When to Plant Cosmos in Donora, PA

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.

By checking out the USDA zone info for Donora it's possible to determine when it's the best time to plant cosmos.


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.

You can plant cosmos just a tiny bit earlier in the year because they are one of those plants that can tolerate a tiny bit of cold weather.

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 Donora 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. 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

The average date of last frost is April 15 in Donora. In the coldest months of winter you can expect an average low temperature of -5°F.

Always 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 Donora and it is different every year. Since half of the time in Donora you get a frost after April 15 be ready to cover your cosmos if you have one of those late frosts.

USDA Zone Info for Donora

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)April 15
Average Date of First Frost (fall)October 15
Lowest Expected Low-5°F
Highest Expected Low0°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 0°F.

Plants to Grow in Donora

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