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

The USDA zone info for Mount Vernon can be used to determine when it's a good idea to plant dahlia.

Planting Calendar for Dahlia

Frost tolerance for dahlia:	Not tolerant of frost.
When to plant:	After the last frost.

Dahlia are not cold tolerant which means that you really should wait until it warms up after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant dahlia in Mount Vernon 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 dahlia and expect a good harvest is probably August. You probably don't want to wait any later than that or else your dahlia may not have a chance to grow to maturity. If you are starting your dahlia indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

The average date of last frost is April 15 in Mount Vernon. It might get as low as -10°F during the coldest months of winter.

Since the USDA zone info for Mount Vernon may not be accurate from year to year the actual date of last frost will vary from year to year. Since half of the time in Mount Vernon you get surprised by a frost after April 15 be ready to cover your dahlia if you have a late frost.

USDA Zone Info for Mount Vernon

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°F

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Mount Vernon

You may be interested in your other planting guides for Mount Vernon.