| Can Britain’s Most Hated Weed Become a Natural Fertiliser? |
| Over the past few weeks, both Suze and I have been spending rather more time than we’d like wrestling with one of Britain’s most persistent garden invaders: bindweed. Every gardener knows the feeling. You clear a border, stand back to admire your work, and a fortnight later those familiar green shoots are already winding their way through your roses, climbing your shrubs, and wrapping themselves around anything that happens to be standing upright. For most people, bindweed has only one destination – the green waste bag. But while pulling yet another armful from a client’s garden recently, I found myself wondering whether we had become so focused on getting rid of it that we’d forgotten to ask a rather obvious question. Is bindweed actually useless? Or have we been throwing away something that nature has already spent months creating? Nature Rarely Produces Waste One of the lessons gardening teaches you over the years is that nature is astonishingly efficient. There is very little in a woodland, meadow or hedgerow that exists without purpose. Every plant occupies a niche. Every root feeds something. Every flower has evolved to attract a pollinator or disperse its seed. Bindweed is no exception. Its reputation has been earned honestly. It is aggressive, persistent, capable of regenerating from surprisingly small fragments of root, and perfectly happy to smother cherished garden plants if left unchecked. In a cultivated border it is undoubtedly a weed because it is growing somewhere we do not want it. But outside the garden gate it becomes something rather different. Its white trumpet flowers provide nectar for bees, hoverflies, butterflies and moths throughout much of the summer. The foliage supports a variety of insects, including the caterpillars of the beautiful convolvulus hawk-moth. Beneath the surface, its extensive root system helps stabilise disturbed soils and quickly recolonises bare ground following cultivation or natural disturbance. None of that makes it welcome in my clients’ borders. It does, however, remind us that weeds and worthless are not the same thing. A Remarkable Survivor If bindweed has one characteristic above all others, it is resilience. The underground roots can travel astonishing distances, often extending several metres horizontally while penetrating deeply into the soil profile. Remove the top growth and the roots send up fresh shoots. Break a section of root during digging, and that fragment may produce an entirely new plant. It is precisely this determination that frustrates gardeners. Ironically, those same characteristics also mean the plant stores a considerable quantity of nutrients and energy within its stems and foliage throughout the growing season. Every time we remove armfuls of fresh growth, we carry away nitrogen, potassium, calcium, magnesium and numerous trace elements that the plant has extracted from the soil. The question therefore becomes… Why not recover some of those nutrients ourselves? Turning a Problem into Plant Food For centuries, gardeners have produced liquid feeds from nettles and comfrey. Both are excellent because they accumulate minerals while producing large amounts of leafy growth. When allowed to decompose in water, those nutrients dissolve into the liquid and can be returned to the garden as a natural fertiliser. Although bindweed has never enjoyed the reputation of nettles or comfrey, the same principle applies. It is a vigorous plant that accumulates nutrients quickly, making it perfectly capable of producing a useful liquid feed once safely decomposed. In fact, many experienced gardeners have quietly been doing exactly that for years. Rather than risking live roots surviving in a cool compost heap, they immerse freshly removed bindweed completely underwater in a sealed container. Over several weeks, the plant material breaks down into a dark, nutrient-rich liquid that can then be diluted before application to the soil. Gardeners have increasingly revisited this approach as a practical way to recycle troublesome weeds while avoiding the risk of spreading living fragments. It is important to understand what this liquid actually is. Unlike a scientifically produced compost tea, which is brewed from mature compost to encourage beneficial microbial populations under carefully controlled conditions, a weed tea is primarily a nutrient extraction created through decomposition. It returns soluble minerals and organic compounds to the garden rather than introducing large populations of beneficial microorganisms. That distinction matters. One is principally about biology. The other is principally about recycling nutrients. Both have their place. What Does Bindweed Tea Actually Feed? Once diluted and applied to the soil, bindweed tea acts as a gentle organic liquid feed rather than a miracle fertiliser. As the bindweed decomposes, many of the nutrients it extracted during its rapid growth dissolve into the water. These include nitrogen, which supports healthy leafy growth; potassium, which contributes to flowering and overall plant vigour; calcium and magnesium, which play important roles in plant development; together with a range of trace minerals. The precise nutrient balance will naturally vary depending upon the soil in which the bindweed originally grew. Still, the resulting liquid provides a useful tonic for established ornamental plants, shrubs and trees. Perhaps more importantly, using bindweed in this way keeps those nutrients cycling within the garden rather than sending them away with the green waste collection. In effect, the weed gives back some of what it has taken from the soil. Like nettle or comfrey tea, it is best viewed as a supplementary feed rather than a complete fertiliser programme. Healthy soil still depends upon compost, organic matter and good cultivation, but bindweed tea can play a valuable supporting role as part of a wider approach to soil health. How I Would Make It If you’re tempted to give bindweed a second life, the process is refreshingly straightforward. Fill a bucket or dustbin with freshly pulled bindweed, including the stems and leaves. Cover everything completely with water, then place a heavy brick or stone on top to prevent plant material from floating to the surface. Fit a lid and leave the container somewhere well away from the patio. The smell, to put it politely, develops character. After four to eight weeks, depending upon temperature, the plant material will have broken down into a dark brown liquid. After several weeks of complete submersion, there should be no viable green growth remaining. However, many gardeners prefer to leave the mixture for six to eight weeks to maximise decomposition before use. Before using it, dilute the liquid generously. A ratio of one part weed tea to ten or twenty parts water is usually sufficient for watering around established ornamental plants, shrubs and trees. I would avoid applying it directly to edible leaves that are about to be harvested, given the nature of the fermentation process. A Word of Caution This is one occasion where shortcuts are not your friend. Never place fresh bindweed directly into a cool compost heap unless you are absolutely confident that your compost regularly reaches temperatures high enough to destroy roots and seeds. Many domestic compost heaps never achieve consistently high temperatures, allowing viable fragments to survive and emerge elsewhere in the garden. Likewise, never partially spread decomposed bindweed around the garden. If in doubt, leave it submerged for longer. Patience is considerably easier than removing another generation of bindweed next spring. Looking at Weeds Differently One of the things I enjoy most about gardening is that it constantly encourages us to question assumptions. A weed is simply a plant growing where we do not want it. That does not automatically make it valueless. Bindweed will never become my favourite plant. Suze and I will almost certainly spend many more summers pulling it from clients’ borders, teasing roots from beneath shrubs and wondering how on earth it managed to grow another metre while we weren’t looking. There may be some satisfaction in giving it one final task before it leaves the garden. Instead of sending every stem away as waste, we can allow it to return a little of what it has taken from the soil. Nature wastes very little. Perhaps gardeners shouldn’t either. |
| About our writing & imagery Many of our articles are written by us, drawing on our real-life experiences, reflections, and practical work in gardens and places we know. Some pieces are developed with the assistance of AI, used as drafting and research tools rather than as a voice or authority. Featured images may include our own photography, original AI-generated imagery, or—where noted—images kindly shared by other creators and credited accordingly (for example, via Pixabay). All content is shaped, edited, and published by Earthly Comforts, and the views expressed are our own. |
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