The last few days has seen a massive leaf drop here so that means it is time to make leaf mould. Collecting leaves and making that wonderful soil conditioner for next year really does mark the changing seasons.
The common advice is to use a container made from chicken wire strung around four wooden poles which are knocked into the ground. Like some many other pieces of received gardening wisdom it is not the best way. The problem is that the leaves at the edges dry out which really slows down the fungal rotting process.
Over the years I tried several different methods and found the easiest and cheapest was to use builder’s big bags, or bulk bags, that are used to deliver sand and gravel. The advantages are that they are free and stop the wind from drying out the contents.
Do not cover the top; let the rain keep the leaves wet. This is different to making ‘normal’ compost because leaf mould is a fungal process which needs to be wet.
There is no need to use any of the magic additives on the market or to add anything other than leaves. You can shred them if you wish, and that certainly speeds up the rotting process, but just plain old leaves in a big bag are all you need.
There is also a lot of discussion about how long it takes for the leaves to rot down. Some say 2-3 years but I usually get usable leaf mould in 12-18 months. It does depend on the leaves as some rot faster than others.
Now is also a good time to use leaf mould on the garden. Spread a thick layer over beds to stop winter rain compacting the soil. Do not worry if the leaves are not totally rotted as worms will help incorporation and rotting will continue so by next spring you will have a bed of wonderful soil ready for sowing carrots and other crops.
According to the Telegraph the performance of peat free composts are, to say the least, variable. A recent article reports on testing carried out by gardening Which. The conclusions are that some peat free composts are not worth buying.
The best for seeds were: “… B&Q Multipurpose, B&Q Sowing and Cutting composts and New Horizon Organic and Peat Free Growbag.” And for small plants “… B&Q Multipurpose, B&Q John Innes No.2 and Westland West + Multi Purpose Compost.”
Bits of ground up plastic coated particle board found in JAB New Horizon in 2009
I have used bags of “New Horizon” for seed sowing for many years with great success. Last year I was alarmed to find what looked like the remains of ground up kitchen units in most bags. There have been other similar reports about not so natural foreign objects in the compost. I have not found anything from the makers (William Sinclair) to explain what happened.
When growing from seed it is really essential to produce strong, vigorous plants as they are more likely to thrive and resist pests and diseases. For that you need good compost either commercial or DIY.
Some people make their own seed compost mix but to be honest the one time I tried I got severe damping off – a fungal disease that rots the stem where it enters the compost and can fell a whole tray of seedlings over night.
If you are interested then try a mix and see how it performs. Some suggestions: mature leafmould (~ 2 years old) is said to work on its own but can be mixed with sterilised (to avoid damping off) loam at a ratio of 1:1. Or garden compost, leafmould and sterilised loam at 1:1:1. [From “Encyclopaedia of Organic Gardening”, p.116, HDRA/Dorling Kindersley, 2001, ISBN 07513 33816 ]
An article on the Environmental News Network says that using compost in the garden is better that fertilizer. Adding good quality compost improves soil fertility, soil structure and provides nutrients in a way that enhances the soil.
A good quality compost can improve the soil far more than other amendments by making it more porous, and balancing the nutrients so that plants can thrive over a longer time. In clay soils … adding compost can break up clay so that water can penetrate into the earth, while losing less moisture from run-off.
A healthy soil also allows beneficial insects, earthworms and other creatures to crawl around and work the soil, which opens it up and allows more air to flow through. In turn, this aeration allows the soil to hold more water. This means that people don’t need to water their lawns and gardens as often.
Good compost is the best soil amendment but some compost is better than others. Producing quality compost is down to how it is made. Just throwing your waste material on an open heap will produce compost eventually but it will be of doubtful and variable quality. Being more systematic by waiting until you have enough materials to fill your bin in one go, having the correct mix of green (N) and brown (C) materials and the correct amount of moisture, will ensure that the compost works quickly and heats up. See the Composting pages in the Resources section above.
Every gardener should make compost from garden waste. There really is excuse for the huge bonfires that are a regular feature of most allotments. So do NOT burn fallen leaves use them to make leaf mould, see this page, which is low in nutrients but a very good soil conditioner.
And do not forget to compost your kitchen waste, be proud to have a ‘slop bucket’!
The garden has a real feel of winter now. The leaf mould is made, around 30 heaped wheel barrows of leaves were deposited in the makeshift ‘container’ by my able assistant. Not sure how well it will it will rot down but at least it prevented a neighbour from burning great piles of leaves!
Some of the beds have been cultivated, manured or had compost added depending what is to be planted next season, and then covered with their blankets. Other beds have been sown with a green manure that should over winter. The main aim is to keep the rain off to stop soil compaction and nutrient leaching.
I used two varieties of green manure this year; Hungarian grazing rye and winter tares. The rye was mostly eaten by the resident pheasants. They did not go for the tares which means I’ll be using more of that next season. The trouble is that the grazing rye does a good job of mining nutrients from the deep clay and its long roots also break up the soil. Tares fixes nitrogen, provided the whole crop is incorporated, which is useful but not required on every bed so it’s a difficult choice.
There is not much left to do now excpet a general tidy up and order the seeds for next year. Just right for these cold dark days.