Crushed grain shelf life.

It's fine.

I've had crushed grain in a bucket with a lid, and a bag with a twist tie sit for almost 2 months. Grain was fine, the beer was just as expected.

 

I've seen numbers all over the place, but not seen anyone complain that it had gone stale. You'll be just fine.

 

If kept dry and pest free, it will be fine for months.

 

Briess Malting Company states that crushed grain can be good up to 6 months.

This is from a Briess Spec Sheet:

“STORAGE AND SHELF LIFE
Store in a temperate, low humidity, pest free environment at temperatures of <90 ºF. Improperly stored malts are prone to loss of freshness and flavor. Whole kernel diastatic and preground malts are best when used within 6 months from date of manufacture. Whole kernel roasted malts may begin experiencing a slight flavor loss after 18 months.”

Cheers!

 

I have kept crushed grain in a sealed bag or container in the basement waiting for a brew day for up to a couple of months, at least, with no discernible difference on the resulting beer as compared to a fresh-crushed batch.

 

I'd say you're good for a few months and can still make a tasty beer after 6 months if stored correctly.

 

I've stored for 2+ months without any issue. Storage is in a sealed plastic bag, inside a plastic storage box that seals up real good.

 

The last place grains should be stored is in the fridge, unless you're deliberately exploring the realm of mold.