The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

It's possible to figure out when it's the best time to plant pyrethrum by referring to the USDA zone info for West Richland.

Planting Calendar for Pyrethrum

Frost tolerance for pyrethrum:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Pyrethrum are one of those plants that can tolerate a little bit of cold weather which means that you can plant them a little bit earlier than other plants that might not handle the cold.

The earliest that you can plant pyrethrum in West Richland is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant pyrethrum and expect a good harvest is probably September. Any later than that and your pyrethrum may not have a chance to really do well. If you are starting your pyrethrum indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

On average the last frost is on April 15 in West Richland. You should expect an average low temperature of 0°F in the coldest months of winter.

Keep in mind that USDA zone info for West Richland is an average and the actual date of last frost will vary from year to year. Since half of the time in West Richland there is a last frost after April 15 be ready to cover your pyrethrum in the event of a surprise late frost.

USDA Zone Info for West Richland

Here is the info for USDA Zone 7a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	0°F
Highest Expected Low	5°F

This means that on a really cold year, the coldest it will get is 0°F. On most years you should be prepared to experience lows near 5°F.

Plants to Grow in West Richland

You may be interested in your other planting guides for West Richland.