One of the best tools that you have as gardeners to help us figure out your gardening schedule is the 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.

By checking out the USDA zone info for Costa Mesa you will be able to estimate when you can plant pyrethrum.

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 Costa Mesa 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. You probably don't want to wait any later than that or else your pyrethrum may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your pyrethrum indoors.

Last Frost Date

On average all chance of frost has passed is on January 31 in Costa Mesa. In the coldest months of winter you should expect an average low temperature of 35°F.

Just be sure to remember that USDA zone info for Costa Mesa is an average and the actual date of last frost can change quite a bit from year to year. Half of the time in Costa Mesa there is a last frost after January 31 so make sure that you are prepared to cover your pyrethrum if you have a surprise late frost.

USDA Zone Info for Costa Mesa

Here is the info for USDA Zone 10b.

Average Date of Last Frost (spring)	January 31
Average Date of First Frost (fall)	December 15
Lowest Expected Low	35°F
Highest Expected Low	40°F

This means that on a really cold year, the coldest it will get is 35°F. On most years you should be prepared to experience lows near 40°F.

Plants to Grow in Costa Mesa

You may be interested in your other planting guides for Costa Mesa.