Turnips need six to eight weeks of cool weather before the first hard frost, so count backward from that date to find your planting window. If you are wondering when do you plant turnips in the fall, the short answer is late summer to early autumn, depending on your growing zone. The goal is to let them mature in crisp, cool air, which gives them a sweeter, milder flavor than spring-planted turnips.
Getting the timing right is not difficult, but it does require a little planning. You want the soil to be warm enough for germination, yet the air to be cool enough for the roots to develop properly. Let’s break down the exact steps so you can harvest a solid crop before winter truly sets in.
Why Fall Planting Works So Well
Turnips are a cool-season crop. They actually prefer temperatures between 50°F and 65°F. When you plant them in late summer, the seedlings emerge in warm soil, but the maturing roots experience cooler nights. This temperature shift triggers the plant to convert starches into sugars. That is why a fall turnip tastes noticeably sweeter than one grown in the spring.
Another benefit is pest pressure. Many root maggots and flea beetles are less active in the fall. You will likely deal with fewer insect problems, which means cleaner roots and less hassle for you.
When Do You Plant Turnips In The Fall
This is the core question, and the answer hinges on your local first frost date. You need to find the average date of the first hard frost in your area. A hard frost is typically 28°F or lower. Once you have that date, count backward 60 to 70 days. That is your ideal seeding window.
For most gardeners, this falls between mid-July and early September. However, you can be more precise by looking at the days-to-maturity on your seed packet. If you are growing a quick variety like “Tokyo Cross” (35 days), you can plant later. If you are growing a storage type like “Purple Top White Globe” (55 days), you need to plant earlier.
How To Calculate Your Exact Date
Here is a simple three-step process to nail the timing every year.
- Look up your average first frost date. Use a local extension office or an online frost date calculator.
- Check your seed packet for the “days to maturity” number.
- Add 10 to 14 days to that number. This accounts for slower growth in the shortening daylight of fall.
Subtract that total from your frost date. The result is your planting date. For example, if your frost date is October 15 and your turnips need 50 days, you should plant around August 20. This gives you a buffer for slower growth.
Zone By Zone Breakdown
Here is a rough guide for different USDA hardiness zones. This is not exact, but it gives you a starting point.
- Zone 2-3: Plant in early to mid-July. Your growing season is short, so use fast-maturing varieties.
- Zone 4-5: Plant in late July to early August. You have a good window for standard varieties.
- Zone 6-7: Plant in mid-August to early September. This is the sweet spot for most gardeners.
- Zone 8-9: Plant in September or even October. You can often grow turnips all winter in mild climates.
If you live in a warmer zone, you can also plant a second succession crop three weeks after the first. This gives you a continuous harvest rather than a single glut of roots.
Soil Preparation For Fall Turnips
Turnips are not heavy feeders, but they do demand loose, well-draining soil. If your soil is compacted or full of rocks, the roots will fork or become stunted. You need to prepare the bed before you sow the seeds.
Start by removing any old summer crops or weeds. Then, loosen the soil to a depth of at least 8 inches. Turnips do not like fresh manure, so avoid adding it right before planting. Instead, work in a little compost or a balanced fertilizer like 10-10-10. Keep the soil light and fluffy.
Testing Your Soil Ph
Turnips prefer a soil pH between 6.0 and 7.5. If your soil is too acidic, the roots may not develop well. A simple soil test kit from a garden center will tell you where you stand. If the pH is low, add some lime a few weeks before planting. If it is too high, add sulfur.
Do not overthink this step. Most garden soils are fine for turnips. Just make sure the bed is not waterlogged. Turnips will rot in soggy conditions, especially in the cooler, wetter fall weather.
How To Sow Turnip Seeds
Turnips are direct-seeded. They do not transplant well because their taproot is sensitive to disturbance. You will sow the seeds straight into the garden bed.
Here is the step-by-step process for perfect seeding.
- Rake the soil surface smooth and remove any clumps.
- Make a shallow furrow about 1/2 inch deep. You can use a stick or the edge of a hoe.
- Sow the seeds thinly along the row. Aim for about 1 seed per inch.
- Cover the seeds with soil and gently firm it down.
- Water the row thoroughly with a gentle spray. Keep the soil moist until seedlings appear.
Seeds usually germinate in 7 to 14 days. If the soil is warm, they will sprout faster. If the weather is hot and dry, you may need to water more frequently. Do not let the soil dry out completely during germination, or the seeds will fail.
Spacing And Thinning
Once your seedlings are about 2 inches tall, you need to thin them. This is critical. If you leave them crowded, you will get tiny, misshapen roots. Thin the plants to about 4 inches apart for standard turnips. If you are growing smaller salad turnips, you can space them 2 inches apart.
Do not throw away the thinnings. You can wash them and add them to a salad. The young greens are spicy and delicious. Thinning also improves air circulation, which reduces the risk of fungal diseases.
Watering And Mulching
Consistent moisture is the secret to tender turnips. If the soil dries out and then gets wet again, the roots can crack or become woody. You want to keep the soil evenly moist, not soaking wet.
Water deeply once a week if there is no rain. In the fall, evaporation is slower, so you may not need to water as often. Check the soil by sticking your finger an inch into the ground. If it feels dry, it is time to water.
Adding a layer of organic mulch, like straw or shredded leaves, helps retain moisture. It also keeps the soil temperature more stable. This is especially useful if you have a warm spell in September that could stress the plants.
Fertilizing For Root Growth
Turnips need nitrogen for leafy growth, but too much nitrogen will give you big tops and small roots. You want a balanced approach. If you prepared the soil with compost, you likely do not need extra fertilizer.
However, if your soil is poor, you can side-dress the plants with a low-nitrogen fertilizer about three weeks after emergence. Use something like 5-10-10. This encourages root development without excessive foliage.
Do not fertilize late in the season. This can cause the roots to split. Once the turnips are close to maturity, just let them be.
Pest And Disease Management
Fall turnips have fewer pests, but you still need to watch for a few common issues. Flea beetles can pounce on young leaves, leaving small holes. You can protect the seedlings with a floating row cover. This is a lightweight fabric that lets in light and water but keeps insects out.
Aphids can also appear on the undersides of leaves. A strong blast of water from the hose will knock them off. If the infestation is severe, use an insecticidal soap.
Root maggots are the most damaging pest. They tunnel into the roots and ruin them. To prevent this, rotate your crops. Do not plant turnips in the same spot where you grew other brassicas (like cabbage or broccoli) the previous year.
Common Diseases
Club root is a fungal disease that causes swollen, distorted roots. It thrives in acidic, wet soil. You can avoid it by maintaining a pH above 6.5 and ensuring good drainage. If you have had club root before, you may need to wait several years before planting brassicas in that bed again.
Downy mildew appears as yellow patches on the leaves. It happens in cool, humid weather. Space your plants properly and water at the base of the plant, not overhead. This keeps the foliage dry.
Harvesting Your Fall Turnips
You can start harvesting turnips as soon as they are large enough to eat. Baby turnips, about 1 to 2 inches in diameter, are the most tender and sweet. You do not have to wait for them to reach full size.
If you want larger storage turnips, wait until they are 3 to 4 inches across. Do not let them get too big, or they will become tough and woody. The flavor declines as they size up.
To harvest, loosen the soil with a garden fork and gently pull the roots out. Do not yank them by the leaves, or the tops will break off. Brush off the excess soil, but do not wash them until you are ready to eat them. Washing removes the protective outer layer and shortens their storage life.
Storing Turnips For Winter
Fall turnips can last for months if stored correctly. Cut off the greens, leaving about an inch of stem. The greens will pull moisture from the roots if left attached. Place the roots in a perforated plastic bag in the refrigerator. They will keep for several weeks.
For longer storage, keep them in a cool, dark place like a root cellar. The ideal temperature is 32°F to 40°F with high humidity. You can also bury them in a bucket of damp sand. This prevents them from drying out.
Do not store turnips near apples or pears. These fruits release ethylene gas, which can cause the turnips to become bitter.
What To Do With Turnip Greens
Do not discard the greens. They are highly nutritious and taste similar to mustard greens. You can harvest a few leaves from each plant while the roots are still growing. Just do not take more than a third of the leaves, or the root growth will slow down.
Young, tender greens are great in salads. Larger leaves are better cooked. You can sauté them with garlic and olive oil, or add them to soups and stews. They cook down significantly, so use a lot.
Frequently Asked Questions
Can I Plant Turnips In October?
Yes, if you live in a mild climate (zones 8-9) or if you are using a very fast-maturing variety. In cooler zones, October planting is too late because the ground will freeze before the roots mature. You need at least 40 days of growing time.
How Late Can I Plant Turnips Before Frost?
You should plant at least 6 to 8 weeks before the first expected frost. If you plant too late, the roots will not have time to size up. However, mature turnips can survive light frosts. In fact, a light frost improves their flavor.
Do Turnips Need Full Sun In The Fall?
Turnips prefer full sun, which is at least 6 hours of direct sunlight per day. However, in warmer climates, they appreciate some afternoon shade. The cooler fall sun is usually not too intense, so full sun is fine.
Can I Plant Turnips After A Summer Crop?
Absolutely. This is a great way to maximize your garden space. You can plant turnips after you harvest early beans, peas, or lettuce. Just make sure to clear the debris and add a little compost before sowing the turnip seeds.
Why Are My Fall Turnips All Leaves And No Root?
This usually happens when there is too much nitrogen in the soil. It can also happen if the plants are too crowded or if the weather is too warm. Make sure you thin the seedlings and avoid high-nitrogen fertilizers. The roots will develop when the weather cools down.
Final Tips For Success
Growing fall turnips is a rewarding way to extend your harvest season. The key is to not wait too long. Mark your calendar with your frost date and count backward. Write down the date you plan to sow the seeds.
Keep a garden journal. Note what worked and what did not. If you planted too early and the roots were tough, adjust your date next year. If you planted too late and got small roots, move the date up a week.
Turnips are forgiving. Even if you miss the perfect window, you will likely get a decent crop. The cool fall weather does most of the work for you. Just give them consistent water, loose soil, and enough time to mature.
So, when do you plant turnips in the fall? The answer is simple: count back 60 to 70 days from your first frost, and get those seeds in the ground. Your future self will thank you when you are enjoying sweet, homegrown roots in November.