One of the first steps you take when you are making a decision about 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.

By looking at the USDA zone info for Phoenix you will be able to determine when it's the best time to plant spearmint.

Planting Calendar for Spearmint

Frost tolerance for spearmint:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Spearmint can survive in cold weather which tells us that you can plant them a lot earlier in the year than other plants that might not handle the cold.

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

Last Frost Date

The average date of last frost is March 15 in Phoenix. It might get as low as 10°F during the coldest months of winter.

Keep in mind that USDA zone info for Phoenix is just an average and the actual date of last frost is different every year. Half of the time in Phoenix it frosts late in the year after March 15 so make sure that you are prepared to cover your spearmint if you have a surprise late frost.

USDA Zone Info for Phoenix

Here is the info for USDA Zone 8a.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	10°F
Highest Expected Low	15°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 15°F.

Plants to Grow in Phoenix

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