When to Plant Sunflowers in Collegeville, PA

The USDA Zone info is a great tool for gardeners to help us figure out 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 a good idea to estimate when it's a good idea to plant sunflowers by using the USDA zone info for Collegeville.


Planting Calendar for Sunflowers

Frost tolerance for sunflowers: Not tolerant of frost.
When to plant: After the last frost when the weather gets warmer.

It's probably a bad idea to plant sunflowers until after all chance of frost has passed because they require warm weather.

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

The earliest that you can plant sunflowers in Collegeville is April. However, you really should wait until May if you don't want to take any chances.

The last month that you can plant sunflowers and expect a good harvest is probably August. You probably don't want to wait any later than that or else your sunflowers may not have a chance to really do well. If you are starting your sunflowers indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

In Collegeville the average date of last frost happens on April 15. You should expect an average low temperature of 0°F in the coldest months of winter.

Remember that the actual date of last frost is an average because it is based on the USDA zone info for Collegeville and it is different every year. Since half of the time in Collegeville there is a last frost after April 15 be ready to protect your sunflowers in the event of a late frost.

USDA Zone Info for Collegeville

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 Collegeville

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