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.

A common way of determining when you can plant twinspur is to look at the USDA zone info for Flagstaff.

Planting Calendar for Twinspur

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

Since twinspur do well in moderate cold you can plant them a little earlier in the year than other plants that might not handle the cold.

The earliest that you can plant twinspur in Flagstaff 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 twinspur and expect a good harvest is probably September. If you wait any later than that and your twinspur may not have a chance to grow to maturity. If you are starting your twinspur indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

On average the last frost has passed is on April 15 in Flagstaff. You should expect an average low temperature of -10°F in the coldest months of winter.

Keep in mind that USDA zone info for Flagstaff is just an average and the actual date of last frost is different every year. Half of the time in Flagstaff there is a last frost after April 15 so be sure to be ready to protect your twinspur if you have a late frost.

USDA Zone Info for Flagstaff

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 Flagstaff

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