When to Plant Ageratum in Anchorage, AK

One of the first steps you take when you are making a decision about your gardening schedule is find your USDA Zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

In Anchorage you can determine when it's the best time to plant ageratum by reviewing the USDA zone info.


Planting Calendar for Ageratum

Frost tolerance for ageratum: Not tolerant of frost.
When to plant: After the last frost when the weather gets warmer.

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 Anchorage 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. 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 few weeks earlier.

Last Frost Date

On average the last frost has passed is on May 15 in Anchorage. It might get as low as -25°F during the coldest months of winter.

Just be sure to remember that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Anchorage and it will vary from year to year. Half of the time in Anchorage you get surprised by a frost after May 15 so just be sure to be ready to cover your ageratum if you have a late frost.

USDA Zone Info for Anchorage

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)May 15
Average Date of First Frost (fall)September 15
Lowest Expected Low-25°F
Highest Expected Low-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Anchorage

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