If you’re wondering when to plant onions in Mississippi, you’ve come to the right place. Getting the timing right is the single most important step for a succesful harvest, and this guide will cover the best planting times for your garden.
Mississippi’s long, warm growing season is perfect for onions, but they need a cool start. Planting at the correct moment ensures your bulbs have enough time to grow large and sweet before the summer heat arrives. Let’s break down the calendar so you can plan with confidence.
When to Plant Onions in Mississippi – Best Planting Times for
For most of Mississippi, the prime planting window is in the fall or very early spring. Onions are a cool-season crop, and they thrive when they can establish roots and foliage during the cooler months.
Fall Planting (Recommended for Southern MS)
In the southern half of the state (Zones 8b and 9a), fall planting is often the best strategy. You’ll plant onion sets or transplants, not seeds, in October through early December.
- This gives the plants a head start on root growth over the mild winter.
- Come spring, they jump into leaf production much earlier.
- The result is often larger, earlier-maturing bulbs.
Spring Planting (Statewide Option)
For all regions, spring planting is a reliable method. The target is to get onions in the ground as soon as the soil is workable—not soggy, but not frozen.
- North Mississippi (Zone 7b): Plant from mid-January through February.
- Central Mississippi (Zone 8a): Plant from late January through mid-February.
- South Mississippi (Zones 8b-9a): Plant from January through early February.
Missing this window and planting to late in spring is a common mistake. It leads to small bulbs because the plant doesn’t have enough time to grow before summer triggers bulbing.
Understanding Onion Types: Day Length is Key
Before you plant, you must choose the right type of onion for our latitude. Onions are classified by the ammount of daylight they need to form a bulb.
- Short-Day Onions: These bulb up once daylight reaches 10-12 hours. They are perfect for Mississippi’s southern latitudes. Popular varieties include Texas Sweet, Grano, and Red Burgundy.
- Intermediate-Day Onions: These need 12-14 hours of daylight. They are versatile and grow well througout most of the state. Try Candy, Super Star, or Cabernet.
Avoid long-day onions, as they won’t recieve enough daylight in Mississippi to form proper bulbs.
Step-by-Step Planting Guide
Follow these steps to get your onions off to a strong start.
1. Prepare Your Soil
Onions need loose, well-draining soil with plenty of organic matter. A week or two before planting, work your garden bed.
- Add 2-3 inches of compost or aged manure.
- Mix in a balanced, slow-release fertilizer according to package directions.
- Ensure the planting area gets full sun—at least 6-8 hours daily.
2. Choose Your Planting Material
You have three options, each with its own pros.
- Sets: Small, dormant bulbs. Easiest to plant, but can bolt (flower) more easily. Best for spring planting.
- Transplants: Small, live onion plants sold in bunches. Excellent for both fall and spring planting. They offer a wide variety selection.
- Seeds: Most economical, but require starting indoors 8-10 weeks before your outdoor planting date. Gives the most control over variety.
3. Planting Day
- Create shallow rows about 1 inch deep.
- Space sets or transplants 4-6 inches apart within the row.
- Space rows 12-18 inches apart to allow for weeding and growth.
- Place them in the soil so the tip (for sets) or the white base (for transplants) is just barely covered. Don’t bury them to deep.
- Water gently but thoroughly to settle the soil around the roots.
Caring for Your Onion Crop
Consistent care is simple but crucial for plump bulbs.
Watering & Weeding
Onions have shallow roots and need consistent moisture, especially during bulb formation. Water when the top inch of soil feels dry. A layer of mulch helps retain moisture and suppress weeds, which compete heavily with onions for nutrients.
Fertilizing
Feed your onions every 2-3 weeks with a nitrogen-rich fertilizer until the bulbs begin to swell. Once you see the soil start to crack around the forming bulb, switch to a low-nitrogen, high-phosphorus fertilizer to support bulb development.
Pest and Disease Watch
Onions have few problems, but stay vigilant.
- Thrips: Tiny insects that cause silvery streaks. Control with insecticidal soap.
- Onion Maggots: Use row covers in spring to prevent flies from laying eggs.
- Ensure good air circulation and avoid overhead watering to prevent fungal diseases like downy mildew.
Harvesting and Curing Your Bounty
Harvest time typically comes in late spring or early summer. Watch for the signal: when about half the tops have fallen over naturally, it’s time.
- Gently loosen the soil and lift the bulbs on a sunny, dry day.
- Lay them in a single layer in a warm, dry, airy place out of direct sun for 1-2 weeks. A covered porch or well-ventilated shed is ideal.
- Once the necks are tight and the outer skins are papery, trim the roots and cut the tops down to 1 inch.
- Store your cured onions in a cool, dry, dark place in a mesh bag or single layer.
Frequently Asked Questions (FAQ)
What is the best month to plant onions in Mississippi?
For spring planting, January to February is ideal. For fall planting in southern areas, aim for October to November.
Can you plant onions in the fall in Mississippi?
Yes, absolutely. Fall planting is highly recommended for the southern coastal counties and can lead to an earlier and often larger harvest.
How late is to late to plant onions?
If you’re planting in spring, getting them in by mid-March at the very latest is crucial for North and Central MS. Later planting risks the bulbs not maturing before intense summer heat.
Do onions need full sun?
Yes, they require a minimum of 6-8 hours of direct sunlight per day to produce good-sized bulbs. More sun is generally better.
Should I use onion sets or plants?
Beginners often find sets easiest. For the best variety selection and to avoid bolting, many experienced gardeners prefer transplants or seeds started indoors.
With the right timing and these simple steps, you’ll be well on your way to a fantastic onion harvest. Remember, the effort you put in during the cool season is what fills your pantry with sweet, homegrown flavor for months to come.