Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A common way of making a decision about when it's the best time to plant pyrethrum is to look at the USDA zone info for Potsdam.

Planting Calendar for Pyrethrum

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

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

The earliest that you can plant pyrethrum in Potsdam 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 fully mature. 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 Potsdam. You should expect an average low temperature of -25°F in the coldest months of winter.

Keep in mind that the actual date of last frost is an average because it is based on the USDA zone info for Potsdam and it can change quite a bit from year to year. Since half of the time in Potsdam last frost occurs after May 15 be ready to cover your pyrethrum in the event of a surprise late frost.

USDA Zone Info for Potsdam

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Potsdam

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