When to Plant Pennisetum in Washington, IL

Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

By referring to the USDA zone info for Washington it's possible to estimate when it's possible to plant pennisetum.


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.

Since pennisetum are barely cold tolerant you can plant them just a tiny bit earlier in the year than plants that are more sensitive to the cold.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant pennisetum
Possibly ok, but a risky time to plant pennisetum
Probably not a good time to plant pennisetum

The earliest that you can plant pennisetum in Washington 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 pennisetum and expect a good harvest is probably August. If you wait any later than that and your pennisetum may not have a chance to fully mature. If you are starting your pennisetum indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

In Washington the average date of last frost happens on April 15. You can expect an average low temperature of -15°F in the coldest months of winter.

Since the USDA zone info for Washington is not always accurate the actual date of last frost will vary from year to year. Since half of the time in Washington there is a last frost after April 15 be ready to protect your pennisetum in the event of one of those late frosts.

USDA Zone Info for Washington

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)April 15
Average Date of First Frost (fall)October 15
Lowest Expected Low-15°F
Highest Expected Low-10°F

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Washington

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