One of the first steps you take when you are making a decision about your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The earliest that you can plant pennisetum in Riverside should be figured out by using 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.

Since pennisetum are barely cold tolerant you can plant them just a tiny bit earlier in the year than other frost tender plants.

The earliest that you can plant pennisetum in Riverside 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. You probably don't want to wait any later than that or else 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 couple of weeks earlier.

Last Frost Date

In Riverside the average date of last frost happens on April 15. In the coldest months of winter you can expect an average low temperature of -10°F.

It's important to remember that USDA zone info for Riverside is not always accurate and the actual date of last frost can change quite a bit from year to year. Since half of the time in Riverside last frost occurs after April 15 be ready to protect your pennisetum if you have a surprise late frost.

USDA Zone Info for Riverside

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°F

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Riverside

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