It’s time for the final turning over of all matters, soil.
I’ve checked my list from week one to see what’s still left to have a look at.
Words still with an air of mystery: Crumbly and Friable.
A Match of the Day sofa double act or something to do with soil structure?
A crumbly soil is one where the components which make up soil (minerals, organic matter and humus) combine in ‘crumbs’ of approximately 1-5mm in size. This is what is meant by the term ‘good crumb structure’. It’s the ideal growing soil structure as the size of the soil pieces – crumbs- are of a size to both support and surround the plant roots. If soil breaks up into crumbs of this size, it’s said to be friable.
Then there’s the earthy sounding Single Dig and 1 Spit.
A spit is the depth of a spade blade or measured, about 25- 30cm.
How far down to dig is measured using the spade blade as guide.
So single digging means digging to a depth of 1 spit and double digging… yes … to a depth of 2 spits.
And No Dig – does this mean leaving a spade in a dusty corner of the shed?
Only after putting in the ‘spade work’ although opinions seem to vary about how much of this should take place.
So in differing places along a scale; No- Dig involves digging upfront, getting rid of perennial weeds and incorporating in lots of organic matter to make a really good quality, deep bed. Once this is achieved, and this is the part that seems to be at the heart of No Dig, the soil structure will maintain itself and new matter is incorporated by the annual application of a 3-5cm mulch, which the worms incorporate down into the soil.
And Green Manures
The manures we looked at in week 3 are materials brought in from elsewhere and incorporated into the soil.
A green manure is different. It’s a plant grown directly into the soil with the intention of using it, in situ, as manure. The green manure plant is grown and then, a few weeks prior to the planting of the intended vegetable crop, the green manure is dug down into the soil, changing status from plant to manure, something it needs to do in a shortish period of time to be of benefit to the incoming plant.
Green Manures are often planted in autumn, offering protection to the soil through the winter, and then dug in to improve it, come spring.
Photo by thisisbrighteyes
