One gardener's weed is another gardener's treasured flower. But once you are clear about what you regard as weeds, there are ecologically friendly methods of removal apart from the time-honoured practice of digging out which work well. Mulching with bark, rotted manure or a 5cm (2in) layer of gravel over weed-free soil discourages the initial growth of weeds.
The available herbicides include contact types, which act immediately killing green leaves and stems above ground, or translocated weedkillers like glyphosate which get into the system of a plant, destroying it more slowly because, in effect, the plant moves the chemicals around. Avoid those weedkillers designed for use on paths as they remain effective in the soil for some months. Spraying herbicides in a small space is quite difficult because you may not be able to be sufficiently selective. A better solution to weeds is the use of systemic herbicide in the form of gels, which cause the plant to fail over a period of weeks. This "touch- weeding" involves painting the gel directly on to a leaf, leaving the soil unaffected.
The most effective time to apply weedkiller is when the plant is in newly green growth; do this in dry weather when you do not expect rain to dilute the effect.
No matter what we do, annual weeds are always present in fertile soil. They include hairy bittercress, groundsel and chickweed which should be hoed out regularly or handweeded before they set seed, as well as nettles which should be dug out or spot-treated with systemic products made from glyphosate.
Perennial weeds are more difficult to eradicate. In the small space they compete with treasured plants for nutrients and, if left, will usually win. They include horsetail, which can have a root as long as 3m (l0ft) deep, as well as bindweed and couch grass, which regenerate from even tiny sections of creeping underground stem. Repeated digging out or drenching with glyphosate will eventually work. If using a watering can, keep it for weedkiller only: residues can be left in the can which you may subsequently water on to your favourite plants without realising.
X IS FOR XENOPHILES
If you can create a frost-free microclimate in a sunny yard, you could consider creating a jungle effect with exotic foliage plants and even some of the hardier sub-tropical species. Many such plants are large, and wide-spreading so you should bear in mind their eventual size and know if you can interfere with this by pruning or restricting their root growth - by growing them in containers, for example. Exotic plants are challenging, so if you want an exciting environment in which large leaves abound and flowers are unusual, ignore scale and be bold.
A suitable foundation planting of hardy, distinctive, large leaves might include those of the good-natured Fatsia japonica because they are tough and evergreen, yet will suggest a sub-tropical scene. Further into the light, the hardy loquat (Eriobotrya japonica), with its long, leathery- textured leaves, makes a striking sight if grown as a dense, almost mop- headed small tree. Smaller still, the tender evergreen Cuphea cyanea from South America is covered with brilliant orange tubular bellflowers for weeks through summer. Small bamboos create an oriental look but are invasive and difficult to remove, it is best to restrain them in containers. A magnificent small, shiny fan palm from southern Europe, Chamaerops humilis will instantly light up the yard but, being tender, will need to be wrapped in a horticultural fleece for winter. The knife-like foliage of yuccas and the neat Cordyline australis 'Torbay Dazzler' all live up to the exotic aim; the easily grown phormiums or the reliable Acanthus spinosus, with distinctive, sharply incised foliage, make very suitable companions.
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