One of the first steps you take when you are figuring out your gardening schedule is find your USDA Zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

A way of estimating when it's the best time to plant zinnia is to look at the USDA zone info for Trenton.

Planting Calendar for Zinnia

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

Since zinnia do not do well in cold weather you need to wait until after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant zinnia in Trenton 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. Any later than that and 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

The average date of last frost is April 15 in Trenton. You should expect an average low temperature of 0°F in the coldest months of winter.

Just be sure to remember that USDA zone info for Trenton may not be accurate from year to year and the actual date of last frost can change quite a bit from year to year. Since half of the time in Trenton last frost occurs after April 15 be ready to protect your zinnia if you have one of those late frosts.

USDA Zone Info for Trenton

Here is the info for USDA Zone 7a.

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

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

Plants to Grow in Trenton

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