When can I plant Ageratum in Zone 3a

Before planting it is a good idea to find our USDA Zone info to figure out our garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for our area.

You can estimate when you can plant ageratum in Zone 3a by referring to the USDA zone info.


Planting Calendar for Ageratum

Frost tolerance for ageratum: Not tolerant of frost.
When you should plant them: After all chance of frost has passed.

Since ageratum are not cold tolerant you have to wait until after all chance of frost has passed before you can plant them.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant ageratum
Possibly ok, but a risky time to plant ageratum
Probably not a good time to plant ageratum

The earliest that you can plant ageratum in Zone 3a is May. However, you really should wait until June 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. Starting your ageratum indoors is a great way to get them started a little bit earlier.

Last Frost Date

In Zone 3a the average date of last frost happens on May 15. It might get as low as -40°F during the coldest months of winter.

Remember that USDA zone info for Zone 3a is an average and our actual date of last frost is different every year. Half of the time in Zone 3a last frost occurs after May 15 so make sure that you are prepared to cover your ageratum if we have a surprise late frost.

USDA Zone Info for Zone 3a

Here is the info for USDA Zone 3a.

Average Date of Last Frost (spring)May 15
Average Date of First Frost (fall)September 15
Lowest Expected Low-40°F
Highest Expected Low-35°F

This means that on a really cold year, the coldest it will get is -40°F. On most years you should be prepared to experience lows near -35°F.

Plants to Grow in Zone 3a

You may be interested in our other planting guides for Zone 3a.