Eeyore, the much beloved if melancholy donkey in the Winnie the Pooh stories by A.A. Milne, says “Weeds are flowers too, once you get to know them.” So if weeds can be pretty to look at or useful, perhaps we should get to know them better before deciding if they’re plants in the wrong place or not. Many plants that are termed ‘weeds’ are native or naturalised species; they may have been bred and developed into the garden plant varieties that we covet; and have been useful in the past for medicinal or culinary purposes.
If we consider the possible uses of one common weed, which is also a native plant species you may get feel for the dilemma we have. The stinging nettle (urtica dioica) is native to Europe, North America, Asia and Africa and has a long history as a useful plant; to the extent that I would also classify it as a herb. The nettle has culinary uses – soup, salad, herbal tea; and was used as a woven fibre for cloth in the Bronze Age. In the garden it provides food for beneficial insects and is a compost activator. On the downside, nettles are perennial and spread by their root system, so can easily find their way out of that useful corner by the compost heap and into your flower borders. By this action, they have turned into a weed, as they’re now a plant in the wrong place.
Firstly let’s consider the lifespan of weeds, knowing the enemy is useful in getting the better of them.
Perennials are plants which live for many years; for example, bramble. They may have growth above ground all year or they may die back to an underground root system over the winter or dormant season. Perennial plants may reproduce by seed or vegetatively (by root or stem).
Bi-ennials are plants which live for two years, for example, spear thistle. In the first year the plant will grow a rosette of leaves at ground level (basal foliage clump). In the second year, the weed plant will flower, be pollinated, set seed and spread the seed, and then that individual plant will die.
Annuals are plants which live for one year only, for example, common chickweed. Each individual weed will grow from a seed, usually in spring, flower and set its own seed over the course of one year or growing season.
Ephemerals are plants which produce many generations in one year or growing season for example, groundsel. In other words these weeds do what annual weeds do but more quickly, with possibly four generations of flowering plants over the season.
So, how to deal with a weed problem? Cultural methods are a good starting point for all of these different types.
For annual and ephemeral weeds, regular hoeing or picking out whilst the plant is still small is the simplest method of keeping them in check. Left on the soil surface to wither, they can then be added to the compost heap. It is particularly important to remove them before they seed. Remember the old but very true saying: “one year’s seed is seven year’s weed”.
Catch the biennial weeds in their first year when they have foliage only, usually a clump or small mound of leaves. The same hoeing technique used for annual weeds will work for small plants. For the larger weed plants, it will be necessary to dig them out with a hand trowel.
Hand dig out perennial weeds such as dandelions to be sure of removing the deep tap root. A specialist dandelion fork can be a useful addition to your garden tool collection, particularly if dandelions have a habit of growing in your lawn a sit is less disruptive to the turf.
As for seriously difficult to eradicate perennial weed plants such as bindweed and ground elder, expect this to take a few seasons. The root systems on these go down a long way and can re-generate from a small piece. If you find that bindweed has twined around your plants, try watching our video on ‘how to remove bindweed’ .
For more tips, check out our other blogs on weeds, especially “A Weed is a plant in the wrong place” which highlights problems with two common garden plants.