Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You can estimate when you can plant delphinium in Clayton by checking out 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.

Delphinium tend to make it in a tiny bit of cold which tells us that you can plant them a bit earlier in the year than other frost tender plants.

The earliest that you can plant delphinium in Clayton 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. If you are starting your delphinium indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

The average date of last frost is February 15 in Clayton. You should expect an average low temperature of 25°F in the coldest months of winter.

Keep in mind that the actual date of last frost is an average because it is based on the USDA zone info for Clayton and it changes from year to year. Since half of the time in Clayton last frost occurs after February 15 be ready to protect your delphinium in the event of a surprise late frost.

USDA Zone Info for Clayton

Here is the info for USDA Zone 9b.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	25°F
Highest Expected Low	30°F

This means that on a really cold year, the coldest it will get is 25°F. On most years you should be prepared to experience lows near 30°F.

Plants to Grow in Clayton

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