One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

In El Mirage you can estimate when it's the best time 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.

You can plant penstemon a little earlier in the year because they are one of those plants that can tolerate a little bit of cold weather.

The earliest that you can plant penstemon in El Mirage 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. If you wait any later than that and your penstemon may not have a chance to really do well. You can get started a few weeks earlier by starting your penstemon indoors.

Last Frost Date

The average date of last frost is February 15 in El Mirage. You can expect an average low temperature of 25°F in the coldest months of winter.

Since the USDA zone info for El Mirage is just an average the actual date of last frost changes from year to year. Since half of the time in El Mirage there is a last frost after February 15 be ready to protect your penstemon if you have a surprise late frost.

USDA Zone Info for El Mirage

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 El Mirage

You may be interested in your other planting guides for El Mirage.