One of the first steps you take when you are getting a good idea 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.

In Groton you can estimate when to plant zinnia by reviewing the USDA zone info.

Planting Calendar for Zinnia

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

It's not a good idea to plant zinnia until after the last frost has passed because they require warm weather.

The earliest that you can plant zinnia in Groton 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 fully mature. You can get started a couple of weeks earlier by starting your zinnia indoors.

Last Frost Date

In Groton the average date of last frost happens on April 15. It might get as low as -5°F during the coldest months of winter.

Always keep in mind that USDA zone info for Groton is just an average and the actual date of last frost changes from year to year. Since half of the time in Groton it frosts late in the year after April 15 be ready to cover your zinnia in the event of a late frost.

USDA Zone Info for Groton

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 Groton

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