One of the first steps you take when you are getting a good idea your gardening schedule is find your USDA Zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The first chance to plant ageratum in Riverdale should be figured out by reviewing 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.

Ageratum require warm weather which means that it's important to wait until it warms up after the last frost has passed before you can plant them.

The earliest that you can plant ageratum in Riverdale 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. Any later than that and your ageratum may not have a chance to grow to maturity. You can get started a little bit earlier by starting your ageratum indoors.

Last Frost Date

On average the last frost is on April 15 in Riverdale. It might get as low as -10°F during the coldest months of winter.

Since the USDA zone info for Riverdale is an average the actual date of last frost is different every year. Since half of the time in Riverdale you get a frost after April 15 be ready to cover your ageratum if you have a late frost.

USDA Zone Info for Riverdale

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°F

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Riverdale

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