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Flowers, Fruits, and Frass

Snow, Rain, and Onions

I was going to write about preparing the garden bed, but then it snowed. Then I thought I could write about seeding in the snow, and then it melted.

This weather has been cruel keeping me indoors.

According to the Illinois State Water Survey: Illinois Climate Network, the temperature of our soil is above 40 degrees, and many crops are ready to be planted in the garden as soon as the soil dries out. One cool season crop that I have never written about is onion.

Onions are a fantastic cool season crop to grow in your garden or landscape, and can be planted as soon as soon as the soil is workable. They can even tolerate light frosts. After you have acquired onion sets from the garden center, sort them by size, one pile for greater than a dime and one pile for smaller than a dime. The larger ones may flower too quickly and will be more fitting to the shorter growing schedule of green onions. The small sets will be used to grow the dry bulbs.

Plant the larger bulb sets one inch deep and close enough to touch. When they are 4 inches tall, bring the soil up an inch above the base to create the white stems we often see in green onions. Plant another crop two weeks after so that you will have another later harvest. These green bunching onions can be harvested in as little as three to four weeks.

The smaller bulbs should be planted one inch deep and two to four inches apart. There is no need to hill soil above the base as the season progresses. These onions mature in about 90-100 days from sets. From late July to early August, plants will fall over and the tops become yellow. Pull onions, braid the tops and place under a cover to dry for about three to four weeks. After drying, cut off the tops and store.

Onions will respond well to added organic matter at the time of planting and require consistent moisture because of their shallow roots.

A side dress of fertilizer during the growing season is encouraged.

Onion plants repel a variety of insects and may be useful if planted next to carrots, cucumbers, kale, peppers, roses, strawberries and tomatoes.