>>> the stuff will freeze above 40 degrees because it's so saturated.

Is this is a valid excuse?!

Going back to my Physics 101 classes; the more fine particles dissolved in water - the lower the freezing temperature.

Think salt-water and/or (car) anti-freeze...

recoil rob....

Regardless of why "Foliage-Pro" freezes, thanks for sharing this information with the forum members. I use this fertilizer, and never gave storage temps. any thought. Now I know the rest of the story.

Much obliged.

Frank

It actually doesn't change phase to a solid (freeze), rather, it forms precipitants, which means that some of the ingredients fall out of solution. This occurs because when the solution is warm, solution molecules are vibrating faster, so remain farther apart, leaving more space between them for dissolved solids. As the solution cools and the space between vibrating molecules is reduced, the contraction is like squeezing a sponge. Relative humidity/dew point is a similar situation, except it's a gas and a liquid instead of a liquid and a solid. In the case of the fertilizer, the low temperature causes the solution to reach a supersaturated state and some of the dissolved solids that can no longer be held in solution precipitate.

Al

Makes sense but I never considered this. I just brought my bottle inside after reading this thread!

If its just a matter of precipitating out of solution you should be able to redissolve it with a little heat and agitation.