February … An agroecological year

February … An agroecological year

A monthly exploration of agroecological farming, folklore and nature by farm coordinator, Fern Towers

February begins with St Brigid’s day, or Imbolc in the Gaelic tradition (meaning ‘in the belly’, referring to the lambing season), marking the beginning of spring. Although we’ve had some wild weather this month, spring is certainly in the air at the farm, with snowdrops, birdsong and goat kids galore. As the world around us comes into life, it might seem peculiar that my choice of topic this month is waste. Although not very glamorous, the death and decay of waste is nonetheless the bedrock for new life. And how we make use of waste is essential to agroecological systems and our everyday lives.

The importance of waste for agroecology is twofold. Firstly, the argument that farming must be intensified further to feed the world’s growing population is often used incorrectly to undermine the potential of small-scale farming systems. As Colin Tudge notes (2016, p20), we currently produce enough food to feed 14 billion people. That’s the equivalent of 4,600 calories per person, per day. He continues that “the reason why so many people now have too little to eat has almost nothing to do with our ability to grow food. It is caused by waste, injustice, and the lack of food sovereignty”. One third of food purchased in the UK is thrown away, and 61% of this could have been eaten (Stuart, 2009). Secondly, the waste of non-food products is an incredibly important factor to minimise when running efficient farms. Tudge highlights the countless studies demonstrating how outputs (per hectare) from small mixed farms (when well run) far exceed the outputs of even the most intensive industrial monocultures – due to the intricate and high-class nature of the husbandry involved, and the attention placed on minimising waste (2016, p49). This means that any material which contains nutrients or biomass – from plant waste to manure or food scraps to cardboard – is utilised and returned into life cycles, rather than dumped at a landfill site. As the FAO (2021) neatly puts it, “waste is a human concept – it does not exist in natural ecosystems”, and we must learn to imitate nature by using up every morsel available to us.

This is not a new realisation, rather one that many have simply forgotten. After re-watching the BBC (2009) series The Victorian Farm, I was surprised to hear that even household scraps such as rags were collected and strewn over the fields in order to return nutrients to the soil, or collected by the ‘rag-and-bone’ man who would sell on waste to those who would turn it into other useful products. I was so impressed by this frugality that I started to question how I could better utilise waste on the farm to improve yields and reduce the need for external inputs. I remembered a visit last summer to Hillsborough Castle, where restoration of the hot houses in which they grew pineapples in eighteenth century was under way. Yes, pineapples in Northern Ireland! Of course, this could not be powered by elaborate electric hotbeds and artificial lighting back then. So how did they do it?

The answer is the wonderfully simple idea of hotbeds. These structures were built under glass frames and filled with waste like manure, then simply left for microorganisms to work their magic and create intense amounts of heat. As we have plenty of manure on the farm, I thought I would give it a try. Using ‘technologies’ such as hotbeds is so important when growing food in climates like ours, as we must make special efforts to extend our growing season. By the time that the risk of the last frost has passed (often just a couple of weeks before the Summer Solstice), so have many long, light-filled days. So, creating artificially warm microclimates is the secret trick to utilise the sunlight now coming our way.

Hotbeds are brilliant for directly sowing into and growing heat-loving crops which need a long growing season like chillies, peppers and aubergines. They are also great for placing seed trays on to encourage early germination, negating the need to splash out on expensive equipment like heat mats or electric hotbeds. Below I will take you through the simple steps to making a hotbed yourself.

You will need:

  • Scraps of wood
  • A drill and screws
  • Manure, garden waste, vegetable scraps…anything containing biomass which will rot!
  • Something to cover it with (e.g. scraps of plastic sheets or glass)
  • A soil thermometer
  • Insulating material (optional)
  • Compost (optional)

    1) Make wooden frame. This really doesn’t need to look beautiful (see video of Charles Dowding’s [2016] hotbed below, to see how scruffy they can look!). Ideally, try to make it about 90cm tall and as wide as you can (some say that 1.8m x 1.8m is good). Admittedly, mine could have been wider, as the periphery of the bed will simply act as an insulating area, losing heat quicker than the middle. But in the interests of using whatever material was to hand and not being wasteful, this is the shape I went with! (1.8m x 90cm)

    2) Fill with 60cm of manure/waste and trample down. I used goat manure mixed with hay, but you could also use food scraps, leaf litter, scraps of tissue/newspaper, or garden waste. Manure will speed things up though. If you don’t have easy access to it, contact a local stables or farm, who always have plenty to get rid of!

    3) Water with about two full watering cans.

    4) Cover with 30cm of potting compost (this can be skipped if you have more manure instead, and don’t want to sow directly into it; again, see Charles Dowding’s video).

    5) If your bed is smaller than ideal, or in an exposed location, wrap around something to insulate it. I used horticultural cloche, but you could use scraps of cloth, straw or carpet.

    6) Cover to keep the heat in. We nailed some scrap polythene to some wood to make a lid, but you could use any scrap plastic or horticultural material weighed down with stones.

    7) Leave for a week. It will likely rocket up to a very high temperature in the first week, and so be too hot for plants. Once it has started to cool and plateau, you’re ready to go! Our bed was a steady 30˚C by week two, and so ready for popping seed trays onto. Keep the seedlings covered with the lid until they get strong, and remove later in the spring.

As a first-time hotbed maker, I was mesmerised by this process. To see the thermometer reach such a high temperature when it was barely 1˚C outside was a revelation. And as a cherry on top, by the end of the growing season when you empty your hotbed, you will have a plentiful supply of compost ready to spread over your beds for an autumn mulch. I would encourage you all to give it a go this year, and to not be put off if you don’t have the exact materials specified. Part of the joy of growing food yourself is the trial and error, learning what works for you and not taking the instruction books too seriously!


BBC, (2009). The Victorian Farm https://www.bbc.co.uk/programmes/b00gn2bl. (Available to stream on Amazon Prime)

Charles Dowding, (2016). Hotbeds, an old way to raise young plants https://www.youtube.com/watch?v=NhPh4sYCW5Q

FAO, (2021). Recycling. http://www.fao.org/agroecology/knowledge/10-elements/recycling/en

Colin Tudge, (2016). Six Steps Back to the Land: Why we need small farms and millions more farmers. Green Books.

Tristram Stuart, (2009). Waste: Uncovering the Global Food Scandal. Penguin

Leave a Reply

Your email address will not be published.