Before planting it is a good idea to find your USDA Zone info to figure out 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.

In Coralville you can estimate when to plant flax by checking out the USDA zone info.

Planting Calendar for Flax

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

You can plant flax a little bit earlier in the year because they are moderately cold tolerant.

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

The last month that you can plant flax and expect a good harvest is probably September. You probably don't want to wait any later than that or else your flax may not have a chance to grow to maturity. If you are starting your flax indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Coralville. You can expect an average low temperature of -15°F in the coldest months of winter.

Just be sure to remember that the actual date of last frost is just an average because it is based on the USDA zone info for Coralville and it will vary from year to year. Half of the time in Coralville it frosts late in the year after April 15 so be sure to be ready to protect your flax in the event of one of those late frosts.

USDA Zone Info for Coralville

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-15°F
Highest Expected Low	-10°F

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Coralville

You may be interested in your other planting guides for Coralville.