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.

The USDA zone info for Marshfield should be looked at to figure out when it's possible 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.

Larkspur do well in cold which means that you can get them planted much earlier than other plants that might not handle the cold.

The earliest that you can plant larkspur in Marshfield is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant larkspur and expect a good harvest is probably August. Any later than that and your larkspur may not have a chance to grow to maturity. Starting your larkspur indoors is a great way to get them started a few weeks earlier.

Last Frost Date

In Marshfield the average date of last frost happens on May 15. It might get as low as -25°F during the coldest months of winter.

Keep in mind that the actual date of last frost is an average because it is based on the USDA zone info for Marshfield and it can change quite a bit from year to year. Since half of the time in Marshfield there is a last frost after May 15 be ready to protect your larkspur if you have a surprise late frost.

USDA Zone Info for Marshfield

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 Marshfield

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