Some of the best things in life are free, and the abundant energy of the sun is one of them. This is very good news for those of us who work with garden and agricultural soils, which are home to hundreds of thousands of crop pests: insects, nematodes, termites, arthropods, rodents and weeds, as well as fungal, bacterial and viral pathogens. The power of the sun can be used in a passive way to defeat a number of these barriers to productivity, using a process called soil solarization.
Conventionally, since at least the 1930s, soil sterilants, like methyl bromide, have been used to fumigate agricultural soils and kill all sorts of organisms, whether or not they are harmful to the crop. Because this chemical depletes the ozone layer, its use has been steadily declining in most of the world since the Montreal Protocol on Substances that Deplete the Ozone Layer.
Although a solar alternative to using dangerous chemical fumigants has been documented as being used in ancient times by farmers on the Indian subcontinent, it didn’t really catch on here until the mid-1970s.
Grafting is a task most gardeners associate with trees, but there are numerous applications of this garden skill in working with herbaceous or annual plants. Chiefly, grafting is a viable way to gain more productivity with vegetables in the Solanaceae (or nightshade) family, which includes tomatoes, peppers, eggplants, potatoes, and ground cherries.
New novelty grafted nightshades have made it to market in recent years, like the “Ketchup and Fries” or “Pomato” plant—a cherry tomato grafted onto a potato rootstock—and the “Egg and Chips” plant—an eggplant grafted to a potato rootstock.
Copper tools, sculptures and tape—there are a lot of garden products that use this malleable elemental metal. So what does all of it actually do for a garden?
Often heralded as a sort of natural or passive slug and snail repellent, copper in the form of tape on pots and rings around plants are purported to chemically and electrically deter gastropods from munching on plants. However, Robert Pavlis, who curates the blog “Garden Myths,” says the effectiveness of these tools is overstated. It’s certainly a mild dissuasion, but a determined pest can safely cross its barrier. So even though copper isn’t exactly a panacea for the prevention of slimy invaders, it does have other important roles to play in cultivation.
Bagged or baled peat is a regular offering at most garden centers, but in recent years, more attention has been paid to how this histosol is unsustainably extracted from the earth.
Peatlands—also called bogs or mires—are unique and vital water-saturated habitats that house a number of threatened species: Acidic-soil lovers, like carnivorous plants and heathers, are among them. Like forests, peatlands are carbon-sequestering sinks, often hosting thousands of years of successive layers of low- and slow-growing plant deadfall, as well as sphagnum moss.
When peat is harvested in strips for use in the garden (or worse, for use as fuel), these delicate biomes that have taken eons to form are irreparably damaged. In building gardens that require low pH or high-organic-matter soil, consider a number of sustainably-produced alternatives to keep the integrity of these non-renewable ecosystems intact. Although these solutions require some experimentation, they provide the basic building blocks for rich organic soil.
Who would have guessed that rope made from a plastic soda bottle would be strong enough to tow a car? An ingenious little device, the brainchild of French entrepreneurs and simply called a “plastic bottle cutter,” allows anyone to make a upcycled plastic rope at home in varying widths. With a modest funding goal of €8,500 on Kickstarter, the duo has raised €293,000 for their business in less than a month.
Sandy soil, while providing excellent drainage, presents a challenge in terms of both irrigation and keeping nutrients in the soil. Vital plant nutrients, like nitrogen, phosphorus and potassium, which have a tendency to leach below the root zone of sandy soils when excessively irrigated, will remain present and available in the topsoil layer if more carbon is added. Adding carbon to the soil is as simple as adding more organic matter. I’d suggest adding successive top-dressings of mulch as they decompose.
Ideally, a mulch layer will also soak up water like a sponge, keep the soil below it cool and prevent excess evaporation of water. Mulch also provides habitats for members of the soil life web, like microorganisms, invertebrates and the root-like organs of fungi called mycelia.
Before You Mulch
Adding a soil conditioner to your sandy soil before mulching will do wonders to improve upon the good work of the organic matter. There is no better ingredient to remediate sandy soil than raw sources of carbon, like biochar.
Certain plants are adapted thrive in soils that have an acidic pH—that is, a pH below 7—and cultivating them means paying attention to soil chemistry. Often, these plants are called “ericaceous,” because many of them are, or resemble, members of the widespread Ericaceae family. The prototypical representative of this botanical family is heather (Erica spp.), but it also includes a diversity of other well-known and commercially or horticulturally-valuable plants, like cranberries, blueberries, huckleberries, azaleas, mountain laurels, gaultherias, and rhododendrons.
More broadly, acid-loving plants are called “calcifuges.” The name, meaning “to flee from chalk,” references their intolerance of alkaline or lime-heavy soils, which are full of carbonite.
Planting trees—especially fruit trees—from seed is always a bit of a gamble. Apples, for example, produce seedling offspring that can be referred to as “extreme heterozygotes.” This means the genetic possibilities in an apple seed are staggering, and there are no guarantees the resulting fruit will be palatable.
Unlike apples, however, citrus plants have more of a propensity toward consistency. Their seeds have a unique characteristic called “nucellar embryony” (Nu+), meaning they can contain a genetic clone of the parent plant. So when planting a seed from a Meyer lemon, for example, you may very well plant another Meyer lemon.
The substance most of us know as coffee is derived from plants of the genus Coffea, which is comprised of small trees or shrubs that evolved in Africa and tropical Asia. Cultivation of coffee is now widespread wherever the climate allows, especially in Central and South America.
The global love affair with this plant is mostly due to its natural defense against herbivores: It produces a bitter alkaloid called caffeine, which is one of the world’s favorite legal drugs. Not only appealing to humans, the caffeine in the shrub’s nectar is enough to provoke pollinators like bees to visit its blossoms three times as frequently as those of other plants.
Rhubarb (Rheum rhabarbarum) is one of those plants that usually sits relatively undisturbed in the corner of the garden for years, perhaps occasionally making it to the table in the form of pies or crumbles—that is, when sweet berries that offset its tangy flavor are also in season.
Despite its lush foliage, bold stalks and towering, long-lasting blossoms, this plant is a neglected perennial vegetable and is rarely considered to be an ornamental addition to the landscape. However, because rhubarb is as gorgeous a groundcover as it is an excellent producer of calories and biomass, it should be considered a candidate for larger plantings in gardens both edible and ornamental.
Through a process called phytoremediation, houseplants can give your indoor living space a breath of fresh air....