One of the best tools that you have as gardeners to help us estimate your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You will be able to estimate when to plant delphinium by using the USDA zone info for Benton.

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.

You can plant delphinium slightly earlier in the year because they are barely cold tolerant.

The earliest that you can plant delphinium in Benton 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 few weeks earlier.

Last Frost Date

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

Since the USDA zone info for Benton is not always accurate the actual date of last frost changes from year to year. Half of the time in Benton there is a last frost after April 15 so just be sure to be ready to cover your delphinium if you have one of those late frosts.

USDA Zone Info for Benton

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 Benton

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