One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You should be able to figure out when it's possible to plant ageratum by reviewing the USDA zone info for Hamilton.

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 it's important to wait until after all chance of frost has passed before you can plant them.

The earliest that you can plant ageratum in Hamilton 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. Starting your ageratum indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

In Hamilton the average date of last frost happens on April 15. It might get as low as -15°F during the coldest months of winter.

Always keep in mind that the actual date of last frost is an average because it is based on the USDA zone info for Hamilton and it changes from year to year. Half of the time in Hamilton you get surprised by a frost after April 15 so always be ready to cover your ageratum if you have a surprise late frost.

USDA Zone Info for Hamilton

Here is the info for USDA Zone 5b.

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

Plants to Grow in Hamilton

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