Common weeds and what to do about them – perennial weeds

1. Perennial weeds

Perennial weeds do not die at the end of growing season. They may lay dormant in the winter, but will become noticeable in the spring.

Common perennial weeds are listed below.

Couch grass
an image showing the roots and stems of couch grass
Couch grass – Elymus repens

Invasive with distinctive tough wiry white underground stems, sending up shoots to populate another part of the plot.

Control it.  Persistence is required. Dig up all the roots at least one year before planting perennial beds. Digging out a potato crop helps to clear the roots. Root fragments regrow quickly, so constant attention is needed. The roots are fairly shallow. Regular hoeing during the year will weaken it. Hoe in early spring around your perennials and for bulbs, wait till the foliage is dying back.

Suppress new invasions with mulch. Covering unused ground with cardboard and 100cms of wood chippings over winter and through spring helps.

Bindweed
image showing the large white bell shaped flowers of hedge bindweed
Hedge bindweed – Calystegia sepium

There are two  kinds:

  • hedge bindweed with very large white flowers.
Image showing small pink and white flowers of field bindweed
Field bindweed – Convolvulus arvensis
  • field bindweed – with smaller pink or white flowers.

It grows quickly and can smother anything in its way. It reproduces freely by both long-lasting seeds and buds from the deep roots which spread widely.

Control it. Persistent digging and hoeing. Use a knife to remove seedlings. In autumn and winter, after crops, dig out established plants. Root fragments will regenerate.

Marestail
image showing green stems of marestail
Marestail – Equisetum Arvense

Invasive persistent deep rooted perennial.

Can grow from stem fragments and rhizomes from neighbouring gardens. Will regrow from any small piece left behind. Patient persistence is needed. Don’t expect to kill the roots, but removing shoots regularly weakens the plant and thus reduces infestation.

Dandelion
image showing yellow flowers, leaves and roots of dandelion
Dandelion – Taraxacum officinale

Important food source for pollinators, but cut off the flower head once it closes to avoid seed dispersal. Deep tap root draws calcium, iron, and potassium from deep in the soil, so dandelion is good added to the compost heap. Remove the flower heads, as they can go to seed even after they’re picked.

Control it. Chop off the rosette or pull up young plants. Dig out the deep tap root in autumn. Remove flower head before it sets seed – the flower closes up after fertilisation, with tip of white seed head showing.

Eat it. Root tea is an ancient remedy used to improve liver function and reduce water retention. Use young leaves like rocket. Mature leaves can be added to soups and stews. Flowers are a pretty addition to mixed salads.