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

The first chance to plant larkspur in Arvada can be estimated by referring to the USDA zone info.

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 pretty solid cold which means that you can plant them much earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant larkspur in Arvada 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

The average date of last frost is April 15 in Arvada. You should expect an average low temperature of -10°F in the coldest months of winter.

It's important to remember that USDA zone info for Arvada is an average and the actual date of last frost changes from year to year. Half of the time in Arvada you get surprised by a frost after April 15 so make sure that you are prepared to protect your larkspur if you have a surprise late frost.

USDA Zone Info for Arvada

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 Arvada

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