One of the first steps you take when you are estimating your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

One way of getting a good idea when it's the best time to plant flower-of-an-hour is to refer to the USDA zone info for The Dalles.

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 barely cold tolerant.

The earliest that you can plant flower-of-an-hour in The Dalles 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. 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. If you are starting your flower-of-an-hour indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

The average date of last frost is March 15 in The Dalles. In the coldest months of winter you should expect an average low temperature of 10°F.

Since the USDA zone info for The Dalles is just an average the actual date of last frost can change quite a bit from year to year. Half of the time in The Dalles there is a last frost after March 15 so make sure that you are ready to cover your flower-of-an-hour if you have one of those late frosts.

USDA Zone Info for The Dalles

Here is the info for USDA Zone 8a.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	10°F
Highest Expected Low	15°F

This means that on a really cold year, the coldest it will get is 10°F. On most years you should be prepared to experience lows near 15°F.

Plants to Grow in The Dalles

You may be interested in your other planting guides for The Dalles.