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.

It's possible to figure out when you can plant delphinium by reviewing the USDA zone info for Folsom.

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.

You can plant delphinium slightly earlier in the year because they are barely cold tolerant.

The earliest that you can plant delphinium in Folsom 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. 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

In Folsom 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.

Keep in mind that USDA zone info for Folsom may not be accurate from year to year and the actual date of last frost changes from year to year. Since half of the time in Folsom you get surprised by a frost after February 15 be ready to protect your delphinium if you have one of those late frosts.

USDA Zone Info for Folsom

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 Folsom

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