When can I plant Schizanthus in Zone 4b

Before planting it is a good idea to find our USDA Zone info to determine our garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for our area.

The USDA zone info for Zone 4b should be reffered to in order to figure out when it's a good idea to plant schizanthus.


Planting Calendar for Schizanthus

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

Schizanthus are not cold tolerant which tells us that it's important to wait until it warms up after the last frost before you can plant them.

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

The earliest that you can plant schizanthus in Zone 4b 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 schizanthus and expect a good harvest is probably August. You probably don't want to wait any later than that or else your schizanthus may not have a chance to really do well. Starting your schizanthus 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 May 15 in Zone 4b. We can expect an average low temperature of -25°F in the coldest months of winter.

Since the USDA zone info for Zone 4b is an average our actual date of last frost is different every year. Since half of the time in Zone 4b it frosts late in the year after May 15 be ready to cover your schizanthus in the event of one of those late frosts.

USDA Zone Info for Zone 4b

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)May 15
Average Date of First Frost (fall)September 15
Lowest Expected Low-25°F
Highest Expected Low-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Zone 4b

You may be interested in our other planting guides for Zone 4b.