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.

It's possible to determine when it's possible to plant pyrethrum by reviewing the USDA zone info for Henderson.

Planting Calendar for Pyrethrum

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

Since pyrethrum do well in moderate cold you can plant them a little bit earlier in the year than other plants that might not handle the cold.

The earliest that you can plant pyrethrum in Henderson is January. However, you really should wait until February if you don't want to take any chances.

The last month that you can plant pyrethrum and expect a good harvest is probably October. Any later than that and your pyrethrum may not have a chance to fully mature. Starting your pyrethrum indoors is a great way to get them started a little bit earlier.

Last Frost Date

The average date of last frost is February 15 in Henderson. You can expect an average low temperature of 20°F in the coldest months of winter.

Just be sure to remember that the actual date of last frost is an average because it is based on the USDA zone info for Henderson and it changes from year to year. Half of the time in Henderson you get surprised by a frost after February 15 so always be ready to cover your pyrethrum if you have a late frost.

USDA Zone Info for Henderson

Here is the info for USDA Zone 9a.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	20°F
Highest Expected Low	25°F

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

Plants to Grow in Henderson

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