The USDA Zone info is a great tool for gardeners to help us determine 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.

In Oregon you can figure out when to plant flower-of-an-hour by checking out the USDA zone info.

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.

You can plant flower-of-an-hour slightly earlier in the year because they are one of those plants that can tolerate a tiny bit of cold weather.

The earliest that you can plant flower-of-an-hour in Oregon 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. If you wait any later than that and your flower-of-an-hour may not have a chance to grow to maturity. You can get started a little bit earlier by starting your flower-of-an-hour indoors.

Last Frost Date

On average the last frost is on April 15 in Oregon. In the coldest months of winter you should expect an average low temperature of -5°F.

Since the USDA zone info for Oregon is an average the actual date of last frost is different every year. Half of the time in Oregon last frost occurs after April 15 so always be ready to cover your flower-of-an-hour if you have one of those late frosts.

USDA Zone Info for Oregon

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°F

This means that on a really cold year, the coldest it will get is -5°F. On most years you should be prepared to experience lows near 0°F.

Plants to Grow in Oregon

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