Root Crops Planting Calendar
Planting & Setup
Root crops grow underground and require a different soil environment than most other vegetables. This group includes carrots, beets, radishes, potatoes, turnips, and parsnips. They develop best in loose, mineral sandy topsoil with low nitrogen levels. Since root veggies don’t like high nutrient soil, too much compost can lead to poor root development, even when plants look healthy above ground. In the Deep Roots system, root crops are grown in dedicated mineral soil beds with PhoSul fertilizer to support proper root formation with phosphorus. Note - Alliums (onions, garlic, and leeks) are not root veggies and like higher nutrient soil.
| Crop Name | How To Plant | Spring Planting | Fall Planting | Germinate Indoors |
|---|---|---|---|---|
| Beets | Direct Seed | 3/25–5/15 | 8/1–9/15 | No |
| Carrots | Direct Seed | 3/20–5/15 | 8/1–9/15 | No |
| Parsnips | Direct Seed | 3/20–5/1 | None | No |
| Radishes | Direct Seed | 3/15–5/30 | 8/15–10/1 | No |
| Turnips | Direct Seed | 3/25–5/30 | 8/1–9/15 | No |
| Rutabagas | Direct Seed | 4/1–5/30 | 7/15–8/15 | No |
| Potatoes | Seed Pieces | 4/1–5/15 | None | No |
| Sweet Potatoes | Slips | 5/20–6/20 | None | Optional |
Growing Conditions
| Crop Name | Sunlight | Temperature Tolerances | Ideal Soil Temperature | Seed Depth | Days to Harvest |
|---|---|---|---|---|---|
| Beets | Full–part | 25°F–85°F | 60–75°F | 0.5 in. | 50–70 |
| Carrots | Full–part | 25°F–80°F | 60–70°F | 0.25 in. | 60–80 |
| Parsnips | Full sun | 20°F–75°F | 55–70°F | 0.5 in. | 90–120 |
| Radishes | Full–part | 25°F–85°F | 60–75°F | 0.25 in. | 25–40 |
| Turnips | Full–part | 20°F–85°F | 60–75°F | 0.5 in. | 40–60 |
| Rutabagas | Full sun | 20°F–75°F | 60–70°F | 0.5 in. | 80–100 |
| Potatoes | Full sun | 40°F–85°F | 60–70°F | 4 in. | 80–110 |
| Sweet Potatoes | Full sun | 55°F–95°F | 70–85°F | 4 in. | 90–120 |
Root crops play by different rules. Instead of trying to grow fast above ground, they want to store energy underground. They only do that when the soil sends the right signal: nutrients are present, but not excessive. In rich compost-based soil, especially manure compost, nitrogen levels are often too high. The plant responds by putting energy into leaves instead of roots, which is why gardeners sometimes get beautiful tops but small, disappointing roots.
Beets: Thin early for baby beets and harvest the rest when full size. Beets love sheep manure fertilizer.
Carrots: Over winter in the bed to optimize sweetness. Very tiny seeds are tricky to plant. Keep seeds and new sprouts moist constantly. Great tips in video How to sow carrot seeds that includes protecting seeds with a board or a layer of vermiculite until they germinate. To harvest carrots find one whose top is sticking out of the soil. If it pulls out easily it is ready to harvest. They will not be ready all at the same time.
Parsnip: Over-winter in the bed to optimize sweetness.
Radish: Fastest crop to grow to maturity.
Sweet potatoes need different soil than the other root veggies – one part compost to 2 parts topsoil. They are not planted with seeds. Instead plant “slips” which are seedlings grown on a sweet potato sitting in water – not in soil. In Zone 6a, plant sweet potato slips outdoors in late May to early June, generally 3–4 weeks after the last spring frost once the soil has warmed to at least 65º F and nights are consistently above 55º F. Slips are extremely tender, so they should not be planted until all danger of frost has passed. Video Grow Sweet Potato Slips blog post.
Alliums are root bulb veggies like garlic, onions and leeks are NOT true root veggies, They have different growing requirements like higher nutrient soil. Check our blog post on Garlic, Onions & Alliums.
