Onions are a wonderful addition to your garden! They take up minimal space, are easy to plant and maintain, and can store all winter. They also pair well with other produce in your garden and can be used in a variety of dishes. Being a root vegetable, onions can be planted early in the season, which helps satisfy the need to get hands in the dirt before the soil is ready for other crops like tomatoes. The first step is to determine what type of onion you want to grow, with options including yellow, red, and sweet varieties. Onions are a cool weather crop that can be planted when soil temperatures reach 50 degrees F. They should be planted 1/4 – 1/2 inch deep, 3-4 inches apart, in rows 12-18 inches apart, and watered once a week if rain is inadequate. Onions can be harvested when the tops start to die and tip over, and then cured before storing to promote longevity and prevent rot.
Key Takeaways
- Onions are an easy-to-grow, versatile vegetable that can be planted early in the season.
- Different varieties of onions, including yellow, red, and sweet, can be selected to suit your climate and preferences.
- Proper planting depth, spacing, and watering are crucial for successful onion cultivation.
- Onions can be harvested and cured to extend their storage life throughout the winter.
- Onions can be used in a variety of dishes and pair well with other garden produce.
Understanding Onion Varieties
Onions are photoperiodic, meaning they are sensitive to daylight, so different varieties have been bred for varying day lengths. The border between long-day onions and short-day onions lies roughly at 36 degrees north latitude. North of that, plant long-day types; south of it, plant short-day onions. Or, try “day-neutral” (also known as intermediate) varieties, which yield an excellent crop anywhere, regardless of day length.
Long-Day Onion Varieties
Some examples of long-day onion varieties include ‘Yellow Sweet Spanish’, ‘First Edition’, ‘Red Wethersfield’, ‘Aisa Craig’, and ‘Walla Walla’. These types are well-suited for growing in regions with longer summer days, typically found in northern climates.
Short-Day Onion Varieties
In contrast, short-day onion varieties include ‘Stuttgarter’, ‘White Bermuda’, ‘Red Burgundy’, ‘Crystal Wax White Bermuda’, and ‘Texas 1015-Y Supersweet’. These varieties thrive in southern regions with shorter daylight hours during the growing season.
Day-Neutral or Intermediate Varieties
For gardeners seeking a more versatile option, day-neutral or intermediate onion varieties like ‘Candy’, ‘Red Stockton’, and ‘Super Star’ can perform well across a range of day lengths, making them a reliable choice regardless of location.
Preparing the Soil for Onion Cultivation
Onions thrive in well-drained soil with a pH between 6.0 and 7.0, along with a high organic matter content. Proper soil preparation is crucial for ensuring optimal onion soil requirements, onion soil pH, and onion soil nutrients.
Soil pH and Nutrient Requirements
Phosphorus (P) and potassium (K) should be added based on soil test recommendations, as many onion soil nutrients are already present in sufficient quantities in Minnesota soils. Onions have a high demand for nitrogen, but excessive nitrogen can lead to late maturity, large necks, soft bulbs, and poor storage quality.
Incorporating Organic Matter
Gardeners can improve their soil’s onion organic matter content by adding well-rotted manure or compost in the spring or fall. Fresh manure should be avoided, as it may contain harmful bacteria and increase weed problems. Side dressing with urea (45-0-0) fertilizer at a rate of 0.25 to 0.5 pound per 25 feet of row can be done once or twice during the growing season to provide additional nitrogen.
Planting Onions from Seeds, Sets, or Transplants
Onions can be grown from several different methods, each with its own advantages. Gardeners can choose to sow onion seeds, plant onion sets, or transplant onion seedlings, depending on their preferences and growing conditions.
Growing Onions from Seeds
Sowing onion seeds early in the spring, as soon as the soil is workable, is the most cost-effective way to grow onions from seed. This method requires thinning the seedlings as they grow, but it allows for a wider variety of onion cultivars. Sowing seeds directly in the garden takes longer for the bulbs to form compared to sets or transplants.
Planting Onion Sets
Planting onion sets, which are immature bulbs grown the previous season, is the most common way to grow onions. Sets are easy to plant and space out, and they don’t require thinning. When planting sets, the roots should be trimmed to 2 inches and the tops to 4 inches. The sets should be planted with the pointy tip up, 2 inches deep and 3 to 4 inches apart in rows 12 to 16 inches apart.
Transplanting Onion Seedlings
Transplanting onion seedlings, which are young plants started earlier in the season, is the favorite method for many gardeners. Onion transplants tend to be more successful and produce full-sized onions compared to growing from seed or sets. When transplanting, the roots should be trimmed to 2 inches and the tops to 4 inches, just like with sets.
How to Grow Onions: Care and Maintenance
Providing the right care and maintenance is crucial for growing healthy, bountiful onions. Let’s explore the key aspects of caring for onions, from watering to weed control and fertilizing.
Watering Onions
Onions are shallow-rooted vegetables that require a consistent supply of water for good growth. They need about 1 inch of water per square foot per week, including rainwater. Keeping the soil consistently moist is important, as onions recover well from drought but inconsistent watering onions can affect bulb development.
Weed Control and Mulching
Weeds can be a challenge for onion growers, as they can compete for nutrients and water. Hoeing between rows is an effective way to control onion weed control, but care should be taken to avoid going too deep and damaging the shallow onion roots. Applying a light mulch of organic material like grass clippings or straw can help retain moisture and suppress onion mulching.
Fertilizing Onions
Onions are heavy feeders and require regular fertilization to thrive. Side dressing with urea (45-0-0) fertilizer at a rate of 0.25 to 0.5 pound per 25 feet of row is recommended once or twice during the growing season to provide additional onion fertilizing. This will help ensure the plants have the necessary nutrients for optimal growth and bulb development.
Companion Planting and Pest Management
Onions can help deter a variety of pests in the garden due to their strong scent. They make great onion companion plants for plants in the cabbage family, as well as lettuce, tomatoes, and strawberries, helping to repel aphids, cabbage worms, and Japanese beetles. However, onions should not be planted near peas, beans, or asparagus, as they can potentially contaminate the flavor.
Common Pests and Diseases
Some common onion pests that can affect onions include thrips, which can be controlled with insecticidal soap, and onion maggots, which can be deterred by covering the crop with fine mesh netting or row covers. Onions are also susceptible to diseases like onion diseases such as downy mildew, which can be managed through proper spacing, watering, and rotation of the crop location.
Conclusion
Growing onions can be a rewarding and easy addition to any home garden. By choosing the right onion variety for your climate, preparing the soil properly, and providing the right care and maintenance, gardeners can enjoy a bountiful onion harvest. Proper planting, watering, weed control, and fertilization are key to ensuring healthy, full-sized onions.
Onions can also be beneficial companions to other vegetables in the garden, helping to deter pests. With a little bit of effort, gardeners can enjoy the convenience and flavor of homegrown onions for months, even throughout the winter, by properly curing and storing them. Overall, onions are a versatile and low-maintenance crop that can be a great addition to any beginner’s vegetable garden.