One of the first steps you take when you are estimating your gardening schedule is find your USDA Zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

A common way of determining when it's the best time to plant flower-of-an-hour is to look at the USDA zone info for Sioux City.

Planting Calendar for Flower-of-an-Hour

Frost tolerance for flower-of-an-hour:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Since flower-of-an-hour are barely cold tolerant you can plant them a bit earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant flower-of-an-hour in Sioux City is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant flower-of-an-hour and expect a good harvest is probably August. Any later than that and your flower-of-an-hour may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your flower-of-an-hour indoors.

Last Frost Date

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

It's important to remember that USDA zone info for Sioux City is an average and the actual date of last frost changes from year to year. Since half of the time in Sioux City last frost occurs after April 15 be ready to protect your flower-of-an-hour if you have a surprise late frost.

USDA Zone Info for Sioux City

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 Sioux City

You may be interested in your other planting guides for Sioux City.