Growing onions in Florida means choosing short-day varieties that bulb when daylight hours are limited. If you are wondering how to grow onions in Florida, you need to start with the right timing and the correct onion type. Florida’s mild winters and hot summers create a unique growing window that is different from northern states. This guide walks you through every step, from selecting seeds to harvesting sweet, homegrown bulbs.
Onions are a staple in many kitchens, and growing them in your Florida garden is surprisingly easy once you understand the climate. The key is to plant in the fall or early winter so the onions mature before the heat arrives. Let’s break down the entire process so you can enjoy a successful harvest.
How To Grow Onions In Florida
To get started, you need to know that Florida gardeners must use short-day onion varieties. These onions start forming bulbs when daylight reaches 10 to 12 hours, which happens naturally during Florida’s shorter winter days. Long-day or intermediate varieties will not bulb properly here.
Choosing The Right Onion Varieties For Florida
Selecting the correct variety is the most important decision. Short-day onions are bred for southern climates. They produce large, sweet bulbs when planted at the right time.
- Granex types: These are the classic Vidalia-style onions. They are sweet, mild, and perfect for Florida.
- Texas Super Sweet: A reliable hybrid that produces large, mild bulbs.
- White Bermuda: An old favorite that matures early and stores reasonably well.
- Red Creole: A pungent red onion that holds up well in storage.
- Yellow Granex: The standard for sweet onion lovers.
Avoid long-day varieties like Walla Walla or Spanish onions. They need 14 to 16 hours of daylight to bulb, which Florida never gets during the growing season.
When To Plant Onions In Florida
Timing is everything. Onions are cool-season crops in Florida. They grow during the cooler months and bulb as days lengthen in spring.
- North Florida: Plant sets or transplants from October to December.
- Central Florida: Plant from October through January.
- South Florida: Plant from November through January.
If you plant too late, the heat will arrive before the bulbs mature. If you plant too early, the onions may bolt or produce small bulbs. Aim for a planting date that gives the onions at least 90 days of cool weather.
Starting From Seeds, Sets, Or Transplants
You have three options for starting your onion crop. Each has pros and cons.
Onion Seeds
Starting from seeds gives you the most variety choices. Seeds are inexpensive, but they require more time and care. Sow seeds indoors 8 to 10 weeks before your planned transplant date. Keep them under grow lights or in a sunny window. Harden them off before planting outside.
Onion Sets
Sets are small, dormant bulbs sold in bags. They are the easiest option for beginners. Plant them directly in the garden. Sets are less likely to bolt, but they have fewer variety options. Look for short-day sets specifically labeled for Florida.
Transplants
Transplants are young onion plants sold in bundles. They are more expensive than seeds or sets but give you a head start. Choose transplants that are pencil-thick and healthy. Avoid any that look wilted or yellowed.
Preparing The Soil For Onions
Onions need loose, well-draining soil rich in organic matter. Florida soil is often sandy or heavy with clay. Amend it properly for best results.
- Test your soil pH. Onions prefer a pH between 6.0 and 6.8.
- Add 2 to 3 inches of compost or aged manure to the planting bed.
- Mix in a balanced fertilizer like 10-10-10 at a rate of 1 pound per 100 square feet.
- Rake the bed smooth and remove any rocks or debris.
Raised beds are ideal for onions in Florida. They improve drainage and warm up faster in spring. If you have heavy clay soil, raised beds are almost essential.
How To Plant Onions In Florida
Planting correctly sets the stage for strong growth. Follow these steps for the best results.
- Space rows 12 to 18 inches apart.
- Plant sets or transplants 4 to 6 inches apart within the row.
- Bury the bulb or transplant so the top is just below the soil surface.
- Water thoroughly after planting to settle the soil.
- Mulch with straw or pine straw to retain moisture and suppress weeds.
If you are planting seeds, sow them 1/4 inch deep and thin seedlings to 4 inches apart once they are 2 inches tall. Overcrowding leads to small bulbs.
Watering And Fertilizing Onions
Onions have shallow roots and need consistent moisture. They are not drought-tolerant. Water deeply once or twice a week, depending on rainfall. Aim for about 1 inch of water per week.
Fertilize onions every 2 to 3 weeks during the growing season. Use a nitrogen-rich fertilizer like 21-0-0 or a balanced vegetable fertilizer. Stop fertilizing once the bulbs start to swell and the tops begin to yellow.
Avoid overwatering, which can cause rot. Florida’s winter rains are usually sufficient, but supplement during dry spells. Drip irrigation is the best method because it keeps foliage dry and reduces disease.
Managing Weeds And Pests
Weeds compete with onions for nutrients and water. Keep the bed weed-free by hand pulling or using a shallow hoe. Onion roots are delicate, so be careful not to disturb them.
Common pests in Florida include onion thrips and nematodes. Thrips are tiny insects that suck sap from leaves, causing silvery streaks. Use insecticidal soap or neem oil if you see damage. Nematodes are microscopic worms that attack roots. Rotate crops and use resistant varieties if nematodes are a problem.
Diseases like fungal leaf blight and pink root can occur. Avoid overhead watering and provide good air circulation. Remove any diseased plants immediately.
When To Harvest Onions In Florida
Onions are ready to harvest when the tops start to yellow and fall over. This usually happens in late spring, around April or May in most of Florida. Do not wait until the tops are completely dead.
- Stop watering once the tops begin to fall.
- Gently loosen the soil around the bulbs with a garden fork.
- Pull the onions by hand and shake off excess soil.
- Leave the onions in the garden for a few hours to dry if the weather is dry.
- Move them to a shaded, well-ventilated area for curing.
Harvest in the morning when temperatures are cool. Handle bulbs carefully to avoid bruising. Bruised onions do not store well.
Curing And Storing Onions
Curing is essential for long-term storage. It dries the outer layers and necks, preventing rot. Cure onions for 2 to 3 weeks in a warm, dry place with good air circulation.
- Spread onions in a single layer on a wire rack or screen.
- Keep them out of direct sunlight.
- Once the necks are dry and the outer skin is papery, trim the roots and cut the tops to 1 inch.
- Store in a cool, dark, dry place. Ideal temperature is 40 to 50°F.
Sweet onions like Granex do not store as long as pungent varieties. Use them within 2 to 3 months. Pungent onions like Red Creole can last up to 6 months if stored properly.
Common Mistakes When Growing Onions In Florida
Even experienced gardeners make mistakes. Here are the most common ones to avoid.
- Planting the wrong variety. Always choose short-day onions.
- Planting too late. Onions need cool weather to grow leaves before bulbing.
- Overcrowding. Give each onion enough space to develop a full bulb.
- Overwatering. Too much water leads to rot and disease.
- Skipping fertilizer. Onions are heavy feeders and need regular nutrition.
- Harvesting too early or too late. Watch the tops for the right timing.
Learn from these mistakes and your next crop will be even better.
Tips For Growing Onions In Containers
If you have limited space, you can grow onions in containers. Use a pot that is at least 12 inches deep and wide. Fill it with a high-quality potting mix.
- Choose short-day varieties that are compact.
- Plant sets or transplants 3 to 4 inches apart.
- Water more frequently because containers dry out faster.
- Fertilize every 2 weeks with a liquid fertilizer.
- Place the container in full sun.
Container-grown onions may produce smaller bulbs, but they are still delicious. You can also grow green onions or scallions in containers year-round.
Growing Green Onions In Florida
Green onions, also called scallions, are easy to grow and harvest quickly. You can plant them any time of year in Florida, but fall and spring are best.
- Use sets or seeds of any onion variety.
- Plant them close together, 1 to 2 inches apart.
- Harvest when the tops are 6 to 8 inches tall.
- Cut what you need and let the rest regrow.
Green onions are perfect for beginners. They require less space and time than bulb onions.
Frequently Asked Questions
Can I grow onions in Florida during summer?
No, onions are cool-season crops. Summer heat causes them to bolt or rot. Plant in fall or early winter instead.
What is the best onion variety for South Florida?
Granex types like Texas Super Sweet and Yellow Granex perform well in South Florida’s warm climate.
How long do onions take to grow in Florida?
From planting sets or transplants, onions take about 90 to 120 days to mature. From seeds, add 8 to 10 weeks.
Do onions need full sun in Florida?
Yes, onions need at least 6 to 8 hours of direct sunlight daily. Less sun results in small bulbs.
Can I grow onions from kitchen scraps in Florida?
You can regrow green onions from the root ends in water, but they will not produce large bulbs. For bulb onions, start with seeds, sets, or transplants.
Growing onions in Florida is rewarding when you follow the right steps. Choose short-day varieties, plant at the correct time, and provide consistent care. With a little patience, you will harvest sweet, homegrown onions that taste far better than store-bought. Start your onion patch this fall and enjoy the fruits of your labor next spring.