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.

You can figure out when to plant zinnia in Ankeny by looking at 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 when the weather gets warmer because they require warm weather.

The earliest that you can plant zinnia in Ankeny 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 grow to maturity. You can get started a few weeks earlier by starting your zinnia indoors.

Last Frost Date

The average date of last frost is April 15 in Ankeny. In the coldest months of winter you can expect an average low temperature of -20°F.

Since the USDA zone info for Ankeny is not always accurate the actual date of last frost is different every year. Since half of the time in Ankeny last frost occurs after April 15 be ready to cover your zinnia in the event of one of those late frosts.

USDA Zone Info for Ankeny

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in Ankeny

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