When to Plant Cosmos in Waynesboro, 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 Waynesboro can be figured out 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 can survive in mild cold which tells us that you can plant them just a tiny bit earlier in the year than plants that are more sensitive to 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 Waynesboro 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. You probably don't want to wait any later than that or else your cosmos may not have a chance to grow to maturity. If you are starting your cosmos indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

In Waynesboro the average date of last frost happens on April 15. It might get as low as -5°F during the coldest months of winter.

Always keep in mind that the actual date of last frost is not always accurate because it is based on the USDA zone info for Waynesboro and it changes from year to year. Half of the time in Waynesboro last frost occurs after April 15 so make sure that you are ready to cover your cosmos if you have one of those late frosts.

USDA Zone Info for Waynesboro

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 Waynesboro

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