One of the first steps you take when you are making a decision about your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By looking at the USDA zone info for Isanti it's possible to determine when you can 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 plant them much earlier than other frost tender plants.

The earliest that you can plant larkspur in Isanti 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. If you wait 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 couple of weeks earlier.

Last Frost Date

On average the last frost has passed is on May 15 in Isanti. In the coldest months of winter you can expect an average low temperature of -30°F.

Since the USDA zone info for Isanti is not always accurate the actual date of last frost can change quite a bit from year to year. Half of the time in Isanti you get a frost after May 15 so make sure that you are prepared to cover your larkspur in the event of a late frost.

USDA Zone Info for Isanti

Here is the info for USDA Zone 4a.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-30°F
Highest Expected Low	-25°F

This means that on a really cold year, the coldest it will get is -30°F. On most years you should be prepared to experience lows near -25°F.

Plants to Grow in Isanti

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