One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

One way of estimating when you can plant dahlia is to look at the USDA zone info for Pontiac.

Planting Calendar for Dahlia

Frost tolerance for dahlia:	Not tolerant of frost.
When to plant:	After all chance of frost has passed.

It's not a good idea to plant dahlia until after the last frost when the weather gets warmer because they do not do well in cold weather.

The earliest that you can plant dahlia in Pontiac 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. If you wait any later than that and your dahlia may not have a chance to fully mature. You can get started a couple of weeks earlier by starting your dahlia indoors.

Last Frost Date

The average date of last frost is April 15 in Pontiac. You can expect an average low temperature of -10°F in the coldest months of winter.

Since the USDA zone info for Pontiac is an average the actual date of last frost will vary from year to year. Half of the time in Pontiac you get a frost after April 15 so make sure that you are ready to cover your dahlia in the event of one of those late frosts.

USDA Zone Info for Pontiac

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 Pontiac

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