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

A way of figuring out when it's possible to plant delphinium is to examine the USDA zone info for Faribault.

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 a bit earlier in the year because they are barely cold tolerant.

The earliest that you can plant delphinium in Faribault is April. However, you really should wait until May 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. If you wait any later than that and your delphinium may not have a chance to grow to maturity. You can get started a little bit earlier by starting your delphinium indoors.

Last Frost Date

The average date of last frost is May 15 in Faribault. You should expect an average low temperature of -25°F in the coldest months of winter.

Remember that the actual date of last frost is an average because it is based on the USDA zone info for Faribault and it is different every year. Since half of the time in Faribault there is a last frost after May 15 be ready to cover your delphinium in the event of a late frost.

USDA Zone Info for Faribault

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°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 -20°F.

Plants to Grow in Faribault

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