One of the best tools that you have as gardeners to help us estimate 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 will be able to figure out when you can plant ageratum by referring to the USDA zone info for Salem.

Planting Calendar for Ageratum

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

Since ageratum require warm weather you have to wait until after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant ageratum in Salem 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 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

On average the last frost has passed is on April 15 in Salem. You can expect an average low temperature of 5°F in the coldest months of winter.

Keep in mind that the actual date of last frost is an average because it is based on the USDA zone info for Salem and it changes from year to year. Since half of the time in Salem last frost occurs after April 15 be ready to protect your ageratum in the event of a late frost.

USDA Zone Info for Salem

Here is the info for USDA Zone 7b.

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

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

Plants to Grow in Salem

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