Onion plants are a member of the Allium family and are grown for their edible bulbs. They are hardy, cold-tolerant, and easy to grow. Onions grow best in full sun in well-drained soil with a pH of 6.0-6.5. They require regular watering and should be fertilized every 2-3 weeks with a balanced fertilizer. Onions grow from small bulbs that are planted in the spring and harvested in the late summer or early fall. The plants have long, hollow leaves that grow from the base of the bulb and reach up to two feet tall. The bulbs are usually white, yellow, or red, depending on the variety.
Planning Your Garden With Onions
As you plan your garden, it's important to think about the spacing, size, light, and nutrient requirements of all of your plant and how they'll grow together.
Some plants require more water than others, while other plants require dry soil. At the same time, some plants prefer full sun, and other plants need the shade to survive.
By studying what each plant requires and planning ahead where all of your plants will grow best, you can optimize your garden space.
| Life Cycle | Onions are usually grown as annuals. |
| USDA Zone | Onions are hardy in USDA Zones 3-10. |
| Cold Tolerance | Onions are cold tolerant and can survive temperatures down to 20. |
| Days to harvest | Onions typically take between 90 and 120 days to reach maturity and be ready for harvest. |
| Average size | The average size of a full grown onion plant is between 12 and 18 inches tall. |
| Spacing requirements | Onions need about 4-6 inches of space between plants in order for them to grow properly. |
| Sun tolerance | Onions are tolerant to full sun, but they do best with at least 6 hours of direct sunlight per day. |
| Shade tolerance | Onions are tolerant of partial shade, but they grow best in full sun. |
| Water requirements | Onions require a consistent supply of water throughout their growing season. They should be watered deeply and regularly, about 1-2 inches of water per week. Onions prefer slightly acidic soil with a pH of 6.0-6.5. If the soil is too alkaline, it can cause the onions to form small bulbs and have a bitter flavor. It is important to keep the soil evenly moist, but not soggy, to prevent the onions from becoming stunted or developing diseases. |
| Fertilizer | The amount of fertilizer you should use when growing onions depends on the type of fertilizer you are using and the soil conditions. Generally, a balanced fertilizer with an N-P-K ratio of 10-10-10 is recommended. Apply 1/2 to 1 pound of fertilizer per 100 square feet of garden space. |
| Soil pH | Onions prefer a slightly acidic soil with a pH of 6.0 to 6.5. |
Why Onions are Popular
People like to grow onions because they are easy to grow, require little maintenance, and are very versatile in the kitchen. Onions are a key ingredient in many dishes and can be used in a variety of ways. They are also a great source of vitamins and minerals and can help to boost immune health.
Companion Plants For Onions
Companion planting is a great way to maximize your garden space and get the most out of your plants. By planting certain plants together, you can help each other thrive. In some cases, you can even help each other repel pests.
Popular companion plants for onions include:
Common Pests For Onions
Plant pests are a common problem for gardeners. By understanding what pests are common for your plants, you can take steps to prevent them from damaging your plants.
When you grow onions, keep an eye out for these common pests:
- thrips
- onion maggots
USDA Zones
USDA zones are a popular way of determining which plants can grow in your area. Zones tell you when your average first and last frost date are, as well as how cold you can expect it to get in the winter.
Our site works best if you choose your zone from the list below. If you do not know your USDA zone, then you can use our zone map.
