How to Compost Your Kitchen Waste All Year Round (Part Two)

In my previous post last week I explained how to modify a Dalek compost bin so that it can be used to make compost quickly and all year round. In my final post this week I will be revealing how to use the modified Dalek and how to get the best results from it. I am delighted to hear that allotment 201 is giving it a try.

Having filled the Dalek with soil or old compost up to the start of the insulated portion, kitchen waste materials can now be added. It is ok to include all types of fruit and veg waste including veg peelings, apple cores, banana skins, orange peel, tea bags, coffee grinds, egg shells etc. But because the bin is not rat proof, I wouldn’t put any meat, fish or cooked food in there. The other thing to avoid is paper or cardboard which can matt together forming a heavy mush which will clog up the bin and end up in a smelly mess.

The next thing to do is to prepare the waste materials. I usually wait until there is at least 2 Kg of waste before adding it to the Dalek. There are 4 things to consider – moisture, texture, nitrogen content and size. The fruit and veg waste has a very high moisture and relatively high nitrogen content so it will need to be balanced with a dryer material with a relatively high carbon content – I often use straw or hay since I can get them cheaply and they also have a hollow structure which will help trap beneficial air. Sawdust can also be used and I have even experimented with wood based cat litter (unused of course!). If you have pets such as chickens, rabbits, guinea pigs etc, then the nest clearings and droppings are excellent for this too. The veg waste is also soft and mushy so the open texture and coarse nature of the straw, hay or sawdust will help to keep the material open and allow in air. Usually a few large handfuls of the dry material are sufficient to soak up the moisture when added to a couple of Kg of waste. The kitchen waste will also need chopping up so I put it in one of those floppy builders tubs, add the dry material then use a spade to mix and chop the whole lot up in one go. A spade full of soil or old compost will help introduce beneficial composting organisms into the mixture. A light sprinkling of the QR activator solution can also be added to the tub but you can add it into the bin before adding the waste (as per the usual QR method) if you wish. I should also mention that the occasional sprinkling of lime should be added to the tub – this reduces the acidity and worms also use it to help them digest their food

The waste mixture can now be added to the Dalek making sure that it sits in a fairly even layer on the top of the material in the bin. To retain the heat put a layer or two of Hessian sacking over the compost or some straw stuffed inside an old onion sack makes an ideal duvet. Finally put the lid on the Dalek and the rainproof cover on as explained in last weeks post (part one). Adding the waste to the bin usually takes no longer than 10 minutes and is time well spent.

The first addition of material, depending on the outside air temperature, will usually take a few days to get going and heat up. Subsequent regular additions will heat up more quickly. The heat will die down after another few days so weekly additions will keep the ball rolling. At this time of year the temperature in the bin can get up to about 40C without a problem, in midsummer expect temperature up to 65C and in winter up to 30C. Of course there are many factors which will influence the temperature including thickness and type of insulation, amount of material, nitrogen content, outside temperature and weather conditions. To get more heat you can apply thicker insulation, more waste or increase the nitrogen content (the bacteria thrive on this and produce the heat through their high metabolic activity) by adding urine, nettles or manure (chicken poo is excellent!). Wind-chill and rain are worst enemies for cooling the heap down so positioning the bin in a sheltered position can be beneficial.

'The resulting compost will be like vermicompost from a worm bin'

Keep adding the waste on a regular basis and you will notice that it does not fill up - the material sinks down leaving an air gap around the edge allowing natural ventilation by convection to the compost. I think this is one of the clever things about the Dalek and my main reason for liking them.

After about 6 weeks or so, begin removing the soil or old compost from the bottom of the bin. You will probably be able to tunnel your way in which will improve ventilation to the compost. It is important to remove material from the whole of the base area if possible to avoid compaction which can lead to airless conditions. (This is the drawback of the Dalek in that they don’t have sufficient access to the compost around the full perimeter of the base) Over the next month or two, with regular additions of waste and regular removal of material from the base the finished compost will start to emerge.

Over a few months the populations of organisms will increase. In particular, brandling or tiger worms will thrive and form large writhing masses! The resulting compost will be like vermicompost from a worm bin and will be a bit sticky and jelly-like, but excellent stuff nonetheless and ideal for top dressing plants, giving them a real boost. Mice will probably find a home in the bin too, they also help by tunnelling through the compost making useful airways to aerate the compost.

Leaving the bin for a few weeks while you go on holiday is not a problem and I have often had a pleasant surprise when returning to find gorgeous dark compost! Once you start to harvest the compost you should be able to continue doing so on a regular basis.

Over the last 2.5 years, I have been developing a compost bin that has all the advantages of the modified Dalek with some further improvements including rat proofing, full access to the compost around its base and a flat pack design. Details and availability will be posted on my website (www.qrcompostingsolutions.co.uk) soon.

I have thoroughly enjoyed writing my posts and answering questions/comments from readers. I do hope that I get invited again to do some more posts in the future but in the meantime please feel free to leave any questions/comments at this post or on my website and I will answer them as soon as possible.

Happy Composting!

Andy

Labels: allotment-compost-bin, compost tips, compost-making

How to Compost Your Kitchen Waste All Year Round (Part One)

We have talked about making compost with the plant waste materials that come from our gardens – but what about the continuous stream of waste that comes from our kitchens all year round? In the warmer months of the year we can compost this waste with the grass clippings, hedge clippings and other garden debris that is available but during the colder months this type of heap will not heat up and it will just sit there and pile up. If not dealt with properly it can end up as a putrefying slimy mass and will probably attract rats.

The easiest solution is to use one of those plastic conical shaped compost bins, otherwise known as Daleks, which are very common place these days and are available at a discounted price from most councils. They can be easily adapted to convert kitchen waste to compost all year round.

If your soil is not free draining, it is best to dig a small pit about 4” (10cm) deep, slightly larger than the base area of the Dalek and fill it with gravel or hardcore. This will provide excellent drainage and allow excess moisture to seep away. Next, place a circle of housebricks on top of the gravel or ground ensuring that they form a level surface on which the Dalek can be safely rested. Make sure there are air gaps of at least 1” (2.5cm) between the bricks to allow air to get to the bottom of the heap. Drill some 8mm diameter holes around the rim of the lid – this will allow air to vent up through the bin and out of the lid.

Miss Bruce always used to build her compost heaps with a thin layer of charcoal in the bottom of her compost heaps. I think this is an excellent idea and one that I always follow because charcoal can absorb bad smells (charcoal is used in odoreaters!). It has also been proven that ‘biochar’ can aid soil fertility.

For all year round composting, the heat needs to be retained within the Dalek by adding a thick layer of insulation material around the upper part of the bin. This is a case of what you can get your hands on but it needs to be light, water proof and a good insulator. Several layers of old bubblewrap wrapped around the bin (above the hatch so access can be maintained to remove finished compost) to a depth of at least 4” is ideal. Secure the bubblewrap in place with some cloth ‘Gaffa’ tape (Duck tape) and/or stretch a couple of bungee cords around it. It took about 20 minutes to convert my Dalek and I admit it doesn’t look very pretty but the most important thing is that it will work and make good compost.

Add some old compost or soil into the bottom of the Dalek bringing the level up to a height which is above the top of the hatch so that when you add your kitchen waste materials they are within the insulated portion of the bin.

Make sure that rainwater can’t run down between the insulation and the bin by placing a large rainproof cover on top of the Dalek lid. Corrugated sheeting held down with bricks is good for the job.

In next weeks post I will explain the how and why of preparing the kitchen waste materials and adding them to the modified Dalek.

Labels: compost-making, quick-return-compost