One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

In Highwood you can estimate when it's a good idea to plant zinnia by checking out 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 a bad idea to plant zinnia until after the last frost has passed because they are not cold tolerant.

The earliest that you can plant zinnia in Highwood 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 fully mature. Starting your zinnia indoors is a great way to get them started a few weeks earlier.

Last Frost Date

On average the last frost is on April 15 in Highwood. In the coldest months of winter you should expect an average low temperature of -15°F.

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

USDA Zone Info for Highwood

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 Highwood

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