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.

A way of figuring out when it's a good idea to plant columbine is to look at the USDA zone info for Arvada.

Planting Calendar for Columbine

Frost tolerance for columbine:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

You can plant columbine a bit earlier in the year because they do well in moderate cold.

The earliest that you can plant columbine 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 columbine and expect a good harvest is probably September. You probably don't want to wait any later than that or else your columbine may not have a chance to really do well. You can get started a few weeks earlier by starting your columbine indoors.

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.

Since the USDA zone info for Arvada may not be accurate from year to year the actual date of last frost is different every year. Half of the time in Arvada there is a last frost after April 15 so make sure that you are ready to protect your columbine in the event of 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.