One of the first steps you take when you are getting a good idea your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By using the USDA zone info for Hellertown it's possible to figure out when it's possible to plant sunflowers.

Planting Calendar for Sunflowers

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

You should not plant sunflowers until after the last frost when the weather gets warmer because they are not cold tolerant.

The earliest that you can plant sunflowers in Hellertown 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 few weeks earlier.

Last Frost Date

In Hellertown 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.

Since the USDA zone info for Hellertown is just an average the actual date of last frost is different every year. Since half of the time in Hellertown you get a frost after April 15 be ready to protect your sunflowers in the event of one of those late frosts.

USDA Zone Info for Hellertown

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 Low	0°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 Hellertown

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