The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

You can estimate when you can plant delphinium in Hartselle 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.

Delphinium do ok in some cold which means that you can plant them just a tiny bit earlier in the year than other frost tender plants.

The earliest that you can plant delphinium in Hartselle 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. Starting your delphinium indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

On average the last frost is on April 15 in Hartselle. In the coldest months of winter you should expect an average low temperature of 5°F.

It's important to remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Hartselle and it changes from year to year. Since half of the time in Hartselle you get a frost after April 15 be ready to protect your delphinium in the event of a late frost.

USDA Zone Info for Hartselle

Here is the info for USDA Zone 7b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	5°F
Highest Expected Low	10°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 10°F.

Plants to Grow in Hartselle

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