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By Nariz

Spain Es

Can somebody help me to understand the chemistry of my garden please?
We have a log fire and for 6 years have been putting all the resulting ash on the garden and around the roses - with the memory of my Dad coming home from work with a bag of woodash given to him by a colleague and delightedly packing it round his roses. Now I read on the RHS site that it's not good practice, as it turns the earth alkaline and, if used in veggie beds, could cause scab on potatoes. We live on the edge of the Picos de Europa mountains which are mainly limestone. We dig up limestone rocks and slatey shards from our garden - should we be putting ash into our earth which gets regular barraowloads of sheep manure from the compound next door? If there is a chemistry Wizard out there, please tell me like I'm a 2-year-old, because I really don't understand all the alchemy and it seems I need to!



Ask Seaburngirl - she's good on the science bit! If you pm'd her, I'm sure she'd help.

21 Oct, 2012


If you take Sprtiz's good advice, please ask Seaburngirl to put it on here as I think many of us would be interested in the answer. Good question Nariz!

21 Oct, 2012


I have PM'd as suggested. Now we wait ...................

21 Oct, 2012


Why this pm business? Nothing annoys me more than people suggesting that as an answer.

As seaburngirl is the only one qualified to give the answer I shan't bother even though I know it.

21 Oct, 2012


Here is some reading material!

Chalky Soil;

Soil Cultivation;

Soil Improvers;

Soil nutrition;


Soil preparation;

Fertilisers;(Including Wood ash)

I hope that helps!...Tg

21 Oct, 2012


I'd like to know what Seaburngirl says too - but here's a rough answer. Woodash contains, if you're lucky, a small amount of potash. The trouble is, you don't know how much it contains because various woods produce varying amounts, but it will be miniscule in ratio terms of ash/potash. Also, if the woodash pile gets wet or damp, any potash is almost immediately destroyed, so in effect, the only impact woodash makes on your soil is to increase the alkalinity. Great for onion growers, not so good in quantity in gardens. If your soil is already full of limestone, I wouldn't be adding a lot of woodash to it on a regular basis.
On the other hand, if your plants are all growing very well, without any significant problems, why change what you're doing, on the principle of 'if it ain't broke, don't fix it'.

21 Oct, 2012


Oh Scrumpygraham...get over yourself. Others aren't bothered so why should you be?

21 Oct, 2012


I'll send you a pm with my reply.

21 Oct, 2012


lot of emailing going on there scrumpy...;o))

Wheres mine? :o))

21 Oct, 2012


oh dear! The only point of the pm scrumpyg is to let me know that there is a message about the question that i might be able to help with. I am fully aware I am not the only one 'qualified' to help as there are lots of knowledgeable people on here. Bamboo and Teegee have already supplied clear responses.
If I have upset you in the past, well I wasnt aware of it and if pm's irritate you so much........

I sometimes have a knack of explaining it in a different way thats all.

Nariz as you are already on an alkaline soil [limestone] the addition of woodash wont alter the pH of the soil, unless it is much more alkaline than the soil. there will be some nutrients in the ash such as sulphates and phosphates, both essential for growth.
However I wouldnt add large amounts as it will alter the crub strucure of the soil.

But as bamboo says if everything is growing well dont worry about it. Some plants have never read the books nor RHS advice info :o)

21 Oct, 2012


here is your pm.

The only thing i'd add to your soil preparation article is the seaweed.
Seaweed meal provides nutruents but I prefer calcified seaweed, as that has the potential to improve soil structure as well as nutrients and can be used at any time of year.
Also good in home made composts.

21 Oct, 2012


That's useful additional advice scrumpyg

21 Oct, 2012


Thanks all for your clear and interesting advice.
SBG - I've often found that some plants don't seem to conform so, as you say, they haven't learnt to read yet! ;o) I think I shall continue with my regime of liberal spreading of woodash, although perhaps I'll be a little LESS liberal - cut it down by half.
As it seems to be good for promoting fruiting I shall direct more of it to the peach trees and definitely put more into the onion bed.
Scrumpyg: I've not seen Seaweed fertiliser in the very few and very under-stocked GCs here. In the villages in this region the main form of fertilisation is the natural fertiliser produced by their animals which is dug into growing ground when semi-solid, or made into a liquid and squirted over the grass fields to add nutrients for the next years' fodder. I've not even been aware of neighbours adding THEIR woodash to their soil - which is why I posted the question.
Thanks again for your helpful input folks. :o)

22 Oct, 2012

How do I say thanks?

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