The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

A common way of making a decision about when to plant rosemary is to examine the USDA zone info for Phoenix.

Planting Calendar for Rosemary

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

You can plant rosemary a lot earlier in the year because they are very cold tolerant.

The earliest that you can plant rosemary 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 rosemary and expect a good harvest is probably September. If you wait any later than that and your rosemary may not have a chance to grow to maturity. Starting your rosemary indoors is a great way to get them started a little bit 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.

It's important to remember that USDA zone info for Phoenix is not always accurate and the actual date of last frost will vary from year to year. Half of the time in Phoenix you get surprised by a frost after March 15 so be sure to be ready to cover your rosemary in the event of a 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.