When to Plant Tree onions in Windsor Heights, IA

One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By reviewing the USDA zone info for Windsor Heights you should be able to figure out when it's the best time to plant tree onions.


Planting Calendar for Tree onions

Frost tolerance for tree onions: Tolerant of a very small amount of frost.
When to plant: Up to 3 weeks before last frost.

Since tree onions are one of those plants that can tolerate a tiny bit of cold weather you can plant them slightly earlier in the year than other frost tender plants.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant tree onions
Possibly ok, but a risky time to plant tree onions
Probably not a good time to plant tree onions

The earliest that you can plant tree onions in Windsor Heights is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant tree onions and expect a good harvest is probably August. If you wait any later than that and your tree onions may not have a chance to fully mature. You can get started a little bit earlier by starting your tree onions indoors.

Last Frost Date

In Windsor Heights the average date of last frost happens on April 15. It might get as low as 5°F during the coldest months of winter.

It's important to remember that the actual date of last frost is an average because it is based on the USDA zone info for Windsor Heights and it will vary from year to year. Half of the time in Windsor Heights you get a frost after April 15 so make sure that you are ready to protect your tree onions in the event of one of those late frosts.

USDA Zone Info for Windsor Heights

Here is the info for USDA Zone 7b.

Average Date of Last Frost (spring)April 15
Average Date of First Frost (fall)October 15
Lowest Expected Low5°F
Highest Expected Low10°F

This means that on a really cold year, the coldest it will get is 5°F. On most years you should be prepared to experience lows near 10°F.

Plants to Grow in Windsor Heights

You may be interested in your other planting guides for Windsor Heights.