One of the first steps you take when you are estimating your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

One way of determining when you can plant marigold is to examine the USDA zone info for Flagstaff.

Planting Calendar for Marigold

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

It's not a good idea to plant marigold until after the last frost has passed because they require warm weather.

The earliest that you can plant marigold 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 marigold and expect a good harvest is probably August. If you wait any later than that and your marigold may not have a chance to fully mature. Starting your marigold indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

In Flagstaff the average date of last frost happens on April 15. In the coldest months of winter you should expect an average low temperature of -10°F.

Since the USDA zone info for Flagstaff is just an average the actual date of last frost can change quite a bit from year to year. Half of the time in Flagstaff last frost occurs after April 15 so make sure that you are prepared to protect your marigold 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.