When can I plant Zinnia in Zone 3b

One of the first steps we take when we are determining our gardening schedule is find our USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for our area.

You can estimate when it's possible to plant zinnia in Zone 3b by looking at the USDA zone info.


Planting Calendar for Zinnia

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

Since zinnia require warm weather you have to wait until after the last frost before you can plant them.

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

The earliest that you can plant zinnia in Zone 3b is May. However, you really should wait until June if you don't want to take any chances.

The last month that you can plant zinnia and expect a good harvest is probably August. Any later than that and your zinnia may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your zinnia indoors.

Last Frost Date

The average date of last frost is May 15 in Zone 3b. We should expect an average low temperature of -35°F in the coldest months of winter.

Since the USDA zone info for Zone 3b is an average our actual date of last frost can change quite a bit from year to year. Since half of the time in Zone 3b we get a frost after May 15 be ready to cover your zinnia if we have one of those late frosts.

USDA Zone Info for Zone 3b

Here is the info for USDA Zone 3b.

Average Date of Last Frost (spring)May 15
Average Date of First Frost (fall)September 15
Lowest Expected Low-35°F
Highest Expected Low-30°F

This means that on a really cold year, the coldest it will get is -35°F. On most years you should be prepared to experience lows near -30°F.

Plants to Grow in Zone 3b

You may be interested in our other planting guides for Zone 3b.