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.

You should be able to determine when it's a good idea to plant sunflowers by referring to the USDA zone info for Mount Washington.

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 all chance of frost has passed because they require warm weather.

The earliest that you can plant sunflowers in Mount Washington 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. You can get started a couple of weeks earlier by starting your sunflowers indoors.

Last Frost Date

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

It's important to remember that USDA zone info for Mount Washington is an average and the actual date of last frost will vary from year to year. Half of the time in Mount Washington you get a frost after April 15 so make sure that you are ready to cover your sunflowers in the event of a surprise late frost.

USDA Zone Info for Mount Washington

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 Mount Washington

You may be interested in your other planting guides for Mount Washington.