The USDA Zone info is a great tool for gardeners to help us estimate 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 Port Townsend you can estimate when it's the best time to plant flower-of-an-hour by reviewing 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.

Flower-of-an-Hour are barely cold tolerant which tells us 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 Port Townsend 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 fully mature. If you are starting your flower-of-an-hour indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

In Port Townsend the average date of last frost happens on March 15. It might get as low as 15°F during the coldest months of winter.

Since the USDA zone info for Port Townsend is an average the actual date of last frost changes from year to year. Half of the time in Port Townsend there is a last frost after March 15 so make sure that you are ready to protect your flower-of-an-hour if you have a late frost.

USDA Zone Info for Port Townsend

Here is the info for USDA Zone 8b.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	15°F
Highest Expected Low	20°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 20°F.

Plants to Grow in Port Townsend

You may be interested in your other planting guides for Port Townsend.