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

In Cupertino you can estimate when it's the best time to plant ageratum by looking at the USDA zone info.

Planting Calendar for Ageratum

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

Ageratum do not do well in cold weather which tells us that you must wait until it warms up after all chance of frost has passed before you can plant them.

The earliest that you can plant ageratum in Cupertino is March. However, you really should wait until April 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 really do well. You can get started a couple of weeks earlier by starting your ageratum indoors.

Last Frost Date

On average the last frost when the weather gets warmer is on February 15 in Cupertino. It might get as low as 25°F during the coldest months of winter.

Since the USDA zone info for Cupertino may not be accurate from year to year the actual date of last frost is different every year. Since half of the time in Cupertino last frost occurs after February 15 be ready to protect your ageratum in the event of a late frost.

USDA Zone Info for Cupertino

Here is the info for USDA Zone 9b.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	25°F
Highest Expected Low	30°F

This means that on a really cold year, the coldest it will get is 25°F. On most years you should be prepared to experience lows near 30°F.

Plants to Grow in Cupertino

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