One of the first steps you take when you are estimating your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A common way of making a decision about when it's possible to plant zinnia is to use the USDA zone info for Richfield.

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 all chance of frost has passed because they are not cold tolerant.

The earliest that you can plant zinnia in Richfield 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 few weeks earlier by starting your zinnia indoors.

Last Frost Date

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

Always keep in mind that USDA zone info for Richfield is an average and the actual date of last frost will vary from year to year. Half of the time in Richfield it frosts late in the year after April 15 so be sure to be ready to cover your zinnia in the event of one of those late frosts.

USDA Zone Info for Richfield

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°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 -5°F.

Plants to Grow in Richfield

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