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

One way of figuring out when it's possible to plant pentas is to use the USDA zone info for Bismarck.

Planting Calendar for Pentas

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

You should not plant pentas until after all chance of frost has passed because they do not do well in cold weather.

The earliest that you can plant pentas in Bismarck is May. However, you really should wait until June 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 grow to maturity. You can get started a few weeks earlier by starting your pentas indoors.

Last Frost Date

In Bismarck the average date of last frost happens on May 15. It might get as low as -30°F during the coldest months of winter.

Just be sure to remember that the actual date of last frost is an average because it is based on the USDA zone info for Bismarck and it is different every year. Half of the time in Bismarck it frosts late in the year after May 15 so make sure that you are prepared to protect your pentas in the event of one of those late frosts.

USDA Zone Info for Bismarck

Here is the info for USDA Zone 4a.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-30°F
Highest Expected Low	-25°F

This means that on a really cold year, the coldest it will get is -30°F. On most years you should be prepared to experience lows near -25°F.

Plants to Grow in Bismarck

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