Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You should be able to estimate when it's the best time to plant heliotrope by using the USDA zone info for Urbandale.

Planting Calendar for Heliotrope

Frost tolerance for heliotrope:	Not tolerant of frost.
When to plant:	After all chance of frost has passed.

You can not plant heliotrope until after the last frost when the weather gets warmer because they require warm weather.

The earliest that you can plant heliotrope 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 heliotrope and expect a good harvest is probably August. You probably don't want to wait any later than that or else your heliotrope may not have a chance to grow to maturity. You can get started a couple of weeks earlier by starting your heliotrope indoors.

Last Frost Date

On average the last frost is on April 15 in Urbandale. You should expect an average low temperature of -20°F in the coldest months of winter.

Keep in mind that USDA zone info for Urbandale is not always accurate and the actual date of last frost changes from year to year. Half of the time in Urbandale you get a frost after April 15 so just be sure to be ready to protect your heliotrope if you have 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.