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Chippings
I have a pile of chippings(silver birch and cedar) from trees that came down in the storm.How long should I leave them before spreading as a mulch? Thanks
Last edited: 04 March 2017 07:19:57
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I spread them round as soon as I create them (or as soon as I get round to it). I put them round shrubs
In the sticks near Peterborough
I have read that they shouldn't be spread immediately, but I have been doing for years without any problem.
They're said to remove nutrients from the soil as they break down. It's probably true but in practice the moisture retention and weed control outweighs that. and you could always add nutrients. ( I don't)
In the sticks near Peterborough
I use several tons of woodchip on the garden.
I've tried to research the whole " nutrient depletion" issue without anything conclusive being found.
To summarise my findings: mulching causes no depletion whatsoever, digging in uncomposted chips, may, I repeat MAY cause depletion of nitrogen. I've seen research which says yes it does, and others which says no.
If anyone can find a definitive answer , I'd love to see the research. In the meantime, I'll carry on mulching and adding it to compost bins.
there are so many 'wisdoms' passed down through the gardening ages. Many are totally untrue.
This is probably of them.
See also; 'You can't move paeonies' and 'wild flowers need poor soil'
In the sticks near Peterborough
Hostas need shade and agapanthus like to be " potbound"
PAH to both.
The list is endless
In the sticks near Peterborough
and very annoying, especially for novice gardeners.
Agapanthus have proven to be absolute thugs in my borders - huge spreading roots which prevented anything nearby from growing. That's why I dug them all up and now only grow them in pots - not because they like it!
As for the depletion thing, the microbes which break down woody matter require nitrogen to do so and will take it from the soil. However, unless you mix (say) sawdust well into the soil, they can only take it from the top few mm so nothing to worry about when mulching as that is always left on the surface (else it wouldn't actually be a mulch!) Judging by the amount of nitrates in our food and water, a bit of depletion might not be a bad thing..
Lots of gardening 'lore' is probably just misinterpretation. If someone find a method of consistently growing a particular plant well, they will do it again and tell others. Take a (made-up) example that adding crushed egg shells to the bottom of a hole before planting hostas makes them grow better. They do an experiment with 100 'eggshelled' hostas planted side by side with 100 'un-eggshelled'. The differences are clear and repeatable. One might assume "it works because it increases the calcium levels" when, in fact, it may simply be because it improves drainage. After a few rounds of 'chinese whispers', it becomes a 'fact' that hostas need extra calcium.
"As for the depletion thing, the microbes which break down woody matter require nitrogen to do so and will take it from the soil. "
Is there any "double blind" evidence that it does any harm to plants?