One of the first steps you take when you are getting a good idea your gardening schedule is find your USDA Zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

In Manassas you can determine when it's a good idea to plant pyrethrum by looking at the USDA zone info.

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 start planting them earlier than plants that are more sensitive to the cold.

The earliest that you can plant pyrethrum in Manassas 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. You can get started a few weeks earlier by starting your pyrethrum indoors.

Last Frost Date

In Manassas the average date of last frost happens on April 15. You should expect an average low temperature of 0°F in the coldest months of winter.

Keep in mind that USDA zone info for Manassas is not always accurate and the actual date of last frost will vary from year to year. Half of the time in Manassas you get a frost after April 15 so just be sure to be ready to protect your pyrethrum if you have one of those late frosts.

USDA Zone Info for Manassas

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 Manassas

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