One of the best tools that you have as gardeners to help us estimate 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.

In Willoughby you can figure out when 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.

You can plant pyrethrum just a bit earlier in the year because they are moderately cold tolerant.

The earliest that you can plant pyrethrum in Willoughby 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. You probably don't want to wait any later than that or else your pyrethrum may not have a chance to fully mature. You can get started a little bit earlier by starting your pyrethrum indoors.

Last Frost Date

On average the last frost has passed is on April 15 in Willoughby. It might get as low as -5°F during the coldest months of winter.

Since the USDA zone info for Willoughby is just an average the actual date of last frost is different every year. Since half of the time in Willoughby you get a frost after April 15 be ready to cover your pyrethrum in the event of a late frost.

USDA Zone Info for Willoughby

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 Willoughby

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