The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

By checking out the USDA zone info for Rolla you should be able to determine when it's the best time to plant larkspur.

Planting Calendar for Larkspur

Frost tolerance for larkspur:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

You can plant larkspur earlier in the year because they are one of those plants that can tolerate quite a bit of cold weather.

The earliest that you can plant larkspur in Rolla 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 larkspur and expect a good harvest is probably September. You probably don't want to wait any later than that or else your larkspur may not have a chance to grow to maturity. If you are starting your larkspur indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Rolla. It might get as low as -5°F during the coldest months of winter.

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 Rolla and it will vary from year to year. Half of the time in Rolla there is a last frost after April 15 so always be ready to protect your larkspur if you have a late frost.

USDA Zone Info for Rolla

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°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 0°F.

Plants to Grow in Rolla

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