Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The USDA zone info for Princeton should be read to determine when you can plant zinnia.

Planting Calendar for Zinnia

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

It's probably not a good idea to plant zinnia until after the last frost because they require warm 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 grow to maturity. You can get started a few weeks earlier by starting your zinnia indoors.

Last Frost Date

On average all chance of frost has passed is on March 15 in Princeton. It might get as low as 10°F during the coldest months of winter.

Just be sure to remember that USDA zone info for Princeton is an average and the actual date of last frost changes from year to year. Since half of the time in Princeton there is a last frost after March 15 be ready to cover your zinnia in the event of a surprise late frost.

USDA Zone Info for Princeton

Here is the info for USDA Zone 8a.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	10°F
Highest Expected Low	15°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 15°F.

Plants to Grow in Princeton

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