One of the first steps you take when you are getting a good idea 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 best time to plant pennisetum in Zone 4b should be estimated by referring to the USDA zone info.

Planting Calendar for Pennisetum

Frost tolerance for pennisetum:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Pennisetum can survive in very little cold which means that you can plant them just a tiny bit earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant pennisetum in Zone 4b 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 pennisetum and expect a good harvest is probably August. You probably don't want to wait any later than that or else your pennisetum may not have a chance to really do well. You can get started a little bit earlier by starting your pennisetum indoors.

Last Frost Date

On average the last frost when the weather gets warmer is on May 15 in Zone 4b. In the coldest months of winter you can expect an average low temperature of -25°F.

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 Zone 4b and it will vary from year to year. Half of the time in Zone 4b you get surprised by a frost after May 15 so be sure to be ready to protect your pennisetum if you have a late frost.

USDA Zone Info for Zone 4b

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°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 -20°F.

Plants to Grow in Zone 4b

You may be interested in your other planting guides for Zone 4b.