The USDA Zone info is a great tool for gardeners to help us determine 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 figuring out when it's possible to plant ageratum is to look at the USDA zone info for Richmond Hill.

Planting Calendar for Ageratum

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

Since ageratum do not do well in cold weather you have to wait until after the last frost before you can plant them.

The earliest that you can plant ageratum in Richmond Hill 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 really do well. You can get started a little bit earlier by starting your ageratum indoors.

Last Frost Date

The average date of last frost is March 15 in Richmond Hill. In the coldest months of winter you should expect an average low temperature of 15°F.

Since the USDA zone info for Richmond Hill is an average the actual date of last frost can change quite a bit from year to year. Half of the time in Richmond Hill it frosts late in the year after March 15 so just be sure to be ready to protect your ageratum in the event of one of those late frosts.

USDA Zone Info for Richmond Hill

Here is the info for USDA Zone 8b.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	15°F
Highest Expected Low	20°F

This means that on a really cold year, the coldest it will get is 15°F. On most years you should be prepared to experience lows near 20°F.

Plants to Grow in Richmond Hill

You may be interested in your other planting guides for Richmond Hill.