One of the first steps you take when you are making a decision about your gardening schedule is find your 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 first opportunity to plant penstemon in Scottsdale should be estimated by checking out 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 bit earlier in the year than other frost tender plants.

The earliest that you can plant penstemon in Scottsdale 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 few weeks earlier.

Last Frost Date

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

Remember that USDA zone info for Scottsdale is an average and the actual date of last frost changes from year to year. Half of the time in Scottsdale last frost occurs after February 15 so always be ready to protect your penstemon in the event of a surprise late frost.

USDA Zone Info for Scottsdale

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 Scottsdale

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