Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A way of determining when it's a good idea to plant cosmos is to look at the USDA zone info for Red Oak.

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.

Since cosmos do ok in moderate cold you can plant them a bit earlier in the year than other frost tender plants.

The earliest that you can plant cosmos in Red Oak 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. You probably don't want to wait any later than that or else your cosmos may not have a chance to grow to maturity. You can get started a little bit earlier by starting your cosmos indoors.

Last Frost Date

On average the last frost is on April 15 in Red Oak. In the coldest months of winter you can expect an average low temperature of -20°F.

Since the USDA zone info for Red Oak is just an average the actual date of last frost will vary from year to year. Since half of the time in Red Oak you get a frost after April 15 be ready to protect your cosmos in the event of a surprise late frost.

USDA Zone Info for Red Oak

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in Red Oak

You may be interested in your other planting guides for Red Oak.