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 way of estimating when it's possible to plant ageratum is to consult the USDA zone info for Longwood.

Planting Calendar for Ageratum

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

You should not 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 Longwood 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 fully mature. If you are starting your ageratum indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

The average date of last frost is February 15 in Longwood. You should expect an average low temperature of 25°F in the coldest months of winter.

It's important to remember that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Longwood and it is different every year. Since half of the time in Longwood you get surprised by a frost after February 15 be ready to cover your ageratum in the event of one of those late frosts.

USDA Zone Info for Longwood

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 Longwood

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