The USDA Zone info is a great tool for gardeners to help us estimate your gardening 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 Urbandale you will be able to figure out when you can plant sunflowers.

Planting Calendar for Sunflowers

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

It's probably a bad idea to plant sunflowers until after the last frost because they are not cold tolerant.

The earliest that you can plant sunflowers in Urbandale 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 sunflowers and expect a good harvest is probably August. Any later than that and your sunflowers may not have a chance to really do well. Starting your sunflowers indoors is a great way to get them started a little bit earlier.

Last Frost Date

In Urbandale the average date of last frost happens on April 15. It might get as low as -20°F during the coldest months of winter.

Since the USDA zone info for Urbandale is an average the actual date of last frost changes from year to year. Half of the time in Urbandale it frosts late in the year after April 15 so make sure that you are ready to protect your sunflowers in the event of a surprise late frost.

USDA Zone Info for Urbandale

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 Urbandale

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