The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A common way of figuring out when it's a good idea to plant gomphrena is to refer to the USDA zone info for Hamilton.

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.

Gomphrena tend to make it in a tiny bit of cold which tells us that you can plant them slightly earlier in the year than other frost tender plants.

The earliest that you can plant gomphrena in Hamilton 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 gomphrena and expect a good harvest is probably August. You probably don't want to wait any later than that or else your gomphrena may not have a chance to really do well. Starting your gomphrena indoors is a great way to get them started a little bit earlier.

Last Frost Date

On average the last frost has passed is on April 15 in Hamilton. It might get as low as -15°F during the coldest months of winter.

Since the USDA zone info for Hamilton is just an average the actual date of last frost can change quite a bit from year to year. Since half of the time in Hamilton you get surprised by a frost after April 15 be ready to cover your gomphrena in the event of a late frost.

USDA Zone Info for Hamilton

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 Hamilton

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