Mulching with Purpose and Precision
Mulching is a top priority for a healthy garden. It does so much work that it’s hard to oversell the importance. A proper mulch maintains the integrity of the soil beneath it, protecting the earth from drying out under the sun and/or washing away when the rains come and/or blowing away in the wind. It creates water retention, mulched gardens credited with requiring as little as ten percent of the watering that other gardens do. Mulching prevents weeds, provides habitats for useful insects and microorganisms, and moderates soil temperatures. The right type even feeds the soil as it decomposes. In other words, it’s a good idea.
To be completely honest, I have been a crazy advocate of mulching, especially when people with modern gardens invariably ask what I think they should do to improve their plots, but I am not always the most productive of mulchers…mulchsmiths…mulchmen. I’m lazy, simply throwing down whatever organic matter is on hand, and perhaps, in my defense, this has been because I’m doing my best to use what’s on site. Despite having had success with my devil may care method of mulching, I know it’s not actually the best way, that just as different plants require different inputs, different mulches deliver different goodies. So, while I know my mulchful ways are a good practice, I’ve decided it’s time to start practicing them better.
A General Rule of Green Thumb
For me, and I think many fellow permaculturists, the idea of mulching with inorganic materials—those popular plastic sheets particularly—is simply not part of my MO. I’ve also come across the idea of using shredded car tires, which I, of course, appreciate in its repurposing but ultimately would not choose for my gardens. Mulching this way feels counterintuitive to me. Forests and prairies don’t come from such beginnings, so why would my gardens? These methods have notable benefits, plastic being impenetrable for weeds, rubber’s durability, but they also fail in many ways, which is why nature doesn’t do it like that.
Similarly, I’m not super interested in importing a bunch of material organic to a site. I don’t like the cost, for me or the environment, and while I’m certain at times it is of great value (and I’m not above it, especially on a local level), the ultimate goal is to not require those external inputs. The goal, I believe with permaculture on the whole, is to create healthy, waste-free cycles that don’t require outside sources. In other words, mulching, while seriously important, shouldn’t be a serious expense or require serious transport miles. That’s not how this whole thing is supposed to work.
My Favorite Mulching Materials
Mulching materials are simply too abundant and varied to require things like plastic or post-consumer, biodegradable weed mats (even though the right intention is there, it still requires production and packaging). Truth be told, as many others do, I like to use things like outdated newspapers and old cardboard boxes as weed-blockers, and they do the job of a plastic or weed mat well. When it comes time to mulch, despite being an import, I do keep my eye for newspapers and cardboard, as they are effective and accomplish repurposing without adding to my mulching footprint.
Otherwise, the rest of my mulching materials come from the land. Lawn materials are easy to find, and that includes grass clippings, leaves, pine needles, fallen branches, twigs, bark, as well as—in some desert settings—rocks. Of course, with more established systems, there is the opportunity to build compost heaps and leaf molds and/or grow hay and straw within planting cycles. Then, there are local byproducts possibilities—grain husks, sawdust or wood chips—that can work, are often free for the taking, and—if planned correctly—require little in the way of transport. Put simply, if it was part of a plant, fair game. That’s how the forest works.
How to Take Mulching to the Next Level
Of course, as with most things permaculture, we can take our simple and effective method—mulching in this case, but that applies across the board—and inch it further and further along in its usefulness and efficiency.
For me, that has started with recognizing a simple difference between what I’m using to mulch: carbon to nitrogen ratios. As with composting, controlling this makes a huge difference, and I try to view my mulching as composting in place, my intention being to simply add more mulch as the old layer breaks down into rich soil. So, when using high carbon elements, like dried grasses, husks, and wood, it’s important to realize that these things will deplete the soil of nitrogen, and this can be countered by adding a nitrogen element, such as fruit scraps, fresh grass clippings, seaweed, compost or manure beneath the mulch.
From there, it’s been learning via mistakes, and there have been some harsh lessons, resulting in plies of wind-swept mulches, rotten plant stems, and hundreds of “volunteer” plants popping up throughout my beds. So, I try to consider where and what I’m mulching: Will it get blown away, washed away or carried away by some element of nature, and ultimately how can I adjust for that? Well-placed rocks and logs work wonders. I keep my mulches off tree trunks and plant stems so that the rot doesn’t spread to the plants I’m trying to grow. And, most importantly, for all that is holy, I grow increasingly more careful when using things like hay or young compost that likely has thousands of unwanted seeds just dying to sprout up next to and choke out crops.
Tips for the Mulching Masses
There are other considerations and techniques that can make mulching more profound, and for those like me, who never seem to tire of experimenting with such things, here are some mulching moments to mull over.
• I can’t remember where I heard about this technique for removing seeds from grass, hay, leaves and so on, but I’m in my first stages of giving it a go. Put any sort of seed threats in the chicken yard before using it for mulch. The birds will eat all the seeds, scratch it up, and add a little nitrogen to the mixture. It feeds them then feeds the garden, which will supply more fodder for the chickens.
• Let things mature, and like wine, they just get better. This has been difficult for me because I’ve tended to volunteer on farms where I’ve introduced the idea of mulching and often composting (Doesn’t that sound crazy!), so I’ve collected grass clippings, leaves, and other compostable materials to use right away. However, with more time, these things work even better, or at least more immediately, with less seed worries and higher microbial populations.
• Different types of material and amounts of mulch work better for different seasons, climates, and weather. Loose straw, bark, and shredded leaves will create an airier, more water permeable, and cooler mulch that may work better in hot summer months. Why not give such things a thought or two when applying mulch?
• Mulch is great for all types of soil, but being aware of which type is being mulched can make a huge difference. A heavy, wet clay soil might not do so well with a moisture retentive mulch adding to it. Similarly, covering something like sand with a layer of big leaves (Forget plastic!) that might prevent water from reaching plant roots wouldn’t be a great idea.
• Color mulches appropriately when possible. Darker mulches will collect more heat and could be helpful in cooler climates (or a detriment in hot ones). Which makes more sense, a layer of dark leaves or of light-colored straw? Simply add a new top layer to suit the need of the hour.
Ultimately, though, what I find most important is simply to mulch. Bare soil is a place for pioneering weeds to flourish and finicky crops to perish. Many times I’ve seen a garden go from dreary and dry to green and thriving from nothing more than a good layer of mulch. Do it three inches thick and don’t forget to do it again. Essentially, our mulching replaces, perhaps within our gardens even enhances, the natural process of the forest or prairie mulching itself, and those systems seem to be worthy of replicating.