One of the best tools that you have as gardeners to help us estimate 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 getting a good idea when it's possible to plant zinnia is to consult the USDA zone info for Princeton.

Planting Calendar for Zinnia

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

You should not plant zinnia until after the last frost because they do not do well in cold weather.

The earliest that you can plant zinnia 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 zinnia and expect a good harvest is probably August. You probably don't want to wait any later than that or else your zinnia may not have a chance to really do well. You can get started a couple of weeks earlier by starting your zinnia indoors.

Last Frost Date

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

It's important to remember that USDA zone info for Princeton is not always accurate and the actual date of last frost can change quite a bit from year to year. Half of the time in Princeton there is a last frost after April 15 so make sure that you are prepared to cover your zinnia 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.