Potash

[Shelley]

When using wood ash to fertilize does it make a difference if the ash is fresh or has composted for some time?

[dontknownuttin]

Wood ash? is that Fox Farm?

[Charlie]

The only thing composting wood ash does is mix it with organic material. After wood is burned to ash it is about as broken down as much as it can get.

[Soilscience]

Generally, wood ash is better if it is well mixed into the soil and given a week or two. Of course it depends on the concentration. It doesn't take much. It will raise your pH.
Potash is usually hardwood ash. It's very high in potassium (K) and is highly soluble hydroxide, KOH. Very similar to Drano, which is NaOH, sodium hydroxide. Nasty in high concentration.
Given a little time in the soil, the K cation will swap with an H cation which will make HOH, or H2O, and the soil will have less H, making it less acid. and the K cation will be available to be taken up by the plant roots.
That's the short answer.

[insomniaczzz]

Soilscience, you give so much valuable information. While my brain does compute what you say, it does not have the capability to retain. LOL