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When to Plant Tree onions in Barstow, CA

One of the first steps you take when you are making a decision about 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.

The first opportunity to plant tree onions in Barstow should be figured out by looking at the USDA zone info.


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 are one of those plants that can tolerate a tiny bit of cold weather which means that you can start planting them slightly earlier 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 Barstow 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. You probably don't want to wait any later than that or else your tree onions may not have a chance to fully mature. If you are starting your tree onions indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

In Barstow the average date of last frost happens on February 15. It might get as low as 20°F during the coldest months of winter.

Remember that USDA zone info for Barstow may not be accurate from year to year and the actual date of last frost can change quite a bit from year to year. Since half of the time in Barstow last frost occurs after February 15 be ready to protect your tree onions in the event of one of those late frosts.

USDA Zone Info for Barstow

Here is the info for USDA Zone 9a.

Average Date of Last Frost (spring)February 15
Average Date of First Frost (fall)December 15
Lowest Expected Low20°F
Highest Expected Low25°F

This means that on a really cold year, the coldest it will get is 20°F. On most years you should be prepared to experience lows near 25°F.

Plants to Grow in Barstow

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