One of the best tools that you have as gardeners to help us estimate your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

A way of making a decision about when it's the best time to plant tree onions is to look at the USDA zone info for Alma.

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.

Tree onions do well in a tiny bit of cold which means that you can plant them slightly earlier in the year than more sensitive plants.

The earliest that you can plant tree onions in Alma 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. You probably don't want to wait any later than that or else your tree onions may not have a chance to grow to maturity. Starting your tree onions indoors is a great way to get them started a little bit earlier.

Last Frost Date

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

Always keep in mind that USDA zone info for Alma is not always accurate and the actual date of last frost is different every year. Since half of the time in Alma last frost occurs after April 15 be ready to cover your tree onions if you have one of those late frosts.

USDA Zone Info for Alma

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 Low	5°F
Highest Expected Low	10°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 Alma

You may be interested in your other planting guides for Alma.