When to Plant Cosmos in Ephrata, PA

Before planting it is a good idea to find your USDA Zone info to determine 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.

The first opportunity to plant cosmos in Ephrata should be determined by using 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 are barely cold tolerant which means that you can start planting them slightly earlier than other plants that might not handle the cold.

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 Ephrata 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

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

Since the USDA zone info for Ephrata is not always accurate the actual date of last frost is different every year. Since half of the time in Ephrata 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 Ephrata

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 Ephrata

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