The practice of chop and drop mulching has long been a core technique utilized by permaculturists around the world, but there is more to this concept than meets the eye. Before you begin incorporating this practice into your own permaculture design, there are some factors you need to consider.
In theory, chop and drop mulching is pretty straightforward – you find a tree or a plant that can be used as mulch; prune off branches, leaves, or the entire plant; drop these branches, leaves, or plants to the ground; and you leave it there. However, depending on the type of plant you’re pruning and the climate you live in, this practice may not be 100 per cent effective.
Which plants make better mulch?
While basically any plant will eventually break down and feed your soil, the point of mulching is to efficiently suffocate the undesirable plants that may be inviting themselves into your garden, allowing you to avoid the use of chemical treatments. You want the plant to cover the surface of the ground and begin to rot quickly, so it can start becoming a part of the soil.
Plants known as “dynamic accumulators” are especially effective, as these kinds of plants can actually help extract minerals and nutrients from the soil and sub-soil – and allowing your more shallow-rooted plants to access them. “Nitrogen fixing” plants are another great option for mulching, as they offer additional nitrogen to be used by adjacent plants.
However, all kinds of plants will eventually begin to rot, and will become nutrient-dense soil for your plants to feed off of.
How does the climate impact this process?
Depending on the conditions where you live, different plants will take more or less time to break down. If you’re in a temperate climate, woody plants like trees should generally not be used as chop and drop mulch – they take too long to rot, unless you chip the wood or just use the parts that aren’t woody. Herbaceous plants are a better option for this practice.
If you live in a humid, tropical climate, however, these kinds of materials will break down much quicker. You’ll be able to let tree branches fall to the ground and watch as they soon rot and become rich soil to feed your plants.
When should I practice chop and drop?
Whenever rainfall exceeds evaporation, conditions are ideal for chop and drop mulching. During the portion of the year where you see the most rainfall, that’s when you should start creating mulch. Not only will the added moisture help with the decomposition process, it will also keep the mulch in place – when conditions are too dry, it can blow away and even become a dangerous fire hazard.
Also, plants that you don’t want in your garden should be turned to mulch before they seed, to reduce the likelihood of these kinds of plants popping up in your garden later on. This helps ensure that your desired plants will benefit from the enriched soil, while the undesired plants will be eliminated before they have the opportunity to produce seeds.