The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The first chance to plant welsh onion in Covina can be determined by using the USDA zone info.

Planting Calendar for Welsh onion

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

Since welsh onion 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.

The earliest that you can plant welsh onion in Covina 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 welsh onion and expect a good harvest is probably September. You probably don't want to wait any later than that or else your welsh onion may not have a chance to fully mature. Starting your welsh onion indoors is a great way to get them started a little bit earlier.

Last Frost Date

In Covina the average date of last frost happens on January 31. In the coldest months of winter you should expect an average low temperature of 30°F.

Just be sure to remember that USDA zone info for Covina is just an average and the actual date of last frost changes from year to year. Since half of the time in Covina there is a last frost after January 31 be ready to cover your welsh onion if you have a surprise late frost.

USDA Zone Info for Covina

Here is the info for USDA Zone 10a.

Average Date of Last Frost (spring)	January 31
Average Date of First Frost (fall)	December 15
Lowest Expected Low	30°F
Highest Expected Low	35°F

This means that on a really cold year, the coldest it will get is 30°F. On most years you should be prepared to experience lows near 35°F.

Plants to Grow in Covina

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