One of the first steps you take when you are getting a good idea your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

In Sebastopol you can figure out when it's the best time to plant delphinium by referring to the USDA zone info.

Planting Calendar for Delphinium

Frost tolerance for delphinium:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

You can plant delphinium just a tiny bit earlier in the year because they are barely cold tolerant.

The earliest that you can plant delphinium in Sebastopol 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 delphinium and expect a good harvest is probably September. Any later than that and your delphinium may not have a chance to fully mature. Starting your delphinium indoors is a great way to get them started a little bit earlier.

Last Frost Date

On average the last frost has passed is on February 15 in Sebastopol. In the coldest months of winter you can expect an average low temperature of 20°F.

Remember that USDA zone info for Sebastopol may not be accurate from year to year and the actual date of last frost changes from year to year. Since half of the time in Sebastopol you get surprised by a frost after February 15 be ready to cover your delphinium in the event of a surprise late frost.

USDA Zone Info for Sebastopol

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 Sebastopol

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