Bark mulch

KeenOnGreen

I am sure this has been asked before somewhere here.  We have just cleared almost all of the plants in one of our beds, except for a Clematis and two Acers, which has mostly bare soil now.  We would like to mulch the bare soil with bark chippings.

I have heard that the chippings leach nitrogen from the soil, to the detriment of plants.  If we leave the soil below the canopy of the Acers free of bark chippings, and leave half a foot or so around the Clematis, should this avoid that problem?

Hostafan1

IMHO, it's an old wives tale. 
I've never seen any proper test which show that the level of nitrogen depletion is harmful to plants when it's used as a mulch. 
Some , but not much, evidence to say freshly chipped stuff can be if it's dug into the ground, but I've seen none which suggests mulching is a problem.
If you can find any evidence to the contrary , I'd be happy to see it.

Obelixx

The RHS did test this and the levels of nitrogen depletion are negligible.  If your soil is in good state and your plants are healthy there's nothing to worry about but do make sure the soil is well soaked before mulching or you will lock in dryness.

KeenOnGreen

Thanks both.  It will be fresh chippings, but we won't be digging it in, just using it as a mulch.  

Hostafan1

KeenOnGreen said:

Thanks both.  It will be fresh chippings, but we won't be digging it in, just using it as a mulch.  

I think it's one of those things repeated so often ,that folk think it must be true.

Devonian

I've done a fair amount of research and there is no evidence to prove nitrogen depletion (or if it is, it's negligible as Obelixx says). I've trialled it and have actually noticed significant soil improvement over time.

Ideally the chips should be left in a heap (turned every few weeks) to rot down a bit but they can be put on fresh, no problem. It'll help keep weeds off and looks more attractive than bare soil in my opinion!

Hostafan1

I get tens of tons of it dropped off here every year. I layer it up with grass clippings and horse poo, which I also have dropped off free.
I leave it over winter and never turn it. ( too much ) and it's perfect for mulching in spring. Lovely and dark and crumbly

KeenOnGreen

We have tonnes of chips on the paths at our allotment, and that is gradually breaking down into soil.  Eventually we will use that on the garden at home, but for now we only have access to fresh stuff.  It's not the pretty stuff you buy at the garden centre, it's quite rough and ready, but still preferable to bare (clay) soil.

It's only this bare bed that we will much with the chips.  The rest of the garden will be mulched with rotted horse manure from the allotment.  We have a small mountain of it currently rotting.

Hostafan1

KeenOnGreen said:

We have tonnes of chips on the paths at our allotment, and that is gradually breaking down into soil.  Eventually we will use that on the garden at home, but for now we only have access to fresh stuff.  It's not the pretty stuff you buy at the garden centre, it's quite rough and ready, but still preferable to bare (clay) soil.

It's only this bare bed that we will much with the chips.  The rest of the garden will be mulched with rotted horse manure from the allotment.  We have a small mountain of it currently rotting.

I'd have no hesitation on using on bare earth. 

Stevo4

I've always mulched with bark. I like Melcourt but have used Verve too. Without fail i'm told told it will ruin my beds by 'sucking out' the nitrogen. "Cock and bull" I say gleefully, "come and see my garden". Hostafan and Obelixx are quite right.