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

The USDA zone info for Altoona should be looked at to estimate when you can 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 start planting them earlier than more sensitive plants.

The earliest that you can plant flax in Altoona 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. If you wait any later than that and your flax may not have a chance to grow to maturity. You can get started a little bit earlier by starting your flax indoors.

Last Frost Date

On average all chance of frost has passed is on May 15 in Altoona. You should expect an average low temperature of -25°F in the coldest months of winter.

Since the USDA zone info for Altoona is an average the actual date of last frost is different every year. Since half of the time in Altoona you get a frost after May 15 be ready to cover your flax in the event of a late frost.

USDA Zone Info for Altoona

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 Altoona

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