When to Plant Sunflowers in Bethlehem, PA

One of the first steps you take when you are making a decision about your gardening schedule is find your USDA Zone info. 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 estimate when to plant sunflowers by looking at the USDA zone info for Bethlehem.


Planting Calendar for Sunflowers

Frost tolerance for sunflowers: Not tolerant of frost.
When to plant: After all chance of frost has passed.

Since sunflowers require warm weather you really should wait until after the last frost when the weather gets warmer before you can plant them.

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 Bethlehem 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. If you wait any later than that and your sunflowers may not have a chance to grow to maturity. If you are starting your sunflowers indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Bethlehem. It might get as low as -5°F during the coldest months of winter.

Just be sure to remember that USDA zone info for Bethlehem is an average and the actual date of last frost is different every year. Half of the time in Bethlehem there is a last frost after April 15 so always be ready to protect your sunflowers if you have one of those late frosts.

USDA Zone Info for Bethlehem

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 Bethlehem

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