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.

It's a good idea to determine when to plant gomphrena by looking at the USDA zone info for Watertown.

Planting Calendar for Gomphrena

Frost tolerance for gomphrena:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

You can plant gomphrena slightly earlier in the year because they do ok in moderate cold.

The earliest that you can plant gomphrena in Watertown is April. However, you really should wait until May if you don't want to take any chances.

The last month that you can plant gomphrena and expect a good harvest is probably August. If you wait any later than that and your gomphrena may not have a chance to really do well. You can get started a few weeks earlier by starting your gomphrena indoors.

Last Frost Date

On average the last frost when the weather gets warmer is on May 15 in Watertown. In the coldest months of winter you should expect an average low temperature of -25°F.

Since the USDA zone info for Watertown is an average the actual date of last frost can change quite a bit from year to year. Half of the time in Watertown it frosts late in the year after May 15 so make sure that you are ready to protect your gomphrena in the event of a surprise late frost.

USDA Zone Info for Watertown

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Watertown

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