One of the best tools that you have as gardeners to help us determine your gardening schedule is the 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 determining when to plant delphinium is to consult the USDA zone info for Graham.

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 slightly earlier in the year than other frost tender plants.

The earliest that you can plant delphinium in Graham 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. If you are starting your delphinium indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in Graham. In the coldest months of winter you should expect an average low temperature of 5°F.

Just be sure to remember that the actual date of last frost is an average because it is based on the USDA zone info for Graham and it will vary from year to year. Since half of the time in Graham you get a frost after April 15 be ready to protect your delphinium in the event of a late frost.

USDA Zone Info for Graham

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 Graham

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