One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

By using the USDA zone info for Flagstaff you should be able to determine when it's a good idea to plant bougainvillea.

Planting Calendar for Bougainvillea

Frost tolerance for bougainvillea:	Not tolerant of frost.
When to plant:	After all chance of frost has passed.

You should not plant bougainvillea until after the last frost when the weather gets warmer because they are not cold tolerant.

The earliest that you can plant bougainvillea in Flagstaff is April. However, you really should wait until May if you don't want to take any chances.

The last month that you can plant bougainvillea and expect a good harvest is probably August. If you wait any later than that and your bougainvillea may not have a chance to fully mature. If you are starting your bougainvillea 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.

Always keep in mind that the actual date of last frost is an average because it is based on the USDA zone info for Flagstaff and it is different every year. Half of the time in Flagstaff last frost occurs after April 15 so just be sure to be ready to protect your bougainvillea 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.