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.

A way of making a decision about when it's possible to plant flower-of-an-hour is to refer to the USDA zone info for Chelsea.

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 do ok in moderate cold you can plant them slightly earlier in the year than other frost tender plants.

The earliest that you can plant flower-of-an-hour in Chelsea 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 really do well. 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 April 15 in Chelsea. In the coldest months of winter you should expect an average low temperature of -5°F.

Since the USDA zone info for Chelsea may not be accurate from year to year the actual date of last frost will vary from year to year. Half of the time in Chelsea it frosts late in the year after April 15 so just be sure to be ready to protect your flower-of-an-hour in the event of a surprise late frost.

USDA Zone Info for Chelsea

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 Chelsea

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