North Texas gardeners can plant onions in January or February for a strong start before the summer heat arrives. Knowing exactly when to plant onions in north texas makes the difference between a bumper crop and a disappointing harvest. The timing hinges on your local frost dates and the onion variety you choose.
Onions are cool-season crops that need time to develop tops before bulbing begins. In North Texas, the window is narrow because summers arrive fast and hot. Plant too late, and your onions may bolt or produce small bulbs. Plant at the right time, and you will enjoy sweet, storage-ready onions by late spring.
When To Plant Onions In North Texas
The best time to set out onion transplants or sets is from mid-January through mid-February. Soil temperatures should be above 40°F (4°C) for roots to grow. If you start from seed, you need to begin indoors in December or early January, then transplant outdoors 4–6 weeks later.
North Texas spans USDA hardiness zones 7b to 8a, so your exact planting date may shift by a week or two. Gardeners in Dallas-Fort Worth can plant earlier than those in Wichita Falls. Check your local frost date—typically around March 15–20—and count backward 4–6 weeks for transplanting.
Understanding Day Length And Onion Types
Onions bulb based on day length. North Texas sits in a transition zone where intermediate-day onions perform best. Short-day onions also work well here. Long-day onions are not recommended because they need longer summer days than our region provides.
- Short-day onions: Start bulbing when days reach 10–12 hours. Plant in January for harvest in May. Examples: Texas SuperSweet, Red Creole, White Bermuda.
- Intermediate-day onions: Start bulbing at 12–14 hours. These are ideal for North Texas. Examples: Candy, Red Candy Apple, SuperStar.
- Long-day onions: Require 14–16 hours. Not suitable for our area unless you live far north of Dallas.
Soil Preparation For Onions
Onions need loose, well-draining soil with a pH between 6.0 and 7.0. Heavy clay soil in North Texas can cause rot. Amend your bed with compost or aged manure a few weeks before planting. Raised beds work great for drainage.
- Test your soil pH with a simple kit from a garden center.
- Add lime if pH is below 6.0; add sulfur if above 7.0.
- Mix in 2–3 inches of organic matter.
- Remove rocks and break up clumps.
- Rake the bed smooth before planting.
Planting Onion Sets Vs Transplants Vs Seeds
Most North Texas gardeners use onion sets (small bulbs) or transplants (young plants). Sets are easier but offer fewer variety choices. Transplants give you more control over timing and variety. Seeds require more work but are cheapest.
Onion Sets
Plant sets 1 inch deep and 4–6 inches apart. Space rows 12–18 inches apart. Press them into the soil so the tip is just below the surface. Water well after planting.
Transplants
Set transplants 1 inch deep, spacing them 4–6 inches apart. Trim the tops to 4 inches tall to reduce transplant shock. Water immediately and keep soil moist for the first week.
Seeds
Start seeds indoors 8–10 weeks before your transplant date. Sow ¼ inch deep in seed-starting mix. Keep under grow lights or in a sunny window. Harden off plants for a week before moving them outside.
Step-By-Step Planting Guide For North Texas
Follow these steps to plant onions at the right time in North Texas. Each step builds on the last to give your onions the best chance.
- Choose your onion variety. Pick short-day or intermediate-day types. Avoid long-day onions.
- Prepare your soil. Amend with compost and check drainage. Onions hate wet feet.
- Wait for the right temperature. Soil should be workable, not frozen or muddy. Aim for mid-January to mid-February.
- Plant at the correct depth. Sets and transplants go 1 inch deep. Seeds go ¼ inch deep.
- Space properly. 4–6 inches apart for bulbs. Closer spacing for green onions.
- Water thoroughly. Give 1 inch of water per week if rain is scarce.
- Mulch lightly. Use straw or shredded leaves to keep soil cool and moist.
Frost Protection For Early Plantings
January and February in North Texas can bring surprise freezes. Onions can handle light frosts, but hard freezes below 28°F may damage tops. Cover young plants with row cover or old sheets if a freeze is forecast.
Do not use plastic directly on plants—it traps moisture and causes rot. Remove covers during the day if temperatures rise above freezing. Hardy onion varieties like Texas SuperSweet can survive brief cold snaps without protection.
Watering And Fertilizing Schedule
Onions need consistent moisture, especially during bulb formation. Too little water makes small, hot bulbs. Too much water causes rot. Aim for 1 inch of water per week from rain or irrigation.
Fertilize every 2–3 weeks with a balanced fertilizer like 10-10-10. Stop fertilizing once bulbs start to swell—usually in April. High nitrogen after bulbing can cause thick necks that rot in storage.
- Week 1–4: Water 2–3 times per week if no rain.
- Week 5–8: Reduce to once per week as roots establish.
- Week 9–12: Maintain 1 inch per week during bulbing.
- After bulbing: Stop watering to allow skins to dry.
Common Mistakes When Planting Onions In North Texas
Even experienced gardeners make errors with onion timing. Here are the most frequent problems and how to avoid them.
Planting Too Late
If you plant in March or April, your onions may not have enough cool weather to grow tops. Then summer heat triggers early bulbing, resulting in small bulbs. Stick to the January–February window.
Planting Too Deep
Onions planted too deep struggle to form bulbs. The bulb needs to sit at or just below the soil surface. If you bury the whole set, the stem may rot.
Overcrowding
Close spacing forces onions to compete for nutrients and water. You end up with many small bulbs instead of a few large ones. Give each plant 4–6 inches of space.
Ignoring Soil PH
North Texas soil is often alkaline. Onions prefer slightly acidic to neutral soil. Test and amend if needed. Yellowing leaves may indicate a pH problem.
Harvesting And Storing Onions In North Texas
Onions are ready to harvest when the tops fall over and turn brown. This usually happens in late May or early June for January-planted onions. Do not wait too long—rainy weather can cause rot.
- Stop watering once tops fall over.
- Wait 2 weeks, then gently lift bulbs with a garden fork.
- Brush off soil, do not wash.
- Cure in a warm, dry, shaded spot for 2–3 weeks.
- Cut off tops and store in a cool, dark place.
Best Onion Varieties For North Texas
Choose varieties proven to perform in our climate. Here are top picks from local extension services and experienced gardeners.
- Texas SuperSweet: Short-day, very sweet, stores well for 3–4 months.
- Candy: Intermediate-day, large bulbs, mild flavor.
- Red Creole: Short-day, red skin, good for fresh eating.
- White Bermuda: Short-day, white flesh, early harvest.
- Red Candy Apple: Intermediate-day, deep red, stores well.
Frequently Asked Questions About Onion Planting In North Texas
Can I Plant Onions In The Fall In North Texas?
Yes, you can plant onion sets in October for a spring harvest. However, winter freezes may damage young plants. Many gardeners prefer January planting for more reliable results.
What Happens If I Plant Onions Too Early In North Texas?
If you plant in December, a hard freeze can kill the tops. Onions may survive but will be stunted. Wait until soil temperatures are consistently above 40°F.
How Deep Should I Plant Onion Sets In North Texas Soil?
Plant sets 1 inch deep with the tip just below the surface. In heavy clay, plant slightly shallower to prevent rot. In sandy soil, you can go a bit deeper.
Do Onions Need Full Sun In North Texas?
Yes, onions need at least 6–8 hours of direct sunlight daily. Less sun results in thin tops and small bulbs. Choose a sunny spot in your garden.
Can I Grow Onions From Kitchen Scraps In North Texas?
You can regrow green onions from the root ends in water, but they won’t form large bulbs. For bulb onions, use sets, transplants, or seeds from a reliable source.
Final Tips For Success With Onions In North Texas
Planting onions at the right time is the most important step. Mark your calendar for mid-January and prepare your bed in December. Keep an eye on the weather and protect young plants from hard freezes.
Onions are forgiving if you give them proper spacing, water, and sunlight. Do not skip soil preparation—it pays off at harvest. With the right timing, you will have sweet, homegrown onions by late spring.
Remember that each season is slightly different. A warm January lets you plant early. A cold February may delay planting by a week. Watch your local forecast and adjust accordingly. Your onions will thank you.