I almost chose not to write this quick article, but there are so many people that visit my site who are brand new to Permaculture, that I thought it would be worthwhile.
Chop and Drop Mulching could be considered a basic core skill for Permaculturists. It is a little complicated, so I will do my best to explain it in a step-wise manner:
- Find a plant which could be mulched.
- Chop the plant down, or chop the leaves off the plant.
- Drop the plant or leaves to the ground.
- Walk away.
I hope I did not make it too difficult. (insert smiley face here!)
All joking aside, Chop and Drop Mulching really is this easy. Now there are some finer points one should understand, so I will elaborate a bit.
What plants do I use?
Almost any plant will do. Honest! The goal is for the plant to cover and smother less desirable plants (weeds), but we also want the mulch plant to rot fairly quickly and become part of the soil we are continuing to build. Woody plants will take longer in a Temperate Climate and are best avoided for mulch unless we only use the non-woody parts or chip the wood first. In a Humid Tropical Climate, woody material breaks down and rots so fast that it is a good choice for Chop and Drop Mulching. Herbaceous plants will work great in a Temperate Climate.
Are some plants “better” than others?
Sort of. Any plant that is considered a Dynamic Accumulator is a great mulch plant. These plants mine minerals and nutrients from deep in the soil and sub-soil. Mulching them allows these nutrients to become available to the more shallow-rooted plants. Nitrogen Fixing Plants are also great for Chop and Drop Mulching. As these plants rot, they will provide extra nitrogen to the surrounding plants. With that said, however, all plants will eventually rot and become soil.
When should I Chop and Drop?
Timing is vitally important. The general rule of thumb is to Chop and Drop Mulch when rainfall exceeds evaporation. This means we will chop plants right when the rainy season is about to start. Many places in the world have a “dry season” and a “wet season”. Some wet seasons are so wet it is called monsoon. In many Temperate Climates, even if there is not a vast difference in wet and dry seasons, there is a portion of the year where rainfall is more common. Just before the wet or rainy season starts is the time to get out and Chop and Drop Mulch. The moisture will help keep the mulch in place and will speed the decomposition process. If we chop in the dry season, the plant material will dry up and blow away at best, and it can become a significant fire hazard at worst.
Another thing to consider with timing has to do with the plant itself. If the plant is one we are trying to minimize in our landscape, then we will want to chop and drop just as the plants begin to flower, but before they set seed. We will allow that plant to put all its energy into building the flower structures, and then we chop it to the ground. Many of the plants we are trying to disadvantage are early successional plants (i.e. “weeds” to the common person). These plants are growing well in an area, because the soil is so poor that nothing else will grow. These plants are often Nitrogen Fixers and/or Dynamic Accumulators. The Thistle plants (which is an umbrella name for many genera and species of plants) are a classic example. In a natural succession, Thistle will come in and colonize a site. Over many generations, as the soil builds from Thistles growing and dying and growing and dying, other plants can move it. With Chop and Drop Mulching, we are speeding up this process. We are helping the land and soil fast-forward in time. We are building soil, favoring desirable plants, and disadvantaging less-desirable plants. That Thistle, which we chopped off at ground level, still has life left in it. It will put all its energy into growing again. Then, just before setting seed again, we chop it down. After this occurs a few times, the Thistle finally dies back. The deep roots rot in place which builds the soil even more and provides fast carbon pathways for other desirable plants’ roots and fungal/mycelial networks to expand.
So, if it is a non-desirable plant, we can Chop and Drop Mulch whenever (before!) the plant is about to set seeds. If it is any other plant, we want to Chop and Drop Mulch just before or right at the beginning of the rainy season or the period of time when rainfall is greater than evaporation.Subscribe to TCPermaculture.com and receive updates whenever a new article is posted!