Mississippi’s warm climate lets you plant onions in both fall and early spring for two harvests. Finding the best time to plant onions in mississippi depends on your region and the onion variety you choose. This guide breaks down everything you need to know for a successful crop.
Understanding Mississippi’s Growing Zones
Mississippi spans USDA hardiness zones 7a through 9a. The northern part of the state is cooler, while the southern coastal area stays warmer longer. This affects when you should plant.
Onions are cool-season crops. They need a period of cool weather to develop roots and tops before bulbing begins. In Mississippi, you have two main planting windows: fall and early spring.
Fall Planting For Spring Harvest
Fall planting is the most popular method in Mississippi. It gives onions a head start. You plant sets or transplants in late September to early November, depending on your location.
- Northern Mississippi: Plant from mid-September to mid-October.
- Central Mississippi: Plant from late September to late October.
- Southern Mississippi: Plant from early October to mid-November.
The goal is to get onions established before the first hard frost. They will grow slowly through winter and then take off in early spring. Harvest comes in late May or June.
Spring Planting For Summer Harvest
If you miss the fall window, you can plant in early spring. This is the second best time to plant onions in Mississippi. Plant as soon as the soil is workable, usually February to March.
- Northern Mississippi: Plant from late February to late March.
- Central Mississippi: Plant from mid-February to mid-March.
- Southern Mississippi: Plant from early February to early March.
Spring-planted onions will mature in mid to late summer. They may not get as large as fall-planted ones, but they still produce a good harvest.
Best Time To Plant Onions In Mississippi
The absolute Best Time To Plant Onions In Mississippi is in the fall, specifically from mid-October to early November for most of the state. This timing allows the onions to establish roots during the mild winter and then grow rapidly in spring.
Why fall? Onions need a certain number of daylight hours to form bulbs. By planting in fall, they get the cool temperatures needed for root growth and then respond to lengthening days in spring. Spring-planted onions have less time to develop before the heat of summer triggers bulbing.
Choosing The Right Onion Variety
Not all onions are created equal. In Mississippi, you need short-day or intermediate-day varieties. Long-day onions won’t bulb properly here because the days aren’t long enough.
Short-day onions are best for fall planting. They start bulbing when days reach 10-12 hours. Good choices include:
- Texas SuperSweet
- Granex (Vidalia type)
- Red Creole
- White Bermuda
Intermediate-day onions work for both fall and spring planting. They bulb when days reach 12-14 hours. Try:
- Candy
- Red Candy Apple
- SuperStar
Avoid long-day varieties like Walla Walla or Yellow Sweet Spanish. They need 14-16 hours of daylight and will only grow tops in Mississippi.
Soil Preparation For Onions
Onions need loose, well-drained soil with plenty of organic matter. Prepare your bed a few weeks before planting.
- Choose a sunny spot. Onions need full sun, at least 6 hours daily.
- Remove weeds and rocks. Onions don’t compete well.
- Loosen soil to 8-10 inches deep.
- Mix in 2-4 inches of compost or aged manure.
- Add a balanced fertilizer like 10-10-10 at a rate of 1 pound per 100 square feet.
- Rake the bed smooth.
Soil pH should be between 6.0 and 7.0. Test your soil and adjust with lime if needed.
Planting Onion Sets Or Transplants
You can start from seeds, but sets (small bulbs) or transplants are easier and faster. Here’s how to plant them.
Planting Sets
- Push sets into the soil so the tip is just above the surface.
- Space sets 4-6 inches apart in rows 12-18 inches apart.
- Water well after planting.
Planting Transplants
- Dig a small hole deep enough to cover the roots.
- Place the transplant so the base of the green stem is just below soil level.
- Space transplants 4-6 inches apart.
- Firm soil around them and water.
If planting in fall, mulch with straw or leaves to protect from frost. Remove mulch in early spring.
Watering And Fertilizing
Onions need consistent moisture, especially during bulbing. Water deeply once a week if there’s no rain. Don’t let soil dry out completely.
Fertilize every 2-3 weeks with a nitrogen-rich fertilizer. Use blood meal, fish emulsion, or a balanced fertilizer like 20-20-20. Stop fertilizing once the bulbs start to swell.
Overwatering can cause rot. Make sure soil drains well. Raised beds help in heavy clay soil.
Weed Control
Onions have shallow roots and don’t compete with weeds. Keep the bed weed-free. Hand pull weeds carefully to avoid disturbing onion roots.
Mulch with straw or grass clippings to suppress weeds and retain moisture. Apply a 2-3 inch layer after planting.
Pest And Disease Management
Common onion pests in Mississippi include thrips, onion maggots, and cutworms. Diseases like downy mildew and pink root can also be problems.
- Use row covers to protect young plants from insects.
- Rotate crops. Don’t plant onions in the same spot for 3-4 years.
- Remove infected plants immediately.
- Apply neem oil or insecticidal soap for thrips.
Healthy plants resist pests better. Good soil, proper spacing, and adequate water help.
Harvesting Onions
Onions are ready when the tops fall over and turn brown. This happens in late spring for fall-planted onions and mid-summer for spring-planted ones.
- Stop watering once tops fall over.
- Wait a few days, then pull onions on a dry day.
- Lay them in a single layer in a shaded, well-ventilated area.
- Let them cure for 2-3 weeks until the necks are dry.
- Cut off tops and roots, then store in a cool, dry place.
Don’t wash onions before storing. Brush off loose soil instead.
Common Mistakes To Avoid
Many gardeners make these errors. Avoid them for better results.
- Planting too deep. Onions need the top of the bulb exposed.
- Overcrowding. Give each onion room to grow.
- Planting long-day varieties. They won’t bulb.
- Ignoring soil pH. Onions need slightly acidic soil.
- Watering inconsistently. This causes small or misshapen bulbs.
Learn from these mistakes and your onion crop will improve.
Regional Tips For Mississippi
Mississippi’s climate varies. Here are specific tips for different areas.
Northern Mississippi (Zones 7a-7b)
Fall planting is best from mid-September to mid-October. Spring planting can start in late February. Protect fall-planted onions with mulch during cold snaps. Choose short-day varieties like Texas SuperSweet.
Central Mississippi (Zones 8a-8b)
Plant fall onions from late September to late October. Spring planting is from mid-February to mid-March. Both short-day and intermediate-day varieties work well. Watch for thrips in late spring.
Southern Mississippi (Zones 8b-9a)
Fall planting can extend to mid-November. Spring planting starts in early February. The warmer climate means onions mature faster. Use short-day varieties for best results. Water more frequently in dry spells.
Onion Companion Plants
Planting onions near certain crops helps both. Good companions include:
- Carrots (onions repel carrot fly)
- Beets
- Lettuce
- Strawberries
- Tomatoes (onions deter aphids)
Avoid planting onions near beans, peas, or asparagus. They compete for nutrients.
Storing Onions For Long Use
Proper storage extends your harvest. Follow these steps.
- Store in a cool, dark place with good air circulation.
- Ideal temperature is 40-50°F.
- Keep humidity low to prevent sprouting.
- Don’t store onions with potatoes. Potatoes release moisture that spoils onions.
- Check regularly and remove any that are soft or sprouting.
Sweet onions like Vidalia don’t store as long as pungent varieties. Use them first.
Frequently Asked Questions
Can I plant onions in Mississippi in the summer?
No, summer is too hot. Onions need cool weather for root growth. Plant in fall or early spring only.
What is the best onion to grow in Mississippi?
Short-day varieties like Texas SuperSweet, Granex, and Red Creole perform best. They are adapted to the region’s day length.
How deep should I plant onion sets?
Plant sets so the tip is just above the soil surface. About 1 inch deep is ideal. Deeper planting can cause rot.
Do onions need full sun in Mississippi?
Yes, full sun is essential. Onions need at least 6 hours of direct sunlight daily to form large bulbs.
Can I grow onions from seed in Mississippi?
Yes, but it takes longer. Start seeds indoors 8-10 weeks before your planting date. Transplants are easier for beginners.
Why are my onions not bulbing?
Several reasons: wrong variety for your day length, planted too late, or too much nitrogen. Ensure you use short-day or intermediate-day onions and stop fertilizing when bulbing starts.
Final Thoughts On Planting Onions In Mississippi
Timing is everything for onions. The best time to plant onions in Mississippi is fall, but spring planting works too. Choose the right variety, prepare your soil, and give them consistent care. You’ll enjoy fresh, homegrown onions from your garden.
Remember to adjust planting dates based on your specific location within the state. Northern gardeners plant earlier in fall and later in spring than southern gardeners. With a little planning, you can harvest onions twice a year.
Start with a small patch and expand as you gain experience. Onions are rewarding and easy to grow once you understand their needs. Happy planting.