One of the first steps you take when you are making a decision about your gardening schedule is find your 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 it's the best time to plant dahlias is to consult the USDA zone info for Princeton.

Planting Calendar for Dahlias

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

You can not plant dahlias 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 dahlias in Princeton 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 dahlias and expect a good harvest is probably August. Any later than that and your dahlias may not have a chance to grow to maturity. Starting your dahlias indoors is a great way to get them started a little bit earlier.

Last Frost Date

On average the last frost has passed is on April 15 in Princeton. You should expect an average low temperature of -5°F in the coldest months of winter.

Since the USDA zone info for Princeton may not be accurate from year to year the actual date of last frost will vary from year to year. Half of the time in Princeton you get a frost after April 15 so make sure that you are prepared to cover your dahlias in the event of a surprise late frost.

USDA Zone Info for Princeton

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°F

This means that on a really cold year, the coldest it will get is -5°F. On most years you should be prepared to experience lows near 0°F.

Plants to Grow in Princeton

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