Got mulch?

The Tropical Garden, Fall 2016

By Richard Campbell, Ph.D.

Recycling plant material for use as mulch or compost is an environmentally sound way to enrich our South Florida soils.

Our soils in coastal South Florida are shallow and composed of mostly nutrient-poor, high pH rock or sand. We have a monsoonal climate with a rainy, hot summer and dry, cool winter; summers bring the threat of tropical cyclones; and winters bring the occasional killing frost. Yet, given these edaphic (soil) and climatic limitations, there are ways to enhance our growing and gardening experience.

Mulching and composting offer the most environmentally sound method for us to improve our soil fertility. No plant material should ever leave your home garden. All plant debris, including leaves, twigs and branches, can be cut into small pieces and placed within the mulch or compost pile, either beneath a pruned tree or in designated areas. The circle of life and nutrient cycle will both now be realized to their fullest. Instead of losing this energy- and nutrient-rich organic matter and filling local landfills, plant material is recycled for use as mulch or compost in the vegetable garden and throughout the home garden.

As a seasoned home gardener you have no doubt heard the party line: Mulch and compost are the cure for everything from poor tree growth and insect control to improving the health of the Florida Bay. Well, it turns out that these mulch- and compost-mongers are right—these activities really are essential for home gardening in South Florida. A consistent mulching program will allow you to convert your home landscape into an organic system that relies on nature’s way and will change your entire gardening demeanor. No more need for commercial fertilizers and pesticides—only a firm pruning hand, a heightened ecological understanding and appreciation for the cycles of life.

It will take a number of years for your home landscape to fully embrace the mulch and composting system. Previous decades of poor stewardship are not swept away in a single season. You have to wait for the soils to recover from the years of other approaches. This recovery will take the form of a thriving soil flora and fauna, nourished by the organic matter that you will create. In nature, everything is a process and this process cannot be rushed. Make your labors part of the solution, but be patient and let nature take its course.

A hand saw, pair of hand loppers, a machete and hand pruning shears are all that is needed to embark on your new path. Twigs, leaves and branches removed from your trees can be cut up in place; if you prefer a more tidy approach, a special mulching area can be created. Let that membership at the local gym lapse, for making your own mulch will give you a great workout. It is also the best time to get your thinking done. Mulch piles composed of twigs, branches and leaves do not smell badly. On the hottest and rainiest months your mulch pile will have an organic aroma, sweet and slightly alcoholic. It is always a good idea to water the mulch pile during the driest weather. This will help the plant material break down faster into a product readily usable by your plants. If you are ambitious and sufficiently engaged in the doctrine, you can embark on a composting program as well. In the case of composting, there are many commercial contraptions to assist in your endeavors. If you prefer the zero- footprint approach, you can always make your own compost box, wire ring or pit. Compost piles can take your leaves, weeds and twigs as well as much of your kitchen refuse and other organic waste. Layering and turning will be your mantra, as the compost pile is indeed more time-consuming than the mulch pile. However, the end result—a living and healthful humus for your garden— can make any ordinary homeowner a master gardener. You can regale your friends with tales of the organic life and the saving of the earth, and actually be a part of it.

A common myth about mulch and compost piles is that they harbor all of the most vile and dangerous creatures of the wild. Most of us live in rather “tamed” locations, so it is highly unlikely that your well-groomed mulch piles will harbor bears or panthers (pythons perhaps, but they will prefer to live underneath your nearby home or shed). Actually, the mulch pile will serve as a home for lizards and frogs, mice and possums. There can be some tree rats, so a control program with owl boxes is always a good idea, and a rat-catching dog or cat is a good idea. There will be several harmless snakes around trying to eat some of the small creatures within the compost or mulch pile. If you leave them all alone, a peaceful coexistence can be achieved.

Weathered mulch and compost can be applied around each individual tree, or it can be applied in beds. You can pile it to a depth of 6 inches to 8 inches, but you must retain a 3-inch distance from the trunks of the trees so as not to burn the tender bark and feeder roots of small trees. The mulch will break down at an alarming rate here in South Florida, meaning that your work will never be done. Keep pruning, mulching, composting and applying.

You can also bring shredded plant mulch from tree trimming companies into your home garden, and this is a good complement to your own work. However, be careful of introducing unwanted weeds in commercial shredded mulch that has not been allowed to compost properly. Mulch can be purchased, but it is often expensive and may come with dyes and other chemical additives that are not conducive to an ecological balance or healthy plants.

Mulching and composting will allow you to achieve the gardening success that you have always wanted. It is not magic, but rather, nature at work. All of the plants within your landscape have evolved to take up nutrients from organic matter, provided from your decaying plant debris. It will be a bit awkward at first, but soon you will be moving effortlessly to the beat of nature and your mulch will be changing your home landscape and vegetable garden for the better.