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.

A common way of estimating when you can plant pyrethrum is to consult the USDA zone info for Frederick.

Planting Calendar for Pyrethrum

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

Since pyrethrum are moderately cold tolerant you can plant them just a bit earlier in the year than other plants that might not handle the cold.

The earliest that you can plant pyrethrum in Frederick 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 grow to maturity. Starting your pyrethrum indoors is a great way to get them started a little bit earlier.

Last Frost Date

On average the last frost is on April 15 in Frederick. In the coldest months of winter you should expect an average low temperature of -5°F.

Since the USDA zone info for Frederick is not always accurate the actual date of last frost changes from year to year. Half of the time in Frederick you get surprised by a frost after April 15 so be sure to be ready to protect your pyrethrum if you have a surprise late frost.

USDA Zone Info for Frederick

Here is the info for USDA Zone 6b.

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

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

Plants to Grow in Frederick

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