When to Plant Flax in Zone 4b

The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

By reviewing the USDA zone info for Zone 4b it's possible to figure out when it's a good idea to plant flax.


Planting Calendar for Flax

Frost tolerance for flax: Tolerant of some frost.
When to plant: Up to 5 weeks before last frost.

Flax are moderately cold tolerant which tells us that you can plant them earlier than more sensitive plants.

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

The earliest that you can plant flax in Zone 4b is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant flax and expect a good harvest is probably August. You probably don't want to wait any later than that or else your flax may not have a chance to fully mature. Starting your flax indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on May 15 in Zone 4b. It might get as low as -25°F during the coldest months of winter.

It's important to remember that the actual date of last frost is just an average because it is based on the USDA zone info for Zone 4b and it will vary from year to year. Half of the time in Zone 4b you get surprised by a frost after May 15 so make sure that you are prepared to protect your flax in the event of a late frost.

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 your other planting guides for Zone 4b.