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

The USDA zone info for Lewiston can be read to figure out when to plant garden mums.

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 moderately cold tolerant which means that you can plant them earlier than other frost tender plants.

The earliest that you can plant garden mums in Lewiston 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. You probably don't want to wait any later than that or else your garden mums may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your garden mums indoors.

Last Frost Date

In Lewiston the average date of last frost happens on April 15. It might get as low as -15°F during the coldest months of winter.

Since the USDA zone info for Lewiston is an average the actual date of last frost is different every year. Since half of the time in Lewiston last frost occurs after April 15 be ready to cover your garden mums if you have a surprise late frost.

USDA Zone Info for Lewiston

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 Lewiston

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