoes, squash and cucumbers, figure out a way to plant them as far away from each other as possible. They can grow in their own large containers.

• Environmental Pest Management (EPM) is a method that is used in combination with Biodiversity Planting to prevent and manage pests & diseases. But biodiversity is not a complete solution for any specific pest or disease. We also use organic pesticides and fungicides in limited quantities for pest prevention.

• When you focus on a few crops because your family loves them and they are super healthy, plant lots of different flowers, herbs and small crops (lettuce, beets, radishes, strawberries, basil, marigolds, nasturtiums) at the edges of your bed and in the spaces between them.

• Don’t block the sun with large plants. Place taller plants like tomatoes at the north side of a raised bed. Place the shortest plants on the south side of the bed.

• Sunlight: Place your raised bed and large containers in the sunniest spot of your yard. 8 hours of sun or more is optimal. Some plants are okay with 5 to 8 hours of sun. They may be smaller and take longer to grow to maturity.

• Shade a cool season plant like lettuce in mid-summer next to a tall tomato plant.

• Plant small and medium size veggies that need less sun like lettuce and dill about 12” from the tomato plant’s main stem. Prune off most of the tomato’s lower foliage up to 10 inches.

• Two or three tomato plants in your raised bed is fine if you prune them properly and grow them vertically on tomato cages or trellises.

• Don’t plant huge plants like squash in your raised bed even if it grows up a trellis. Plant a huge plant in a large container next to the raised bed or in a separate bed. Place the container on the north side of your raised bed so it doesn’t block the sun. For example Butternut squash will sprawl all around the outside of the bed even if you have a trellis.

• Often, garden centers don’t have the seedlings you want mid-season. Be prepared with fresh seedlings you grow yourself by growing a few seedlings from seed in small pots filled with the half and half mixture of our microbe-rich compost and our worm castings. Make sure they get enough sun and water them daily.

• A planting calendar for your climate zone will tell you when to plant and harvest. We provide a Planting Calendar Chart for the Chicago Area since most of our gardeners are there. Ask your local state university agricultural extension for a planting calendar.

Greater plant diversity has most impact

Greater diversity of veggies, herbs & flowers has the most impact. Select plants for your bed and the surrounding containers from at least 5 of the 10 Biodiversity Plant Groups. (See list below) Ideally, select around 3 individual plants from the same plant variety to plant in one 4 x 8 raised bed. This adds up to about 10 to 15 plant small to medium-size varieties per bed and about 30 individual total plants (or clusters of tiny plants) per bed.

This list of major functional garden crop groups are not “taxonomical” classifications used by professional plant scientists. These are simplified groups organized to help you make gardening decisions. Try to plant at least five or six of these groups in each bed and you’ll achieve adequate diversity. Planting multiple cultivars within a group doesn’t contribute much to diversity. This is not a rule, rather it’s a guideline. The guideline also applies to cloth planters, on a reduced scale.

Our biodiversity plant groups

1. Legumes: peas, bush beans, pole beans

2. Herbs: (culinary & medicinal): basil, lavender, peppermint, lemon balm. sage, oregano (Used for bee attraction and repelling insects)

3. Flowers: marigold, nasturtium, calendula, echinacea, cosmos (Learn about each flower’s benefit in our post Environmental Pest Management.

4. Brassicas: cabbage, collard, kale, broccoli, cauliflower, brussel sprouts

5. Fruiting veggies: eggplant, tomato, peppers

6. Salad Greens: lettuce, spinach, swiss chard

7. Root veggies: beets, carrots, onions, scallions, garlic, radish, potato, sweet potato

8. Grain: Corn

9. Cucurbits: melons, cucumbers, squash, gourds

10. Perennials: Asparagus, artichoke (warm zones only), strawberry, bramble berries (thorny berries like blackberry and raspberry). (Blueberries are hard to grow since they need acid soil.

11. Cover crops: mustard, buckwheat, cowpeas

Our online store

See our online store for details about prices, ordering and delivery of raised beds, compost, worm castings and more. Please contact our customer support team before placing an order online so we can assist you with the details and answer your gardening questions.

QUESTIONS? COMMENTS?

Contact us at (708) 655-5299 or support[at]deep-roots-project.org.

Stay in touch

Please leave your cell phone number when you sign up for our eNewsletter, if you want text message announcements now and then.

Donations help us provide organic kitchen gardening education to individuals, organizations, and entire communities. Thank you in advance for contributing to our community and for sharing our website and blog with friends and family.

How to Sterilize Garden Tools

Garden tools play a crucial role in maintaining a healthy and beautiful garden. They help us till the soil, plant seeds, trim the plants and keep the garden in pristine condition. However, if not properly maintained and sterilized, garden tools can spread diseases and pests from one plant to another, leading to significant damage and loss. Tips for sterilizing small pre-used pots for transplanting seedlings is also highly recommended.

Sterilizing garden tools is an essential step in maintaining a healthy and beautiful garden. There are several methods that can be used to sterilize garden tools, including the use of a bleach solution, boiling water, UV-C light, heat treatment, and hydrogen peroxide. Choose the method that works best for you and your tools, and make sure to sterilize your tools regularly to keep your garden free of any harmful organisms.

Several sterilization methods available

Cleaning the tools before sterilization: Before sterilizing your garden tools, it is essential to clean them thoroughly. This will ensure that any dirt, debris, or residual plant material that may be present on the tool is removed. You can clean your tools with water, soap, and a scrub brush, or by using a solution of water and bleach (1:10 dilution).

Disinfection with a bleach solution: One of the most effective ways to sterilize garden tools is by using a bleach solution. Wear rubber gloves and don’t get the bleach on your skin. Eye protection is also beneficial.You can make a solution of 1 part bleach to 9 parts water and soak the tools in it for at least 10 minutes. This will kill any bacteria, viruses, or fungi that may be present on the tools. Make sure to rinse the tools thoroughly with water after soaking in the bleach solution to remove any residual bleach.

Sterilization with boiling water: Boiling water is another effective way to sterilize garden tools. Fill a large pot with water and bring it to a rolling boil. Carefully place the tools in the pot and let them boil for 10 to 15 minutes. This will kill any harmful organisms that may be present on the tools. After boiling, let the tools cool down before handling them.

Use of UV-C light: UV-C light is a powerful sterilization method that can be used to sterilize garden tools. UV-C light has been proven to kill 99.9% of bacteria, viruses, and fungi in a matter of minutes. You can purchase UV-C sterilization lamps, which are designed specifically for sterilizing garden tools. Simply place the tools in the lamp and let the UV-C light do its work.

Heat treatment: Heat treatment is another effective method of sterilizing garden tools. You can sterilize your tools by baking them in the oven at a temperature of 160°F for 30 minutes. This method is particularly useful for metal tools as it will kill any harmful organisms that may be present on the surface of the tool.

Use of hydrogen peroxide: Hydrogen peroxide is a powerful sterilizing agent that can be used to sterilize garden tools. Mix a solution of 3% hydrogen peroxide with water in a spray bottle, and spray it on your tools. Let the solution sit for 10 to 15 minutes and then rinse the tools with water. This method is particularly useful for sterilizing wooden handles of garden tools.

Proper tool storage

It’s worth noting that while sterilizing your tools is important, it's also crucial to properly store them to extend their life and prevent rust, wear, and other damage. Keep your tools clean, dry, and oiled to prevent rust, and store them in a cool, dry place when not in use. With proper care and maintenance, your garden tools will last for many years and help you create a beautiful and thriving garden.

“Grow Your Own Food” blog posts

See the full list of our Grow Your Own Food blog posts. Each post is assigned ”tags” which are under the post title. If you need a quick answer to a gardening question give us a call or send a text to our customer support team – support[at]deep-roots-project.org AND 708-655-5299.

Deep Roots online store

See our online store for details about prices, ordering and delivery of raised beds, planter boxes, microbe-rich compost, worm castings, leaf mulch and more. We don’t sell traditional soil, since we use 100% compost as our growing medium. Our online store has 2 sections – (1) raised beds and planter boxes and (2) compost, worm castings, fertilizer.

Please contact our customer support team before placing an order online so we can assist you with the details and answer your gardening questions. You can pay by credit card in the store or by check.

(708) 655-5299 and support[at]deep-roots-project.org

Sign up for our newsletter

Please leave your cell phone number when you sign up for our eNewsletter, if you want text message announcements now and then. 

Donations help us provide organic kitchen gardening education to individuals, organizations, and entire communities. Thank you in advance for contributing to our community and for sharing our website and blog with friends and family.

Brassica Family Pests & Diseases

The brassica family of vegetables, which includes broccolini, Brussel sprouts, cabbage, cauliflower, collards, kale, and kohlrabi, are susceptible to various pests and diseases. See our lists below of (1) common pests and diseases affecting brassicas in Northern Illinois and (2) safe organic pesticides best used to control them.

Common pests and diseases in Northern Illinois

It's important to note that while these pesticides and biofungicides are considered safe for use in organic gardening, they should still be used judiciously and according to label instructions. Overuse or misuse can harm beneficial insects and other non-target organisms. Regular monitoring and cultural practices such as crop rotation, soil testing, and good sanitation can also help prevent pest and disease problems in your brassica garden.

The swede midge fly (Contarinia nasturtii), an invasive pest from Europe, has begun wreaking havoc on brassica crops. including radish, horseradish, rutabaga, turnip, rapeseed (canola), arugula, bok choy and Chinese cabbage. Crops that are most damaged include common favorites such as broccoli, cauliflower, cabbage, kale, kohlrabi, collards and Brussels sprouts. Since we have not yet found a pesticide for swede midge our sollution is to grow only collards and kale. We harvst as soon as large leves appear throughout the sesaon. If swede midge damage appears on the base of the leaf, we cut it off and wash all harvested leaves. We have an entire post dedicated to this new pest - see Swede Midge Fly Management.

Cabbage Worms: These are small green caterpillars that chew on the leaves of cabbage, kale, and other brassicas, leaving large holes in the foliage. They can quickly defoliate the entire plant.

Aphids: These tiny, pear-shaped insects suck the sap from the leaves, stems, and buds of brassicas, causing stunted growth and distorted leaves. They also produce a sticky substance called honeydew, which can attract ants and other insects.

Flea Beetles: These small, shiny black beetles jump like fleas and feed on the leaves of brassicas, leaving tiny holes and making the plant vulnerable to other diseases.

Clubroot: This soil-borne disease is caused by a fungus that attacks the roots of brassicas, causing them to swell and become deformed. Infected plants often wilt and die.

Downy Mildew: This fungal disease causes yellowing and wilting of the leaves, along with a grayish-white mold on the undersides of the leaves. It can quickly spread from plant to plant, especially in humid conditions.

Prevent and control brassica pests and diseases

To prevent and control these pests and diseases, it's best to use a combination of cultural practices and safe organic pesticides and biofungicides. Here are some options:

Floating Row Covers: These lightweight, permeable fabrics can be placed over young brassicas to protect them from cabbage worms, flea beetles, and other pests. They can also help prevent the spread of diseases like downy mildew. See our blog post Installing Hoops on Raised Beds.

Neem Oil: This natural pesticide derived from the neem tree can be sprayed on brassicas to repel aphids and other pests. It works by disrupting the insect's hormonal balance, making it difficult for them to feed and breed.

Bt (Bacillus thuringiensis): This natural bacteria-based pesticide is effective against cabbage worms and other caterpillar pests. It works by producing a toxin that is only harmful to certain insects, leaving beneficial insects unharmed.

Copper-based Fungicides: These biofungicides can help prevent and control diseases like downy mildew and clubroot. They work by creating a protective barrier on the plant's surface that prevents the fungus from taking hold.

Beneficial Insects: Ladybugs, lacewings, and parasitic wasps are all natural enemies of aphids and other pest insects. By releasing these beneficial insects into your garden, you can help keep pest populations in check.

“Grow Your Own Food” blog posts

See the full list of our Grow Your Own Food blog posts. Each post is assigned ”tags” which are under the post title. If you need a quick answer to a gardening question give us a call or send a text to our customer support team – support[at]deep-roots-project.org AND 708-655-5299.

Deep Roots online store

See our online store for details about prices, ordering and delivery of raised beds, planter boxes, microbe-rich compost, worm castings, leaf mulch and more. We don’t sell traditional soil, since we use 100% compost as our growing medium. Our online store has 2 sections – (1) raised beds and planter boxes and (2) compost, worm castings, fertilizer.

Please contact our customer support team before placing an order online so we can assist you with the details and answer your gardening questions. You can pay by credit card in the store or by check.

(708) 655-5299 and support[at]deep-roots-project.org

Please leave your cell phone number when you sign up for our eNewsletter, if you want text message announcements now and then. 

Donations help us provide organic kitchen gardening education to individuals, organizations, and entire communities. Thank you in advance for contributing to our community and for sharing our website and blog with friends and family.