One of the first steps you take when you are estimating your gardening schedule is find your 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 Portage can be used to estimate when 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 can survive in a bit of cold which means that you can plant them much earlier in the year than other plants that might not handle the cold.

The earliest that you can plant larkspur in Portage 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 fully mature. If you are starting your larkspur indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in Portage. It might get as low as -10°F during the coldest months of winter.

Since the USDA zone info for Portage is not always accurate the actual date of last frost is different every year. Since half of the time in Portage you get a frost after April 15 be ready to cover your larkspur if you have a surprise late frost.

USDA Zone Info for Portage

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°F

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Portage

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