The USDA Zone info is a great tool for gardeners to help us figure out 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.

In Millbrae you can determine when it's possible to plant ageratum by referring to 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 are not cold tolerant it's necessary to wait until after the last frost has passed before you can plant them.

The earliest that you can plant ageratum in Millbrae 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. Any later than that and your ageratum may not have a chance to fully mature. Starting your ageratum indoors is a great way to get them started a few weeks earlier.

Last Frost Date

The average date of last frost is January 31 in Millbrae. In the coldest months of winter you should expect an average low temperature of 30°F.

Remember that USDA zone info for Millbrae is just an average and the actual date of last frost changes from year to year. Since half of the time in Millbrae there is a last frost after January 31 be ready to protect your ageratum if you have a late frost.

USDA Zone Info for Millbrae

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 Millbrae

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