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.

You can figure out when to plant delphinium in Deerfield by reviewing 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.

Since delphinium do ok in moderate cold you can plant them a bit earlier in the year than other frost tender plants.

The earliest that you can plant delphinium in Deerfield 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 really do well. Starting your delphinium indoors is a great way to get them started a little bit earlier.

Last Frost Date

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

Since the USDA zone info for Deerfield is just an average the actual date of last frost changes from year to year. Half of the time in Deerfield last frost occurs after April 15 so always be ready to cover your delphinium in the event of a surprise late frost.

USDA Zone Info for Deerfield

Here is the info for USDA Zone 5b.

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

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Deerfield

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