A mulch is a layer of bulky organic matter, such as well rotted garden compost or manure. It is spread on the surface of the soil around plants, mainly during spring. If you don’t know much about how to maintain a garden or landscape, you can contact professional lawn maintenance specialists who can provide residential and commercial lawn maintenance services.
Why mulch? The main purpose of mulching is to keep plant roots moist and cool during summer. This they are able to do firstly by reducing surface water evaporation during warm, dry weather. This increases moisture retention. In addition, during wet weather, bulky organics absorb surplus water and hold it in reserve for the future benefit of plants. Any undue wash out of soil nutrients is halted at the same time. Surface roots are physically protected from overheating under fierce summer sun, and generally kept much cooler. Clematis, wisteria, azalea, camellia, rhododendron and pieris all need a cool root run.
Mulches also suppress weed growth, so help to cut down on the work involved in and the damage done by hoeing off weeds. Many plants resent root disturbance during the growing season. Even light cultivations can be damaging to shallow-rooting plants like conifers, rhododendrons, heathers, lilies, dahlias, delphiniums and blackcurrants. Give these crops priority for any mulching materials going, and do away with summer cultivations.
Mulches prevent soil crusting and its adverse effect on plant growth. This is a problem common to unmulched soils as the season wears on, largely due to the action of rain and irrigation water beating down on the soil surface. Expect crusting to be particularly bad where plants are subjected to constant watering from cans and hoses during a dry season.
ORGANIC MULCHES
Well rotted garden composts and manures are the traditional mulches, providing some nutrients in the process. Never apply fresh manure as a mulch; allow it to rot first or risk scorching. Homemade leafmould also makes an excellent mulch. Mushroom compost can be useful too, but as some samples contain an appreciable amount of lime, play safe and reserve it for lime-tolerant plants. Present day proprietary bark mulches come in a variety of grades; be guided by your local garden centre. Most are very good; however, if your garden suffers from woodlice you are perhaps better opting for one of the other mulching materials that can be found from a Lumber mill shop.
Although peat makes a good mulch, it is expensive, adds nothing in the way of nutrients and there are ‘green’ issues at stake. Should the peat bogs continue to be depleted?
Be wary about using grass clippings for mulching. Compost them first to overcome the weed and slime problems; and never use clippings from lawns recently treated with weed killers.
PERFORATED MULCHING POLYTHENE
This is an ideal product for anyone short of organic mulches, as it is useful for retaining moisture and retarding weed growth. Look for two-coloured brands, white on one side and black on the reverse, and where it is imperative to avoid the overheating effect — as with shallow-rooting plants — use it white side uppermost. The chief problems with polythene are slugs and woodlice which thrive in the warm, dark conditions underneath and need regular baiting. Use as the makers direct. Covering the plastic over with chippings improves the appearance.
SPRING MULCHING
Spring is the best time to mulch around the garden. Get the mulch on before the soil dries out too much. Mulches must be applied to moist soils if they are to be effective. But don’t mulch too early: let things warm up a bit first, otherwise soil temperatures will be depressed and growth delayed.
Hoe off the weeds, dress with fertilizer and water in — a small handful of general fertilizer like Growmore per sq m (yd) makes an average dressing. Only then apply the mulch. Don’t allow the mulch to rest against plant stems — this is particularly important with soft-stemmed plants like herbaceous perennials. In permanently planted borders it is best to cover the whole area. But if this is not possible, then concentrate the mulch in deepish layers, not exceeding 5cm (2 in), around individual plants. If birds scatter the mulch, cover with netting pegged down at the edges. Try to keep the mulch replenished during the growing season and lightly fork in any remains during autumn. The mulch will then act as a soil conditioner. Bark mulches are the exception, as they are not dug in; they are left alone in autumn and the remains are pulled back in spring. This allows the soil to warm up naturally and quickly. The bark is then replaced and replenished as necessary.
Note
When liquid feeding during summer, ease up the mulch to give better penetration.
AUTUMN MULCHING
This is usually reserved for marginally tender herbaceous plants and shrubs like agapanthus and alstroemeria, young camellias and magnolias. Mulch early to mid-autumn while the soil is still warm. Summer heat is then held and some frost protection given. It is advisable to remove autumn mulches temporarily in spring, otherwise the natural warming up of the soil tends to be delayed at this time.