Be sure the container has a drainage hole in the bottom. If you choose to grow onions in pots, choose a large mouthed pot. Mix the fertilizer in the regular irrigation water at a rate of 1 to 2 teaspoons in 1 gallon of water. Water is an important to growing onions in container gardens because your container onions will have little access to naturally stored rainfall from surrounding soil like onions grown in the ground do. How-to Guide: Growing Onions in Containers Growing Onions from Seeds. You can also grow onions from sets, which are small onions used for growing. Because you need several onions planted to get a decent crop, attempting to grow onions in pots that are only 5 or 6 inches (12.5 to 15 cm.) Just because you have limited space doesn’t mean that you need to limit what you grow. When growing onions in pots from seed, use the same spacing you would for sets; just water the soil generously after the seeds have planted. Growing indoor onions or growing onions in a tub on the patio is fun and easy. If you are growing indoor onions and don’t have a location with adequate sunlight, you can supplement the light with fluorescent bulbs set close to the onions. What Is A Rain Chain – How Do Rain Chains Work In Gardens, Are Red Onions Easy To Grow: Tips On Growing Red Onions, Vegetables In A 5-Gallon Bucket: How To Grow Vegetables In A Bucket, Prickly Kale Leaves – Does Kale Have Thorns, Corn Husk Wreath Ideas: How To Make A Corn Husk Wreath, DIY Air Plant Wreaths: Wreath Making With Air Plants, Dwarf Fruit Trees – A Planting Guide For Fruit Trees In Containers, Thanksgiving Tradition: Turning Homegrown Pumpkins Into Pie, Growing Thanksgiving Dinner – Must Have Turkey Side Dishes, Interesting Uses For Pecans: What To Do With Pecans, The Bountiful Garden: Bringing The Garden To Thanksgiving. Although you can plant onion seeds or transplants, onion bulbs, also known as sets, are disease resistant and easy to plant and grow. of water a week, perhaps even more in hot weather. Wait to plant onions until the soil temperature reaches about 60 degrees. Now that you know how to grow onions in container gardens, you have no excuse not to. Onions grown in containers will need at least 2 – 3 inches (5 to 7.5 cm.) If you want to harvest full-size onions, allow 3 to 5 inches. Read this article on growing onions for more information on basic onion care. Onions (Allium cepa) are hardy vegetables that are typically grown outdoors, but planting onions in a pot for indoor or patio growing is also a practical option. Check your onions daily, and if the top of the soil is dry to the touch, give them some water. How To Grow Onions In Containers BEST CONTAINERS FOR GROWING ONIONS. In My Garden, Why Are My Onion Bulbs Small? You might also wish to check with local garden centers: Given a few months' notice, they may be able to grow them for you to order. WHEN TO GROW ONIONS. Red Wethersfield onions are a type of long-day onion, which requires between 14 and 16 hours of sunlight to form bulbs. For example, if you want small onions, plant the seeds 1 to 1 1/2 inches apart. Plant onion sets in early spring; the plants tolerate frost and require a period of cool weather to grow. Just make sure that you put holes in the bottom of the tub to provide drainage. If you want to harvest full-size onions, allow 3 to 5 inches. Push the sets about 1 inch deep into the soil with the points facing up. If you want to harvest large, mature onions, stop watering when the onions reach the desired size, and then harvest them when the tops begin to turn brown in mid- to late summer. Spacing depends on how big you want the onions at harvest. University of the District of Columbia Cooperative Extension Service: Onions, The National Gardening Association: Planting Onions, Arizona Cooperative Extension: Growing Vegetables in Containers, Planting Red Wethersfield Onions in Containers. Plant onion sets and transplants about 2-3 inches deep; and 1-2 inches apart. Harvest small onions when the tops are at least 6 inches tall. It needs to be at least 10 inches (25.5 cm.) Really, the only difference between what you do when you grow onions in the ground and when you grow onions in pots is choosing the container you’ll be growing them in. Water the onions when the top 1 inch of soil feels dry to the touch, adding water slowly until liquid trickles through the drainage hole. open soil around them to grow properly. Sign up for our newsletter. A shop light on an adjustable chain makes an excellent grow light for people who growing indoor onions. f planting in rows, allow at least 12 inches apart. Growing onions in containers allows you to be growing onions indoors or in a small space in your backyard. Place the container where the onions are exposed to full sunlight. You can also grow onions in 5 gallon (19 L.) buckets, but realize that you may only be able to grow 3 or 4 onions per bucket as onions need at least 3 inches (7.5 cm.) Fill a clean pot with a good quality commercial potting soil containing ingredients such as peat and vermiculite or perlite. of water a week, perhaps even more in hot weather. You can buy onions seeds from any gardening store. Find more gardening information on Gardening Know How: Keep up to date with all that's happening in and around the garden. Because plastic tubs are much cheaper than a comparable sized pot, growing onions in a tub is economical and efficient. You need good soil, adequate drainage, good fertilizer and plenty of light. For example, if you want small onions, plant the seeds 1 to 1 1/2 inches apart. Red onions, readily available in bulb form, are a good choice if you prefer a mild, sweet, crisp onion. If you want to choose a specific cultivar of red onion to grow, you'll need to exercise some ingenuity. Growing Onions from Sets. Many people would love to grow onions, but due to a small garden or perhaps no garden at all, they just don’t have the space. For indoor growing, or if you're in a mild climate with no hard freezes, you can plant onion sets in autumn. Whether you decide to growing onions in a tub or in pots, it’s essential that you put the onion container somewhere that gets six to seven hours of light. wide would be cumbersome. How Long Does It Take for Onions to Fully Grow? Fertilize the onion sets two to four weeks after planting and every two weeks thereafter, using a balanced, water-soluble fertilizer with a ratio such as 8-8-8 or 10-10-10. deep, but should be several feet (1 m.) wide so that you’ll be able to plant enough onions to make it worth your while. They'll germinate in a week or so. While onion bulbs come in several varieties, they are generally not sold by variety, but by color, such as white, yellow or red. Water is an important to growing onions in container gardens because your container onions will have little access to naturally stored rainfall from surrounding soil like onions grown in the ground do. If any fail to germinate, you can re-plant that spot with a new seed. Prepare a large container with potting soil and dig in a slow-release fertilizer to help roots get a good start.