Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

A common way of getting a good idea when to plant delphinium is to use the USDA zone info for Skiatook.

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 are barely cold tolerant you can plant them a bit earlier in the year than more sensitive plants.

The earliest that you can plant delphinium in Skiatook 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. You probably don't want to wait any later than that or else your delphinium may not have a chance to grow to maturity. 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

On average the last frost is on April 15 in Skiatook. In the coldest months of winter you can expect an average low temperature of 0°F.

Always keep in mind that the actual date of last frost is just an average because it is based on the USDA zone info for Skiatook and it is different every year. Half of the time in Skiatook there is a last frost after April 15 so make sure that you are ready to cover your delphinium in the event of a surprise late frost.

USDA Zone Info for Skiatook

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 Skiatook

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