One of the first steps you take when you are getting a good idea your gardening schedule is find your USDA Zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

By referring to the USDA zone info for Smyrna it's possible to estimate when it's possible to plant delphinium.

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 just a tiny bit earlier in the year than other plants that might not handle the cold.

The earliest that you can plant delphinium in Smyrna 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

The average date of last frost is April 15 in Smyrna. It might get as low as 0°F during the coldest months of winter.

Since the USDA zone info for Smyrna may not be accurate from year to year the actual date of last frost will vary from year to year. Half of the time in Smyrna last frost occurs after April 15 so be sure to be ready to protect your delphinium in the event of a surprise late frost.

USDA Zone Info for Smyrna

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 Smyrna

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