When can I plant Pyrethrum in Zone 4a

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

In Zone 4a you can figure out when it's the best time to plant pyrethrum by looking at the USDA zone info.


Planting Calendar for Pyrethrum

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

You can plant pyrethrum a bit earlier in the year because they are one of those plants that can tolerate a little bit of cold weather.

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

The earliest that you can plant pyrethrum in Zone 4a 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 pyrethrum and expect a good harvest is probably August. If you wait any later than that and your pyrethrum may not have a chance to really do well. You can get started a few weeks earlier by starting your pyrethrum indoors.

Last Frost Date

On average the last frost has passed is on May 15 in Zone 4a. We can expect an average low temperature of -30°F in the coldest months of winter.

Since the USDA zone info for Zone 4a is not always accurate our actual date of last frost changes from year to year. Half of the time in Zone 4a there is a last frost after May 15 so make sure that you are prepared to protect your pyrethrum in the event of a surprise late frost.

USDA Zone Info for Zone 4a

Here is the info for USDA Zone 4a.

Average Date of Last Frost (spring)May 15
Average Date of First Frost (fall)September 15
Lowest Expected Low-30°F
Highest Expected Low-25°F

This means that on a really cold year, the coldest it will get is -30°F. On most years you should be prepared to experience lows near -25°F.

Plants to Grow in Zone 4a

You may be interested in our other planting guides for Zone 4a.