One of the first steps you take when you are getting a good idea your gardening schedule is find your 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.

By referring to the USDA zone info for Calimesa you will be able to estimate when 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.

Tree onions do ok in mild 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 Calimesa is February. However, you really should wait until March 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 September. If you wait any later than that and 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

The average date of last frost is February 15 in Calimesa. In the coldest months of winter you should expect an average low temperature of 25°F.

Since the USDA zone info for Calimesa is not always accurate the actual date of last frost is different every year. Since half of the time in Calimesa last frost occurs after February 15 be ready to protect your tree onions if you have a surprise late frost.

USDA Zone Info for Calimesa

Here is the info for USDA Zone 9b.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	25°F
Highest Expected Low	30°F

This means that on a really cold year, the coldest it will get is 25°F. On most years you should be prepared to experience lows near 30°F.

Plants to Grow in Calimesa

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