Before planting it is a good idea to find your USDA Zone info to estimate 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.

You should be able to determine when it's possible to plant zinnia by using the USDA zone info for Litchfield.

Planting Calendar for Zinnia

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

You should not plant zinnia until after all chance of frost has passed because they do not do well in cold weather.

The earliest that you can plant zinnia in Litchfield is May. However, you really should wait until June 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 couple of weeks earlier by starting your zinnia indoors.

Last Frost Date

In Litchfield the average date of last frost happens on May 15. It might get as low as -25°F during the coldest months of winter.

Just be sure to remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Litchfield and it can change quite a bit from year to year. Half of the time in Litchfield you get surprised by a frost after May 15 so make sure that you are ready to protect your zinnia in the event of a late frost.

USDA Zone Info for Litchfield

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Litchfield

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