The USDA Zone info is a great tool for gardeners to help us figure out 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.

You will be able to figure out when it's a good idea to plant cosmos by looking at the USDA zone info for Hamilton.

Planting Calendar for Cosmos

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

Cosmos are barely cold tolerant which tells us that you can start planting them slightly earlier than other frost tender plants.

The earliest that you can plant cosmos 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 cosmos and expect a good harvest is probably August. If you wait any later than that and your cosmos may not have a chance to grow to maturity. Starting your cosmos indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

In Hamilton the average date of last frost happens on April 15. In the coldest months of winter you can expect an average low temperature of 5°F.

Remember that USDA zone info for Hamilton is an average and the actual date of last frost can change quite a bit from year to year. Since half of the time in Hamilton it frosts late in the year after April 15 be ready to cover your cosmos in the event of a late frost.

USDA Zone Info for Hamilton

Here is the info for USDA Zone 7b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	5°F
Highest Expected Low	10°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 10°F.

Plants to Grow in Hamilton

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