One of the first steps you take when you are making a decision about 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.

One way of getting a good idea when it's a good idea to plant delphinium is to look at the USDA zone info for Sapulpa.

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 one of those plants that can tolerate a tiny bit of cold weather you can plant them a bit earlier in the year than other plants that might not handle the cold.

The earliest that you can plant delphinium in Sapulpa 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 grow to maturity. Starting your delphinium indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

In Sapulpa the average date of last frost happens on April 15. In the coldest months of winter you can expect an average low temperature of 0°F.

Keep in mind that USDA zone info for Sapulpa is just an average and the actual date of last frost is different every year. Since half of the time in Sapulpa there is a last frost after April 15 be ready to protect your delphinium if you have a surprise late frost.

USDA Zone Info for Sapulpa

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 Sapulpa

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