When to Plant Cosmos in State College, PA

The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

It's possible to determine when it's a good idea to plant cosmos by looking at the USDA zone info for State College.


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 slightly earlier in the year 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 State College 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 grow to maturity. Starting your cosmos indoors is a great way to get them started a few weeks earlier.

Last Frost Date

In State College the average date of last frost happens on April 15. You should expect an average low temperature of -5°F in the coldest months of winter.

It's important to remember that USDA zone info for State College may not be accurate from year to year and the actual date of last frost changes from year to year. Half of the time in State College last frost occurs after April 15 so always be ready to protect your cosmos if you have a surprise late frost.

USDA Zone Info for State College

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 State College

You may be interested in your other planting guides for State College.