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

In West Covina you can estimate when to plant penstemon by looking at the USDA zone info.

Planting Calendar for Penstemon

Frost tolerance for penstemon:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Since penstemon do well in moderate cold you can plant them a little bit earlier in the year than more sensitive plants.

The earliest that you can plant penstemon in West Covina is January. However, you really should wait until February if you don't want to take any chances.

The last month that you can plant penstemon and expect a good harvest is probably October. You probably don't want to wait any later than that or else your penstemon may not have a chance to fully mature. If you are starting your penstemon indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

The average date of last frost is January 31 in West Covina. You should expect an average low temperature of 30°F in the coldest months of winter.

Keep in mind that USDA zone info for West Covina is an average and the actual date of last frost can change quite a bit from year to year. Half of the time in West Covina there is a last frost after January 31 so make sure that you are ready to protect your penstemon 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.