One of the best tools that you have as gardeners to help us estimate 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.

It's a good idea to determine when it's the best time to plant delphinium by looking at the USDA zone info for Sullivan City.

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.

Delphinium tend to make it in very little cold which means that you can plant them just a tiny bit earlier in the year than more sensitive plants.

The earliest that you can plant delphinium in Sullivan City is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant delphinium and expect a good harvest is probably September. If you wait any later than that and 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 little bit earlier.

Last Frost Date

In Sullivan City the average date of last frost happens on February 15. In the coldest months of winter you should expect an average low temperature of 25°F.

Always keep in mind that the actual date of last frost is not always accurate because it is based on the USDA zone info for Sullivan City and it will vary from year to year. Half of the time in Sullivan City last frost occurs after February 15 so make sure that you are prepared to protect your delphinium if you have a late frost.

USDA Zone Info for Sullivan City

Here is the info for USDA Zone 9b.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	25°F
Highest Expected Low	30°F

This means that on a really cold year, the coldest it will get is 25°F. On most years you should be prepared to experience lows near 30°F.

Plants to Grow in Sullivan City

You may be interested in your other planting guides for Sullivan City.