Of course, not all weeds are to be despised and the organic gardener who gets rid of them all is wasting a valuable natural asset. Many weeds will attract insect predators, some also provide food for birds and butterflies and others, like the clovers (Trifolium sp.), can be used to fix nitro-gen in the soil. So, before making an indiscriminate onslaught on native plants, pause for thought.
Indeed, I recommend growing cultivated plants in the ornamental garden that are close to their original wild species because they will attract the same insect life.
However, I am not suggesting that you allow nature to take over, as your cultivated "foreigners" will be at the mercy of some pretty tough "locals", who will give scant regard to "entente cordiale". Most weeds must be rigorously controlled, but there are a few that should be allowed to stay if you have room. I have grouped together those which have to be removed ("Bad Weeds") and those which can be beneficial ("Good Weeds").
- The underground creepers should never be allowed to flourish or they will take over in next to no time. Amongst these be particularly ruthless with ground elder (Aegopodium podagraria),bindweed (Convolvulus arvensis), couch grass (Agropyron repens), Canada thistle (Cirsium arvense), rosebay willow-herb (Epilobium angusti-folium) and Japanese knotweed (Potygonum cuspidatum). The surface creepers like creeping buttercup (Ranunculus repens), ground ivy (Glechoma hederacea) and cinquefoil (Potentilla sp.) are slightly easier to control, but be diligent.
- Weeds that spread by seed are not difficult to control, provided they are pulled out or cut down before they-have a chance to seed. Keep an eye out for bull thistle (Cirsium vulgare) and broad -leaved willow-herb ( Epilobium montanum).
- Plants with tap roots (long, thick, fleshy roots that go straight down into the soil) like docks (Rumex sp.) and cow parsley (Anthriscus sylvestris) should be dug out.
- Storage roots (tubers, corms, bulbs or rhizomes) often break off in the soil when the plant is pulled up and this can be a means of propagation. The worst of the lot is oxalis, which-must be dealt with as soon as it shows even an exploratory leaf. Constant hoeing is the only answer. unless you can leave a sheet of black plastic in place for at least a year.
Having made sure that the real villains are banished forever, try to give room to some of the less invasive plants. As gardeners, our interest lies in the cultivation of plants for beauty and interest and for the purpose of feeding our families. How far you allow nature to take over is a matter of judgement and will depend largely on the size of your garden, and the range of wild plants you can grow will depend upon the soil, site and location. In my own garden the pretty yellow snapdragon flowers of toadflax (Linaria vulgaris) and the pure white clusters of white campion (Lychnis alba) or red campion (Lychnis dioica) are always allowed to remain. In the borders where these "weeds" have access to artificially fertile soil, they really thrive and produce flowers that rival any cultivated hybrid.
It has been said that if the dandelion (Taraxa-cum officinale) only grew in Tibet, we would be sending plant hunters to collect it and we would pay huge sums of money to nurserymen to propagate it. It may be common, but it is an undeniably pretty flower. Do not let it seed, however, or it will outstay its welcome.
The stinging nettle (Urtica dioica) is an anti-social plant, but do allow some to remain if you can because it is an extremely important food for butterflies.
- The corn poppy (Papaver rhoeas) used to be a common sight before chemical weedkillers made it virtually extinct in cornfields. It is a favourite with finches when it seeds, so it is certainly-worth growing.
Groundsel (Senecio vulgaris) and herb robert (Geranium robertianum) are valuable nectar plants for butterflies and bees, but can be a nuisance if allowed to seed.
If you have an old tree stump in the garden, you can make an attractive feature of it by covering it with ivy (Hedera hetix). Many birds and insects use ivy as a home and a food plant.
- Allow chickweed (Stellaria media) to grow in winter to help prevent the ground becoming waterlogged. It will rot down after digging in supplementing compost and manure. Do not let it grow in summer as, once it gets a hold, it can be particularly troublesome.
- The teasel (Dipsacus fullonum) is a tall, stately plant with large seed heads which attract gold-finches, who will travel far for the seeds.-The flowers attract butterflies and other insects.
Another insect attractor is lamb's quarters (Chenopodium album), which was a favourite vegetable in the Middle Ages.
Finally, there are the leguminous plants that will fix nitrogen and release it into the soil once they' are dug in. For example. the medicks (Medicaga sp.) and clovers Trifolium sp. can be allowed to remain in winter.
One of the good things about having planters is that you have less weeding to do. You will have some to do though. If you can tell the difference between the weed and the plant that you are trying to grow - pull the weed out while it is small. Planters have limited soil, nutrients, light and water. The resources that get devoured by weeds. Weeds tend to be fast growing and voracious devouring all the nutrients that your plants need to flourish.
- Add mulch to planters, containers and raised beds just as you would normally. Mulching will go a long way toward preventing weeds.
- Plant your planter to avoid weeds. Canopy plants such as hostas will not let enough light reach the soil for weeds to germinate. One of the really attractive features of planters is that you can plant more densely than you would in a garden bed because you can add nutrients and water as and when they are needed. You can move the smaller planters to catch the sun.