The USDA Zone info is a great tool for gardeners to help us estimate 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.

It's possible to determine when you can plant ageratum by checking out the USDA zone info for Blackfoot.

Planting Calendar for Ageratum

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

Since ageratum are not cold tolerant you must wait until after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant ageratum in Blackfoot 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. If you are starting your ageratum indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

On average the last frost is on April 15 in Blackfoot. You should expect an average low temperature of -15°F in the coldest months of winter.

Always keep in mind that USDA zone info for Blackfoot is not always accurate and the actual date of last frost is different every year. Since half of the time in Blackfoot 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 Blackfoot

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 Blackfoot

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