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.

The best time to plant penstemon in Shafter should be determined by using 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.

Penstemon do well in some cold which tells us that you can plant them just a bit earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant penstemon in Shafter 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 grow to maturity. 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

On average the last frost when the weather gets warmer is on February 15 in Shafter. It might get as low as 20°F during the coldest months of winter.

Since the USDA zone info for Shafter is just an average the actual date of last frost changes from year to year. Half of the time in Shafter it frosts late in the year after February 15 so make sure that you are prepared to protect your penstemon if you have a surprise late frost.

USDA Zone Info for Shafter

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 Low	20°F
Highest Expected Low	25°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 Shafter

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