Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

One way of estimating when to plant delphinium is to examine the USDA zone info for Virginia.

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.

Since delphinium are one of those plants that can tolerate a tiny bit of cold weather you can plant them a bit earlier in the year than other plants that might not handle the cold.

The earliest that you can plant delphinium in Virginia is April. However, you really should wait until May if you don't want to take any chances.

The last month that you can plant delphinium and expect a good harvest is probably August. You probably don't want to wait any later than that or else your delphinium may not have a chance to really do well. You can get started a little bit earlier by starting your delphinium indoors.

Last Frost Date

In Virginia the average date of last frost happens on May 15. You can expect an average low temperature of -35°F in the coldest months of winter.

Since the USDA zone info for Virginia is an average the actual date of last frost can change quite a bit from year to year. Half of the time in Virginia you get surprised by a frost after May 15 so make sure that you are prepared to cover your delphinium in the event of a late frost.

USDA Zone Info for Virginia

Here is the info for USDA Zone 3b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-35°F
Highest Expected Low	-30°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 -30°F.

Plants to Grow in Virginia

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