When to Plant Cosmos in Broken Arrow, OK

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.

In Broken Arrow you can figure out 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.

Cosmos tend to make it in mild cold which means that you can plant them a bit earlier in the year than more sensitive plants.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant cosmos
Possibly ok, but a risky time to plant cosmos
Probably not a good time to plant cosmos

The earliest that you can plant cosmos in Broken Arrow 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 little bit earlier by starting your cosmos indoors.

Last Frost Date

The average date of last frost is April 15 in Broken Arrow. In the coldest months of winter you should expect an average low temperature of 0°F.

Keep in mind that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Broken Arrow and it is different every year. Since half of the time in Broken Arrow you get a frost after April 15 be ready to cover your cosmos in the event of one of those late frosts.

USDA Zone Info for Broken Arrow

Here is the info for USDA Zone 7a.

Average Date of Last Frost (spring)April 15
Average Date of First Frost (fall)October 15
Lowest Expected Low0°F
Highest Expected Low5°F

This means that on a really cold year, the coldest it will get is 0°F. On most years you should be prepared to experience lows near 5°F.

Plants to Grow in Broken Arrow

You may be interested in your other planting guides for Broken Arrow.