Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

In Red Oak you can determine when it's possible to plant cosmos by reviewing the USDA zone info.

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 are barely cold tolerant you can plant them slightly earlier in the year than other plants that might not handle the cold.

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. If you wait any later than that and your cosmos may not have a chance to fully mature. You can get started a couple of weeks earlier by starting your cosmos indoors.

Last Frost Date

In Red Oak the average date of last frost happens on March 15. It might get as low as 10°F during the coldest months of winter.

Since the USDA zone info for Red Oak is just an average the actual date of last frost changes from year to year. Half of the time in Red Oak it frosts late in the year after March 15 so make sure that you are prepared to cover your cosmos if you have a surprise late frost.

USDA Zone Info for Red Oak

Here is the info for USDA Zone 8a.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	10°F
Highest Expected Low	15°F

This means that on a really cold year, the coldest it will get is 10°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.