[viettaclark]

Had a couple of big bonnies of garden waste (including branches and wooden fence) and divided the ash between the compost daleks. The ones that had loads of worms are now wormless. Does potash kill them?

[Nobbie]

I don't think it kills them, but they don't like it due to the acidic nature of the ash and go somewhere else. It's usually better to leave the ash to weather for a while before adding to the compost heap, I usually have a little pile next to the heap that I add in small amounts occasionally and my heap has loads of worms

[JayG]

Although a long time ago now, chemistry was my favourite subject at school, so forgive me for pointing out that the carbonate salts in wood ash are quite strongly alkaline.

The salts are also very soluble so leach away quite quickly if spread on the garden, so I would either keep them somewhere dry until needed as a potassium feed or add in small quantities to the compost heap to keep it sweet and avoid upsetting the worms too much. 

[tode]

Hi Vietta,
Sorry to disagree with you Nobbie, but wood ash is in fact alkaline (contains calcium, magnesium and potassium oxides) and will raise the pH of your compost. This may very well drive your worms out temporarily, but they'll be back when they feel more comfortable  

Wood ash is excellent if you have a lot of grass/green stuff in your compost: it helps prevent it turning acidic (which gives you the classic slimey mess of grass mowings), and so accelerates the composting process.
If you have a small quantity, sprinkle it directly on the compost. If you've had a jumbo bonfire, collect the ash before it gets rained on, and store somewhere, covered, to prevent the minerals being washed out.  Each time you add a lot of green to compost, sprinkle some on  (saves buying lime ! .)
It's very valuable stuff: should be treated like gold dust (well, almost   )

[JayG]

Wow! Never expected to beat the prolific Tode to an answer; glad he agrees with me!

[tode]

That's OK jayG, Dolores is sitting on my arm, so I can only type with one finger of left hand.        

[Nobbie]

Chemistry never was my favourite subject I'd better not add any woodash to my blueberries to keep the soil acid then

[tode]

Maybe not        

Where abouts are you in Herts, Nobbie ?

[Spana]

Had the fence been treated  with anything or tanalised.  OH says you should not add treated timber to bonfire if the ash is for the garden. Just wonder if your worms didn't like that.

[Trillium]

Alkalinity of fresh wood ash can burn like acid and worms are no dopes. They'll move away until the ph level settles to their liking. If you've ever dropped fresh mortar onto your skin, you'll know exactly what I mean.

[viettaclark]

That's absolutely fascinating!!! This is marvellous because chicken poo is acid!!!! Means the Ph of the compost should balance out a bit! I didn't put more than a washing up bowl full of ash in each dalek and spread it around. There's another load of garden and kitchen waste gone on already so hopefully the wrigglies will come back! Thanks for the info....I can impress my gardening mates....