There is no disputing that some plants are not a welcome sight among a manicured lawn, a productive veg patch, or your favourite sports pitch. In growing and gardening, when it comes down to it sometimes there are plants that you just don’t want around.
We call these plants weeds.
What can we do when these weeds appear in our patch of land, what might it mean, and how can we learn to live with them?
What are weeds telling us?
Weeds can tell us a great deal about the environment, and if we want to better understand our gardens, community green spaces or allotments we should listen to them.
Different plants grow better in different conditions. Some like shade while others prefer to bask in sunshine. Some plants thrive in dry, sandy soil while others need wet, boggy conditions to survive.
Weeds are no exception to this and, if you have them growing in your garden, they can reveal secrets about your soil.
For example, dandelions (Taraxacum officinale) are one of many weeds that grow long, deep roots called taproots. Taproots drive down through compacted soil and access nutrients from deep below ground.
If dandelions are all that will grow, it’s possible that your soil is compacted, making it harder for shallower rooted plants to thrive. So you might need to get digging to loosen up the soil.
Weeds can reveal the pH of your soil, which is important to know when you’re choosing what plants to grow. Some plants flourish in acidic soil while others prefer alkaline soil.
Weeds like plantain (Plantago major) and sheep’s sorrel (Rumex acetosella) prefer to grow in acidic soil. Fat hen (Chenopodium album) flourishes in alkaline soil.
Weeds also indicate how well your soil retains water. A moss-covered lawn is a likely sign of poor-draining, wet ground. Creeping buttercup (Ranunculus repens) also occurs frequently on wet soil.
Understanding the soil conditions you have is the first step to planning a great growing space. Rather than working against what you’ve got, it’s worth doing the research to find plants that will thrive.
In order to grow healthy plants you need healthy soil.
According to the Soil Association, “You can’t see healthy soil – it is covered by plants. Plant roots hold soils together, reducing erosion, and allowing air to penetrate in spaces around roots. Roots also encourage healthier soil communities through plant-fungal interactions.”
Bare soil exposes important microscopic organisms to harmful sunrays and forces earthworms back down below the surface. Wind will also erode bare soil and rain will more easily wash away nutrients.
When weeds grow, they are attempting to cover bare soil quickly. This is why they appear so rapidly in ploughed fields, dug borders and fresh allotment beds. The very action of trying to remove weeds only encourages more to grow!
While weeds are covering bare patches of land, they can ‘condition’ the soil and help accumulate organic material, which makes the soil healthier.
They do this in many ways. The weeds with taproots that we mentioned earlier will mine nutrients from deep in the soil and bring them nearer the surface. Some weeds from the Fabaceae family such as clover (Triflolium) store additional nitrogen, a nutrient that plants need to photosynthesise. When the clover dies, the stored nitrogen is released, making it available to other plants and improving the soil health.
Rather than waiting for weeds to appear, you can mimic this type of behaviour by planting cover crops or green manures  on bare soil that you are preparing to grow vegetables or other plants. Many of the plants that can be used as green manures are closely related to lots of our most maligned weeds, including clovers and mustard plants.
Lots of weeds, including comfrey (Symphytum officinale), can be made into powerful liquid fertilisers by slowly rotting down the foliage in a covered container of water. The resulting comfrey tea  is full of essential nutrients and can be used as a summer feed for tomatoes, cucumbers, and hanging baskets.
Weeding to improve your mental health
Those of you who can regularly escape outside to a community garden or growing space will be familiar with that feeling of satisfaction when you have spent long hours on your knees steadily rooting out unwanted weeds.
Many gardeners consider hand weeding a form of meditation; a slow and steady concentration on the task at hand that tunes out the world around you as you get stuck in.
The added benefit of getting down among your plants while weeding by hand is the time to check the health of your plants. You’re far more likely to spot a potential problem early.
There is growing evidence that gardening is good for your mental health  and many GP’s in the UK will now consider referring patients with depression to horticultural therapy programmes delivered by charities like Thrive.
There are many reasons why gardening may improve your mental health; whether it be from the sense of purpose and achievement it can give you, or the opportunity to connect with others at a community garden that can reduce feelings of isolation or exclusion.
To mow or not to mow?
Many of us consider weeds the most troublesome when they start flowering in our manicured lawns, but with pollinators across the UK in decline, it might be time to let your lawn grow longer and allow a species-rich lawn to thrive.
You don’t have to ditch the lawn mower altogether; just set the blades to cut a little higher, you could mow a shorter pathway through to the garden shed.
UK conservation charity Plantlife have been encouraging people to “say no to the mow” for the month of May.
Plantlife’s Botanical Expert Dr Trevor Dines says, “our research shows that people really want to do their bit to help pollinators and one of the best ways to do that is to give the wildflowers in our lawns a chance to flower. It might sound wrong but by doing nothing to your lawn you will actually help nature”.
Every garden, and gardener, can benefit from leaving a patch in your green space to grow wild. It will save you time, provide habitat for birds and small mammals, and encourage pollinators to visit the other plants you are growing.