Love them or hate them? Onions are one of those produce items that people tend to have a strong opinion about, making them a garden idea that you are strongly opinionated about too.
But for those of you that decide to grow them in the garden here are some great tips to make the season more successful.
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1. Plant the right variety for your area
There are three types of onions, classified by the length of daylight needed by the plants to begin forming bulbs: short-, intermediate-, or long-day. Short-day plants start the bulbing process when the day length reaches 10-12 hours; intermediate onions are the most common and they start putting out bulbs when the day lengths are 12-14 hours; long-day onions need 14-16 hours. Short day plants are best suited for growing in southern climates during winter and early spring months when the days are short. Intermediate types grow well just about anywhere; long-day onions are typically grown in the northern climates where they have time to grow foliage before initiating bulb development.
There are three types of onions, classified by the length of daylight needed by the plants to begin forming bulbs: short-, intermediate-, or long-day. Short-day plants start the bulbing process when the day length reaches 10-12 hours; intermediate onions are the most common and they start putting out bulbs when the day lengths are 12-14 hours; long-day onions need 14-16 hours. Short day plants are best suited for growing in southern climates during winter and early spring months when the days are short. Intermediate types grow well just about anywhere; long-day onions are typically grown in the northern climates where they have time to grow foliage before initiating bulb development.
It's somewhat tricky to understand the differences, and what types grow best in what areas, but Fine Gardening helps to explain it well.
2. Start seeds indoors in late winter
Growing onions from seed is the least expensive method and gives you the most choices of varieties. In late winter start onion seeds inside under fluorescent lights. With bulbing varieties transplant seedlings outside about 4-6 weeks before the last frost.
Growing onions from seed is the least expensive method and gives you the most choices of varieties. In late winter start onion seeds inside under fluorescent lights. With bulbing varieties transplant seedlings outside about 4-6 weeks before the last frost.
3. Plant in loose soil
Onions, like other veggies that grow underground (carrots, garlic, beets, potatoes, etc.) need to have friable, loose soil to form nice looking vegetables. If they encounter rocks or other obstacles like large soil clods, they will become deformed. To avoid this work the garden bed at least 12" down.
Onions, like other veggies that grow underground (carrots, garlic, beets, potatoes, etc.) need to have friable, loose soil to form nice looking vegetables. If they encounter rocks or other obstacles like large soil clods, they will become deformed. To avoid this work the garden bed at least 12" down.
4. Fertilize carefully
When you first plant your onions they need plenty of phosphorus and potassium to encourage good root growth. Apply a balanced fertilizer to the garden beds before planting; a 10-20-10 is best. About 3 weeks after planting switch to a nitrogen-heavy fertilizer to promote foliage growth. When plants begin to bulb -- you'll see the soil begin to crack around the base of the plant -- stop fertilizing. At this point, the plant has all the nutrients it needs.
When you first plant your onions they need plenty of phosphorus and potassium to encourage good root growth. Apply a balanced fertilizer to the garden beds before planting; a 10-20-10 is best. About 3 weeks after planting switch to a nitrogen-heavy fertilizer to promote foliage growth. When plants begin to bulb -- you'll see the soil begin to crack around the base of the plant -- stop fertilizing. At this point, the plant has all the nutrients it needs.
5. Avoid overhead watering
Once the tops start to grow, they can be very susceptible to disease and fungal problems if there is water on the foliage. Avoid watering from above it possible. Instead, use a soaker hose or drip irrigation that puts water right on the soil to soak into the root zone.
Once the tops start to grow, they can be very susceptible to disease and fungal problems if there is water on the foliage. Avoid watering from above it possible. Instead, use a soaker hose or drip irrigation that puts water right on the soil to soak into the root zone.
6. Watch closely for disease
Chances are high, unfortunately, that your onions will become infected with some sort of disease during the growing season. Bacterial and fungal spores are common during the growing cycle, especially if it is particularly rainy and wet. Proactively apply a protective fungicide (organic or conventional) biweekly to prevent spores from spreading and multiplying. The Ontario Ministry of Agriculture, Food and Rural Affairs can help you identify diseases if you need assistance.
Chances are high, unfortunately, that your onions will become infected with some sort of disease during the growing season. Bacterial and fungal spores are common during the growing cycle, especially if it is particularly rainy and wet. Proactively apply a protective fungicide (organic or conventional) biweekly to prevent spores from spreading and multiplying. The Ontario Ministry of Agriculture, Food and Rural Affairs can help you identify diseases if you need assistance.
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7. Harvest must be followed by a curing period
When the leaves on your onion plants begin to droop, it's time to harvest. This happens because the neck of the onion can no longer support the foliage and signifies maturity. Dig the onions out of the ground and lay them out in rows where they have air circulation. If in the direct sun cover each onion with the foliage from the one next to it to prevent sunburn. When the outside leaf is nice and dry, clip the foliage about 1" above the bulb and trim the roots. Now you can store them without worry of decay or rot.
When the leaves on your onion plants begin to droop, it's time to harvest. This happens because the neck of the onion can no longer support the foliage and signifies maturity. Dig the onions out of the ground and lay them out in rows where they have air circulation. If in the direct sun cover each onion with the foliage from the one next to it to prevent sunburn. When the outside leaf is nice and dry, clip the foliage about 1" above the bulb and trim the roots. Now you can store them without worry of decay or rot.