One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

It's possible to determine when you can plant pyrethrum by using the USDA zone info for Princeton.

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 just a bit earlier in the year because they do well in moderate cold.

The earliest that you can plant pyrethrum in Princeton 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 grow to maturity. You can get started a little bit earlier by starting your pyrethrum indoors.

Last Frost Date

The average date of last frost is March 15 in Princeton. It might get as low as 10°F during the coldest months of winter.

Since the USDA zone info for Princeton is not always accurate the actual date of last frost is different every year. Since half of the time in Princeton you get surprised by a frost after March 15 be ready to cover your pyrethrum in the event of one of those late frosts.

USDA Zone Info for Princeton

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 Princeton

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