Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The USDA zone info for Monterey should be reviewed to figure out when it's a good idea to plant ageratum.

Planting Calendar for Ageratum

Frost tolerance for ageratum:	Not tolerant of frost.
When to plant:	After the last frost when the weather gets warmer.

It's not a good idea to plant ageratum until after all chance of frost has passed because they do not do well in cold weather.

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

Last Frost Date

On average the last frost when the weather gets warmer is on January 31 in Monterey. It might get as low as 30°F during the coldest months of winter.

Since the USDA zone info for Monterey is not always accurate the actual date of last frost changes from year to year. Since half of the time in Monterey there is a last frost after January 31 be ready to cover your ageratum if you have one of those late frosts.

USDA Zone Info for Monterey

Here is the info for USDA Zone 10a.

Average Date of Last Frost (spring)	January 31
Average Date of First Frost (fall)	December 15
Lowest Expected Low	30°F
Highest Expected Low	35°F

This means that on a really cold year, the coldest it will get is 30°F. On most years you should be prepared to experience lows near 35°F.

Plants to Grow in Monterey

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