When to Plant Garden Mums in Portland, ME

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 a good idea to estimate when it's a good idea to plant garden mums by checking out the USDA zone info for Portland.


Planting Calendar for Garden Mums

Frost tolerance for garden mums: Tolerant of some frost.
When to plant: Up to 5 weeks before last frost.

Garden Mums are one of those plants that can tolerate a little bit of cold weather which means that you can start planting them earlier than other frost tender plants.

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

The earliest that you can plant garden mums in Portland is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant garden mums and expect a good harvest is probably September. Any later than that and your garden mums may not have a chance to fully mature. If you are starting your garden mums indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

In Portland the average date of last frost happens on April 15. You can expect an average low temperature of -15°F in the coldest months of winter.

Keep in mind that USDA zone info for Portland is an average and the actual date of last frost changes from year to year. Since half of the time in Portland you get surprised by a frost after April 15 be ready to cover your garden mums if you have one of those late frosts.

USDA Zone Info for Portland

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 Portland

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