One of the best tools that you have as gardeners to help us estimate 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.

The first chance to plant ageratum in Phoenix can be determined by checking out the USDA zone info.

Planting Calendar for Ageratum

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

Since ageratum require warm weather you have to wait until after all chance of frost has passed before you can plant them.

The earliest that you can plant ageratum in Phoenix 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 ageratum and expect a good harvest is probably August. You probably don't want to wait any later than that or else your ageratum may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your ageratum indoors.

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 will vary from year to year. Since half of the time in Phoenix you get surprised by a frost after March 15 be ready to cover your ageratum if you have 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.