WEEDS are a well-known, much-hated part of gardening, and there are some pernicious ones. With this year’s spells of heat and rain, they seem worse than ever, having had fantastic conditions to grow in. Thankfully, the prolific swathes of bittercress, willowherb and dandelions are easy to remove and compost. There are, however, those weeds that can’t simply be dug out and left to rot down, the notorious bindweed and equisetum being amongst them.

So what can be done to destroy pernicious weeds once they’ve been collected up? Many gardeners will try systemic herbicides, using repeated applications of chemicals in the hope of one day ridding themselves of the problem; others take to digging as much up as possible and burning them, but neither of these options are particularly environmentally friendly, and many people are beginning to look for alternatives.

Compost soups and teas have been tried with varying degrees of success, but a potential solution has come onto the scene in the last few years that claims to be able to rid us of those stubborn weeds: hot composting. Hot composting bins tend to be large, black, insulated compost bins that, once they get some heat in, can rot down just about anything within 30-60 days. I was intrigued by the idea, and as it happened, there was a spare hot composting bin available at Harlow Carr for me to work with.

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The first step was situating the compost bin in a suitably sunny location, and preferably on concrete. Then I began the process of getting some heat into it. I started with a mix of already partially rotted material from our compost pile, then added some hot water and repeated the process for about a week until I felt it was off to a good start.

During this time, I spread the word around the garden teams in the hope of gaining a constant supply of pernicious weeds to put the bin to the test. I was not disappointed! I soon had quite the collection of bindweed and equisetum to throw into the mix, and so began the real work.

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Once the pernicious weeds were in, the only way to get them to rot down was to raise the temperature, preferably upwards of 40°C, which is not the easiest task in North Yorkshire. More hot water was added, and the temperature was monitored every day, but the thing that wasn’t checked was what was at the bottom of the bin. As it turned out I needn’t have worried too much as, despite the lower temperature, what was in there was rotting down nicely. I’ve been maintaining the experiment for a couple of months now and have found the success rate with the equisetum in particular to be fantastic, everything rots down well and I no longer have to add hot water to raise the temperature, although this will likely change as the colder weather sets in.

While there has been great success with hot composting, there are issues of volume. In a large garden such as RHS Garden Harlow Carr, the bin struggles with the amount of material generated, so a larger-scale solution in the future would need to be explored, although I am pleased to say it has decreased the burning of material.

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On a domestic level, the commercially available products are still relatively expensive and therefore not a viable option for all, costing around £150. That said, I would strongly encourage gardeners to try hot composting as a solution for themselves. Try using buckets, lining pre-existing compost bins, ordinary bins, or whatever is available to you. Just give it as much sun as possible – and feed it regularly with plenty of pernicious weeds!


• Harvest any vegetables and fruit that are ready, such as sweetcorn, courgettes, and tomatoes.

• Deadhead flowering plants to keep them going; sometimes you can get yourself a second flush!

• Keeping on top of watering, particularly containers that tend to dry out in the heat – you can also add some high potash feeds to your containers weekly.