I’ve spent two weeks in Saturday Swot Shop looking at soil. First, at the different bands of soil from surface to deep under and last week at prevalent soil types.
This week I’m looking at what gardeners add to soil. I always think of this as manure, which it is, except I confuse myself and matters by thinking it comes from the farmyard or horse stables. Whereas the dictionary definition of manure is:
‘any substance applied to land to make it more fruitful’.
And it would seem those substances are many in number, leaving plenty of room for confusion before enriching the debate by adding in fertilizers or mentioning mulches.
So why add manure to soil ?
To add structure and for some nutrient value.
Bulky organic matter dug into to clay soils will open the soil up, allowing air to better circulate. On the other spade, added to loose sandy soil it will bind particles together facilitating better moisture retention. Bulky organic matter usually refers to farmyard or horse manure or spent mushroom compost.
Compost is another term to get to grips with. Compost refers to organic matter but matter which is the result of broken down plant waste. This waste can have its origins in plants from the garden or fruit and vegetable leftovers from the kitchen. Its transformation from plant waste to garden gold usually takes place in the alchemy of a compost heap/bin.
And then there’s leafmould which is different from compost in that you specifically have to be a tree leaf to be considered for entry into this decomposing den and then your decay happens by sleight of fungi as opposed to the bashing by bacteria which is the byword of the compost heap.
As well as being dug into the soil to improve its structure all the above materials can also be used as mulch. To mulch is to cover the surface of the soil with a layer of something. Something such the materials above and you’re in organic mulch territory. Use something fashioned from plastic or polythene and you’re mulching inorganic.
Mulch of both kinds is used to stop watering evaporating from the soil,stop weed seed from germinating and in the case of organic mulch it also forms part of the no dig technique. With this technique the mulch is left lying around on the surface whilst you get on with life and the ‘not called that for nothing’ earthworm gets to work dragging all that yummy matter down into the top soil.
So apart from where the brass might be, I think I’ve now got a better idea of the nuances of muck so next week it’s on to fertilizers.
