When can I plant Sunflowers in Zone 1b

Before planting it is a good idea to find our USDA Zone info to estimate our garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for our area.

By reviewing the USDA zone info for Zone 1b it's a good idea to estimate when to plant sunflowers.


Planting Calendar for Sunflowers

Frost tolerance for sunflowers: Not tolerant of frost.
When you should plant them: After the last frost.

Sunflowers require warm weather which tells us that it is important to wait until it warms up 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 Zone 1b is June. However, you really should wait until July if you don't want to take any chances.

The last month that you can plant sunflowers and expect a good harvest is probably July. You probably don't want to wait any later than that or else your sunflowers may not have a chance to really do well. Starting your sunflowers indoors is a great way to get them started a few weeks earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on June 15 in Zone 1b. In the coldest months of winter we should expect an average low temperature of -55°F.

Always keep in mind that our actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Zone 1b and it changes from year to year. Since half of the time in Zone 1b last frost occurs after June 15 be ready to cover your sunflowers in the event of a surprise late frost.

USDA Zone Info for Zone 1b

Here is the info for USDA Zone 1b.

Average Date of Last Frost (spring)June 15
Average Date of First Frost (fall)July 15
Lowest Expected Low-55°F
Highest Expected Low-50°F

This means that on a really cold year, the coldest it will get is -55°F. On most years you should be prepared to experience lows near -50°F.

Plants to Grow in Zone 1b

You may be interested in our other planting guides for Zone 1b.