I’m sure every gardener has a weed they struggle to control. For some it’s dandelions, hairy bittercress or maybe bindweed. However, the scourge of my garden is creeping wood sorrel, a vigorous, low-growing plant whose purplish, clover-like leaves are topped with bright yellow flowers in summer.

As far as weeds go, creeping wood sorrel is fairly attractive (main image), but I still don’t hesitate to evict this little trespasser as it spreads rapidly by both seeds and tiny underground bulbs. Fortunately, it’s not hard to keep on top of this weed. I simply spend five minutes a week hoicking out seedlings before they have a chance to spread.
Why are weeds a problem?
Apart from spoiling the look of our beds, borders and other displays, weeds are detrimental to ornamental plants. They compete with them for moisture, nutrients, sunlight and space, leading to weaker growth, fewer flowers and reduced yields. Some weeds also harbour pests, diseases and viruses. For example, groundsel acts as a host plant for rust disease, while apple aphids overwinter on plantain.
Weeds in borders
Prevent weeds from becoming a problem by removing them before they have a chance to set seed. Set aside a few minutes on a designated day of the week (so you don’t forget) and pull up shallow rooted annual weeds by hand or use a hoe to sever the top of the weed from its roots – do this on a hot, dry day and you can leave the weeds on the surface of the soil to wither.

Bindweed, brambles and other perennial weeds are difficult to remove by hand and are best treated with a weed killer that will kill both its foliage and roots. As weed killers don’t discriminate between weeds and ornamentals, protect neighbouring plants with sheets of cardboard before soaking the leaves of the weed. Apply accurately with a sprayer set to a narrow, jet setting.
Weeds in the lawn
Everyone wants a pristine lawn but all too often they are let down by daisies, buttercups, clover, chickweed and the like. A few here or there are easy to remove with a trowel or a ‘daisy grubber’ tool. A patch of grass that’s overrun with weeds is best treated with a ‘feed and weed’ style product – most are suitable for applying between spring and early autumn.
Dandelions use long tap-roots to anchor themselves deep in the ground. The root is fairly brittle and breaks easily, and new plants can regenerate from any bits that are left. Some gardeners use a narrow, long bladed dandelion trowel to remove them but I find the most effective way to extract dandelions is with a long handled, weed puller device.

Prevent weeds
It’s almost impossible to stop weeds popping up in your garden but there are things you can do to discourage them. They love bare patches of soil, so make sure your displays are well stocked and use ground cover plants to fill gaps at the front. Mulch beds and borders with an 8cm (3in) layer of garden compost, leafmould or composted bark to prevent weed seeds from germinating. A naked allotment plot is a magnet to pest plants. Prevent countless weed seeds germinating by covering the ground when not in use. Landscape material, plastic sheets and even bits of old carpet are ideal for spreading across the plot and can be rolled back for access.

Not all weeds are bad
It might be tempting to remove every weed you spot but pause before plucking them all out. Dandelions, clover and many more are an important source of pollen for bees and other pollinators, while bittercress, docks and stinging nettles are the main food plants for the caterpillars of several butterfly species.

Another reason to spare weeds is that some are edible. For example, the leaves of purslane, chickweed, dandelions and many others can be eaten raw in salads. If you fancy tantalising your taste buds, make sure you wash the leaves well.