Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You should be able to determine when you can plant larkspur by looking at the USDA zone info for Waukesha.

Planting Calendar for Larkspur

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

Larkspur are one of those plants that can tolerate quite a bit of cold weather which means that you can get them planted much earlier than more sensitive plants.

The earliest that you can plant larkspur in Waukesha 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 grow to maturity. Starting your larkspur indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

In Waukesha the average date of last frost happens on April 15. In the coldest months of winter you can expect an average low temperature of -15°F.

Remember that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Waukesha and it is different every year. Since half of the time in Waukesha it frosts late in the year after April 15 be ready to cover your larkspur in the event of a late frost.

USDA Zone Info for Waukesha

Here is the info for USDA Zone 5b.

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

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Waukesha

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