The USDA Zone info is a great tool for gardeners to help us determine 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.

One way of getting a good idea when to plant delphinium is to use the USDA zone info for Mount Holly.

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 a tiny bit of cold which tells us that you can plant them slightly earlier in the year than other plants that might not handle the cold.

The earliest that you can plant delphinium in Mount Holly 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. If you wait any later than that and your delphinium may not have a chance to really do well. Starting your delphinium indoors is a great way to get them started a little bit earlier.

Last Frost Date

The average date of last frost is April 15 in Mount Holly. You should expect an average low temperature of 5°F in the coldest months of winter.

Just be sure to remember that USDA zone info for Mount Holly is just an average and the actual date of last frost is different every year. Half of the time in Mount Holly it frosts late in the year after April 15 so just be sure to be ready to protect your delphinium if you have a surprise late frost.

USDA Zone Info for Mount Holly

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 Mount Holly

You may be interested in your other planting guides for Mount Holly.