The USDA Zone info is a great tool for gardeners to help us figure out 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.

You will be able to determine when it's the best time to plant larkspur by referring to the USDA zone info for River Rouge.

Planting Calendar for Larkspur

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

Larkspur do ok in a bit of cold which tells us that you can plant them earlier in the year than more sensitive plants.

The earliest that you can plant larkspur in River Rouge 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. If you wait any later than that and your larkspur may not have a chance to fully mature. Starting your larkspur indoors is a great way to get them started a few weeks earlier.

Last Frost Date

On average all chance of frost has passed is on April 15 in River Rouge. In the coldest months of winter you should expect an average low temperature of -5°F.

It's important to remember that USDA zone info for River Rouge is not always accurate and the actual date of last frost is different every year. Half of the time in River Rouge there is a last frost after April 15 so make sure that you are prepared to cover your larkspur if you have a surprise late frost.

USDA Zone Info for River Rouge

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 River Rouge

You may be interested in your other planting guides for River Rouge.