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.

By reviewing the USDA zone info for Douglas it's possible to estimate when to plant flower-of-an-hour.

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.

Flower-of-an-Hour are one of those plants that can tolerate a tiny bit of cold weather which means that you can get them planted just a bit earlier than plants that are more sensitive to the cold.

The earliest that you can plant flower-of-an-hour in Douglas 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 flower-of-an-hour and expect a good harvest is probably August. You probably don't want to wait any later than that or else your flower-of-an-hour may not have a chance to fully mature. You can get started a little bit earlier by starting your flower-of-an-hour indoors.

Last Frost Date

The average date of last frost is May 15 in Douglas. It might get as low as -25°F during the coldest months of winter.

Since the USDA zone info for Douglas is an average the actual date of last frost can change quite a bit from year to year. Half of the time in Douglas you get surprised by a frost after May 15 so make sure that you are prepared to protect your flower-of-an-hour if you have a late frost.

USDA Zone Info for Douglas

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Douglas

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