Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

By reviewing the USDA zone info for Jamestown you will be able to estimate when to plant zinnia.

Planting Calendar for Zinnia

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

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

The earliest that you can plant zinnia in Jamestown 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. If you wait any later than that and your zinnia may not have a chance to grow to maturity. You can get started a little bit earlier by starting your zinnia indoors.

Last Frost Date

On average all chance of frost has passed is on April 15 in Jamestown. You can expect an average low temperature of -15°F in the coldest months of winter.

Since the USDA zone info for Jamestown is just an average the actual date of last frost changes from year to year. Half of the time in Jamestown there is a last frost after April 15 so just be sure to be ready to cover your zinnia in the event of a surprise late frost.

USDA Zone Info for Jamestown

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-15°F
Highest Expected Low	-10°F

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Jamestown

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