The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

You will be able to figure out when it's the best time to plant pentas by using the USDA zone info for Tucson.

Planting Calendar for Pentas

Frost tolerance for pentas:	Not tolerant of frost.
When to plant:	After all chance of frost has passed.

Pentas require warm weather which means that it's important to wait until it warms up after all chance of frost has passed before you can plant them.

The earliest that you can plant pentas in Tucson is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant pentas and expect a good harvest is probably September. You probably don't want to wait any later than that or else your pentas may not have a chance to grow to maturity. If you are starting your pentas indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

In Tucson the average date of last frost happens on February 15. It might get as low as 25°F during the coldest months of winter.

Since the USDA zone info for Tucson is an average the actual date of last frost changes from year to year. Half of the time in Tucson it frosts late in the year after February 15 so make sure that you are ready to cover your pentas in the event of one of those late frosts.

USDA Zone Info for Tucson

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 Tucson

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