Mulch is probably the very best way to conserve water already in the ground and grow the flowers that lighten our lives as well as the vegetables that delight our taste buds and satisfy our hunger. There are many different ways of mulching the garden:
- shade mulch
- rock mulch
- paper mulch
- vegetable matter mulch
Each of the above is a desirable way toward a desirable outcome and if there is a chance to have several kinds of mulch at once all the better, as long as it fills the need of the plant and saves the water in the ground as expected. So looking at each of these mulches in turn we might find something that can be done about reducing the amount of water we use for growing vegetables and brightening up our lives. Remembering that sweet lettuce leaves are grown by keeping water up to them in quantity as they grow and having enough soil nutrient or adding sufficient nutrient during their growth cycle so the plant is able to make the most of the water it receives to deliver that taste and texture sensation we want. Some vegetable plants will not do well in just moist soil with periods of water shortage. We will only reap the favour and texture that we offer the plant to survive or thrive.
The Shade Mulch
This mulch can be natural and comes from other plants that are in the line of sun, mostly during the afternoon when the the heat from that source is at its greatest, and when the plants have already absorbed sufficient light and warmth from the mornings offering of that orb. The problem with shade mulch is that it usually comes from living trees and shrubs and these compete for water with the plants that they are shading. Though a shade mulch can be created from shade cloth or certain plant stalks and any material which inhibits the sun, and will be of benefit as a wind break as well, it is never as pleasing to the eye, because restricts the view past and over the garden. However there is no doubt that it works, though in the case of the shade cloth there are no branches for the birds to nest in either.
Rocks and stones have the benefit of never requiring to be renewed in the gardeners lifetime, and that is a bonus of sorts. They can be dug in below the soil surface, and they will retain water at their base as if they are above the ground, but the soil which is on top of them will dry out and where this soil touches the moist soil below the stones will also suck it dry and allow it to evaporate though more slowly. It is best to place the rocks or stones on top of the soil for gardens that are oft replanted anyway, though handling the rocks at each replanting is undertaken can become tedious. These rocks, stone or gravel mulches will ensure that water is allowed to reach the soil beneath it quickly and without any loss during rain or watering. That is very important in areas where the rainfall is unpredictable and unreliable in both timing and volume. The benefit of rocks and stones within the top 150mm of the soil has not been looked at in detail and will probably deliver some interesting revelations. Rocks do wear away, and plants do secrete certain substances that some might call mild acids to eat away at the elements the plants need and the rock and stone contains.
Paper mulch using newspapers or other papers that were once trees is quite reasonable, but as always depending on the garden conditions. The inks used in today's printing industries is not poisonous as it once was, however, what it does to soil and plants is not known either. Some might assume it does nothing, but there is not anything in this world that doesn't have an affect. Papers can be shredded and that assists with the breakdown of the mulch and water penetration to the soils surface, and it will disappear more quickly and become a water absorbent element of the soil as it does so. It can also be placed on the soil as sheets, and this has a different effect. But if the sheets are large and depending how many are used in a group, they will not allow the water to penetrated into the soil as easily. These mulches, because they are water absorbent are not as good in areas where the rainfall is light and low in volume and relied on as the main water for the garden. The reason being that only the mulch is watered and absorbs much if not all of it and the soil beneath experiences very little moisture and seldom enough to travel down to plant roots.
If placed in paper mulch is sheets on the garden, these must be held to the soil in some way. They can be handy if moisture can be maintained beneath them, to harvest earth worms by placing food for them under the sheets, but sheets of newspaper without being shredded are a cumbersome and high maintenance mulch in just about any conditions.
Vegetable Matter Mulch
All vegetable matter mulch is desirable because it will eventually enrich the soil, and compost mulches are very beneficial, as they usually contain worm castings and rotted vegetable matter that will release food for the flowers or vegetables which can be immediately utilised. These have the same drawback the other mulches with the exception rock/stone and shade, being they absorb water and only when completely soaked or if the rain is in deluge, allow water to travel down further to the soil and plant roots.
Grass and hay mulch is also very beneficial providing they are grasses without seed and if those to be used for mulch contain seed, it is not the invasive, difficult to eradicate type like bent grass [couch grass] or others that can make gardening a chore and is mainly weeding. The nutrient these undesirable weeds consume isn't returned to the garden, because the plants need to be physically removed and disposed of, or treated in a way that will make certain they and any seed is killed before being composted and returned to the garden.
Certain mulches like hardwood chips take a long time to break down. But because nature wants to break down the mulch, because it is not really something that fits in with the natural scheme of things to remain for a long period on the soil surface. The breaking down of these chips will deprive the plant roots they protect from the sun, of nitrogen, because this element will be used up trying to break down the high carbon wood chips. Though once the task is complete, the nitrogen will slowly become available to the plants again.
These are just some of the mulches that can be used. They are not exhaustive. The terrain and soil type and the plants to be grown will in many cases dictate the mulch that will suit the conditions. It must also be remembered as well, that some mulches are home for many insects and fungi. These thrive in the conditions that mulches create, and they are not to be discounted, as they also affect plants one way or another.