One of the best tools that you have as gardeners to help us figure out 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.

By using the USDA zone info for West Covina you should be able to determine when it's the best time to plant euphorbia.

Planting Calendar for Euphorbia

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

Since euphorbia are one of those plants that can tolerate a tiny bit of cold weather you can plant them slightly earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant euphorbia in West 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 euphorbia and expect a good harvest is probably September. If you wait any later than that and your euphorbia may not have a chance to fully mature. If you are starting your euphorbia indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

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

Since the USDA zone info for West Covina is not always accurate the actual date of last frost can change quite a bit from year to year. Half of the time in West Covina you get surprised by a frost after January 31 so make sure that you are prepared to cover your euphorbia in the event of a surprise late frost.

USDA Zone Info for West 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 West Covina

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