Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The USDA zone info for Ames should be looked at to determine when it's the best time to plant pentas.

Planting Calendar for Pentas

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

Since pentas require warm weather you need to wait until after the last frost has passed before you can plant them.

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

The last month that you can plant pentas and expect a good harvest is probably August. Any later than that and your pentas may not have a chance to fully mature. You can get started a few weeks earlier by starting your pentas indoors.

Last Frost Date

The average date of last frost is April 15 in Ames. It might get as low as -20°F during the coldest months of winter.

Keep in mind that the actual date of last frost is an average because it is based on the USDA zone info for Ames and it can change quite a bit from year to year. Half of the time in Ames it frosts late in the year after April 15 so be sure to be ready to protect your pentas if you have one of those late frosts.

USDA Zone Info for Ames

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°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 -15°F.

Plants to Grow in Ames

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