Knowing the right time to get your onions in the ground is the first step to a great harvest. If you’re wondering when to plant onions in Texas, the answer depends heavily on your specific region within the state.
Texas is a big place with varied climates, so a one-size-fits-all planting date doesn’t work. This guide will break down the optimal planting seasons for North, Central, and South Texas, helping you choose the right varieties and planting methods for success.
When to Plant Onions in Texas
Onions are a cool-season crop in Texas, grown through the fall and winter for a spring harvest. They need to be planted early enough to establish roots and tops before cold weather, but not so early that heat stunts them. The general rule is to plant onion sets, transplants, or seeds in the fall.
For most of Texas, the prime planting window is from October through December. However, this shifts earlier in the north and later in the south. Getting the timing right ensures the plants develop properly before bulbing begins in the longer, warmer days of spring.
Understanding Texas Onion Regions
Texas is broadly split into three growing regions for onions. Your location dictates your schedule more than anything else.
* North Texas: This includes areas like Dallas, Fort Worth, and Amarillo. Winters are colder with a higher risk of hard freezes. Planting should occur from mid-October to mid-November. This gives plants time to settle in before the ground freezes.
* Central Texas: This region covers Austin, Waco, and San Antonio. It has milder winters. The ideal planting time here is from early November to early December. This is often considered the most flexible window in the state.
* South Texas & the Winter Garden Area: This includes the Rio Grande Valley and areas like Laredo. Winters are very mild, and planting can be done from late November through December, even into early January in some years. The key is to avoid planting during any lingering heat.
Choosing the Right Onion Type for Texas
Not all onions grow well everywhere. Onions are classified by their day-length requirement, which is critical in Texas.
* Short-Day Onions: These begin forming bulbs when daylight lasts 10-12 hours. They are perfect for Texas, especially Central and South regions. Popular varieties include:
* Texas Supersweet (1015Y)
* Yellow Granex (Vidalia-type)
* Red Creole
* White Bermuda
* Intermediate-Day Onions: These bulb with 12-14 hours of daylight. They can work well in North and Central Texas, offering more variety options.
* Candy
* Stockton Red
* Long-Day Onions: These need 14-16 hours of daylight to bulb, common in northern states. They generally do not perform well in Texas and should be avoided.
For the best results, most Texas gardeners should stick with proven short-day varieties. The famous “1015” onion is named for its suggested planting date of October 15th in much of the state, which is a great benchmark.
How to Plant Onions Step-by-Step
Once you have your timing and variety, follow these steps for planting.
1. Select Your Planting Material. You can use seeds, sets (small bulbs), or transplants (seedlings). For fall planting in Texas, transplants are most common and reliable, giving you a head start. Sets can also work, but choose ones smaller than a dime to avoid early bolting.
2. Prepare the Soil. Onions need loose, well-draining soil with plenty of organic matter. Work the soil to a depth of about 8 inches. Mix in 2-3 inches of compost. Onions are heavy feeders, so also incorporate a balanced fertilizer or one higher in phosphorus at planting.
3. Plant Correctly. For transplants, plant them about 1 inch deep, spacing them 4 inches apart in rows that are 12-18 inches apart. Gently firm the soil around them. If using sets, press them into the soil just deep enough so the tip is level with the soil surface.
4. Water Thoroughly. After planting, give them a good, deep watering to settle the soil around the roots. Consistent moisture is key for good growth.
Caring for Your Onion Crop
Proper care through the winter and spring leads to big, healthy bulbs.
* Watering: Onions have shallow roots. Provide about 1 inch of water per week, including rainfall. Use drip irrigation or water at the soil level to keep foliage dry and prevent disease. Reduce watering as the bulbs mature and the tops begin to fall over.
* Fertilizing: Side-dress with a nitrogen fertilizer (like blood meal or a balanced garden fertilizer) every 4-6 weeks until the bulbs begin to swell. Stop fertilizing once bulbing is obvious.
* Weeding: Keep the area weed-free, as onions don’t compete well. Weed carefully by hand to avoid damaging the shallow roots.
* Mulching: Apply a 2-3 inch layer of straw or shredded leaves after planting. This conserves moisture, suppresses weeds, and moderates soil temperature through winter freezes.
Common Problems and Solutions
Even with good timing, you might face a few issues.
* Bolting: This is when an onion sends up a flower stalk too early, ruining the bulb. It’s often caused by temperature fluctuations or planting too large of a set. If you see a hard stalk form, harvest that onion and use it quickly.
* Pests: Thrips are tiny insects that cause silvery streaks on leaves. Insecticidal soap or neem oil can help control them. Onion maggots are less common but can damage roots; crop rotation is the best prevention.
* Diseases: Fungal issues like downy mildew or purple blotch can occur in wet weather. Ensure good air circulation, avoid overhead watering, and remove any infected plants promptly.
Harvesting and Storing Your Texas Onions
Your patience pays off in late spring.
* When to Harvest: Onions are ready when the tops turn yellow and begin to fall over naturally. Gently bend over any remaining tops to signal the bulbs to stop growing. A week later, carefully lift the bulbs from the soil with a fork.
* Curing: This step is crucial for storage. Lay the bulbs in a single layer in a warm, dry, well-ventilated place out of direct sun (like a garage or covered porch) for 2-3 weeks. The necks should become tight and the outer skins papery.
* Storage: After curing, trim the roots and cut the tops down to about 1 inch. Store in a cool, dry, dark place in mesh bags or a single layer. Properly cured short-day onions don’t store as long as some types, so plan to use them within a few months.
Frequently Asked Questions
What is the best month to plant onions in Texas?
For most of Texas, November is the prime month. In North Texas, lean toward late October. In South Texas, you can plant into December.
Can I plant onions in the spring in Texas?
It’s generally not recommended for bulb onions. Spring-planted onions won’t have enough time to size up before the long, hot days trigger bulbing, resulting in very small bulbs. You can plant green onions or scallions in early spring, however.
What is the famous 1015 onion?
The “1015” or Texas Supersweet onion is a legendary short-day variety developed for Texas. Its name suggests an optimal planting date of October 15th, a perfect guideline for Central Texas and a useful reference for other regions.
How long do onions take to grow in Texas?
From fall planting, onions typically take 5-6 months to reach full maturity for harvest. You can start harvesting some as green onions much earlier, though.
Why are my onions so small?
Small bulbs can result from planting the wrong day-length type, planting too late, overcrowding, insufficient fertilizer (especially nitrogen), or inconsistent watering. Make sure your variety is a short-day onion and that you planted it in the fall window.
Getting your timing right is the most important factor. By planting in the correct fall window for your region and choosing a proven short-day variety, you’ll be well on your way to a succesful harvest of sweet, homegrown onions. Remember to provide consistent care, and don’t be discouraged by a few setbacks—gardening always involves a bit of learning as you go. With this guide, you have the foundation you need to grow great onions in the Lone Star State.