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 determine when it's possible to plant flower-of-an-hour by reviewing the USDA zone info for Belfast.

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 Belfast 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. 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 April 15 in Belfast. You should expect an average low temperature of -15°F in the coldest months of winter.

Since the USDA zone info for Belfast may not be accurate from year to year the actual date of last frost changes from year to year. Half of the time in Belfast there is a last frost after April 15 so make sure that you are ready to cover your flower-of-an-hour in the event of a surprise late frost.

USDA Zone Info for Belfast

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-15°F
Highest Expected Low	-10°F

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

Plants to Grow in Belfast

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