The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

You should be able to estimate when it's possible to plant pyrethrum by checking out the USDA zone info for Lynden.

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 tells us that you can start planting them earlier than plants that are more sensitive to the cold.

The earliest that you can plant pyrethrum in Lynden 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. If you wait any later than that and your pyrethrum may not have a chance to fully mature. If you are starting your pyrethrum indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

In Lynden the average date of last frost happens on March 15. You should expect an average low temperature of 10°F in the coldest months of winter.

Since the USDA zone info for Lynden is an average the actual date of last frost can change quite a bit from year to year. Half of the time in Lynden it frosts late in the year after March 15 so always be ready to cover your pyrethrum in the event of a surprise late frost.

USDA Zone Info for Lynden

Here is the info for USDA Zone 8a.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	10°F
Highest Expected Low	15°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 15°F.

Plants to Grow in Lynden

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