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 Hampshire should be used to estimate 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.

Since dahlia are not cold tolerant it's important to wait until after the last frost has passed before you can plant them.

The earliest that you can plant dahlia in Hampshire 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 fully mature. You can get started a little bit earlier by starting your dahlia indoors.

Last Frost Date

The average date of last frost is April 15 in Hampshire. You can expect an average low temperature of -15°F in the coldest months of winter.

Just be sure to remember that the actual date of last frost is just an average because it is based on the USDA zone info for Hampshire and it will vary from year to year. Since half of the time in Hampshire you get surprised by a frost after April 15 be ready to protect your dahlia in the event of a late frost.

USDA Zone Info for Hampshire

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 Hampshire

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