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

The earliest that you can plant delphinium in Glassboro should be figured out 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 are one of those plants that can tolerate a tiny bit of cold weather which means that you can start planting them slightly earlier than other plants that might not handle the cold.

The earliest that you can plant delphinium in Glassboro 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 fully mature. If you are starting your delphinium indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in Glassboro. You should expect an average low temperature of 0°F in the coldest months of winter.

Keep in mind that USDA zone info for Glassboro is not always accurate and the actual date of last frost changes from year to year. Since half of the time in Glassboro it frosts late in the year after April 15 be ready to protect your delphinium in the event of a late frost.

USDA Zone Info for Glassboro

Here is the info for USDA Zone 7a.

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

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

Plants to Grow in Glassboro

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