As autumn gradually replaces an all-too-typical Scottish summer, the waste for our compost bins also changes. Our compostables can be divided into two groups: greens and browns. The greens are moist, sappy waste: grass clippings, garden weeds and raw kitchen waste. Browns are dry, woody stalks and stems or wood-based material like paper and card.
A green/brown mix is best because aerobic bacteria need damp but not soggy conditions to work efficiently and turn our waste into good compost. They work well when surplus moisture is absorbed by browns which in turn break up a potentially dense and airless green mass like grass clippings. You’ll then end up with a fine, sweet-smelling material.
Unfortunately, material from the summer garden is largely green and sappy, while autumn and winter give us the dry browns that break down very slowly. So what can we do?
Firstly, composting will continue whatever we chuck in our bins, but a good green/brown mix will speed up the composting process giving you a good supply of compost in the spring.
The smaller the individual pieces of brown material the better. With lots of little edges, fungi and bacteria will multiply and work faster. That’s why shredded or chopped up stems and canes break down more quickly than large thick ones. Provided they’re kept moist.
When cutting back the herbaceous border, small stems are easy to chop into the compost heap but even better is to lay them on the grass and run a rotary mower over them. This also adds a few grass clippings.
Milder autumns mean the grass grows for longer so there may be some grass clippings from late cuts. If so, sink a fork into the top 30cm of waste to mix it all up. A few weeks later you won’t have much green stuff though the prunings and woody stems will keep coming.

Add in raw fruit and vegetable trimmings from the kitchen and tidy away outer cabbage and other brassica leaves from the veg patch. There are also all too many hardy weeds that keep germinating and growing until the hard frosts set in. 
When you only have raw kitchen scraps to add to the dry brown material, moisten any paper and envelopes and throw in the odd handful of topsoil from the garden, but never spent compost from pots.


Plant of the week

Nasturtium ‘Tip Top Velvet’ has luscious, crimson flowers and bright green leaves. The recent sun and warmth has brought out the vibrancy of the colour and the fresh looking leaves are especially welcome as many other plants start to look tired and dull.
Plant in semi shade both to deter cabbage white butterflies from laying their eggs and to cut down on watering as nasturtiums will wilt if dry.


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