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.

In Frederick you can determine when to plant ageratum by checking out the USDA zone info.

Planting Calendar for Ageratum

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

It's a bad idea to plant ageratum until after the last frost when the weather gets warmer because they are not cold tolerant.

The earliest that you can plant ageratum in Frederick 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. If you wait any later than that and your ageratum may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your ageratum indoors.

Last Frost Date

The average date of last frost is April 15 in Frederick. You can expect an average low temperature of -15°F in the coldest months of winter.

Keep in mind that USDA zone info for Frederick is an average and the actual date of last frost can change quite a bit from year to year. Since half of the time in Frederick you get surprised by a frost after April 15 be ready to protect your ageratum in the event of one of those late frosts.

USDA Zone Info for Frederick

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 Frederick

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