Make use of the leaves and twigs that litter your garden, writes Stephanie Choo
DRIED leaves and twigs (leaf litter) provide organic fodder for any landscape. In a park that I often visit, I have noticed that leaf litter is left on the grounds as mulch. Micro-organisms are constantly decomposing the litter layers into humus and organic matter. Decomposition is nature’s way of releasing mineral nutrients and recycling them again.
THE NUTRIENT CYCLE
On the forest floor of the rainforest, as the thick layer of nutrient-rich vegetation parts break down quickly in the hot and humid climate, nutrients are released and returned to the soil. Roots of plants absorb nutrients from the fertile soil. The nutrients then travel up the trunks or stems to produce new foliage including leaves. When the leaves decay, they fall back to the ground.
We can put this form of recycling to work in our gardens too.
MULCHING THE GROUND
Leaf litter makes great mulch. The leafy layer keeps the soil temperature down and prevents water from evaporating from the soil. Over time, the mulch improves soil biology, structure, aeration and drainage.
Therefore, mulching around the bases of trees and shrubs creates a cool, moist condition with plenty of oxygen to keep the roots growing. Strong roots are the key to healthy plants.
However, mulch, which is piled too high can attract pests, restrain water from reaching the roots and starve the ground of oxygen. When the roots cannot breathe, they will die. So pile up not more than 7cm thick of mulch at any time. Also, ensure that the mulch does not touch the trunk or the main stem of plants as those parts of plant will decay in moist environment.
ENRICHING THE COMPOST
Leaf litter is carbon-rich and is a brown material that is necessary for proper composting. Once composted, leaf litter becomes soil conditioner or fertiliser.
A compost heap can be made using a pile of leaf litter that has been dried in the sun. Shred the litter by running over it with a lawn mower or by hand with a pair of shears.
The smaller the pieces, the faster the composting process. Pile up a large leaf litter of about 10cm high over soil in a dry, warm and sheltered position in a perforated compost bin. Moisten it with water before adding a layer of green material like fresh grass, or any green clippings of the same height.
Water and add a one centimetre thickness of garden soil to each layer. Continue building alternate layers of brown and green materials until the heap is about one metre high and wide.
Mix the layers together thoroughly with a garden fork or something robust and keep the pile as moist as a wrung-out sponge. Cover with a tarp or lid.
Turn the pile once a week and the compost will be ready in two to six months’ time.
• In the garden, leaf litter can easily clog up the drains, paths, ponds and water features. Remove any debris in those areas regularly.
• Stop leaf litter from being blown away by prodding the pieces of litter into the soil
or adding a layer of compost on top.
• One simple way to reuse
the leaf litter is just by
tilling in a thick layer of shredded leaves into the
soil. As they break down,
the nutrient-rich litter
will improve the quality
of the soil.