The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

It's possible to estimate when it's the best time to plant delphinium by looking at the USDA zone info for Pinckneyville.

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 do ok in moderate cold you can plant them just a tiny bit earlier in the year than more sensitive plants.

The earliest that you can plant delphinium in Pinckneyville is March. However, you really should wait until April 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. Any later than that and your delphinium may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your delphinium indoors.

Last Frost Date

The average date of last frost is April 15 in Pinckneyville. In the coldest months of winter you should expect an average low temperature of -5°F.

Keep in mind that the actual date of last frost is an average because it is based on the USDA zone info for Pinckneyville and it is different every year. Half of the time in Pinckneyville last frost occurs after April 15 so make sure that you are ready to protect your delphinium if you have a late frost.

USDA Zone Info for Pinckneyville

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°F

This means that on a really cold year, the coldest it will get is -5°F. On most years you should be prepared to experience lows near 0°F.

Plants to Grow in Pinckneyville

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