Vegalab (vegalab.com) is a company that has developed biopesticides that highlight a select group of plant and fungal extracts for their pest control properties.
Biological control, where compounds from living organisms are utilized in pest control, is a rapidly expanding field. Vegalab has utilized a saponin found in Camellia sinensis – the same tropical plant whose leaves are used for making common tea – for slug control. This Chinese camellia species is not to be confused with the Japanese camellia (Camellia japonica), the camellia with enormous flowers that bloom each winter. However, the tea plant is also suitable for growing in Southern California, reaching a height of 15 feet with fragrant white flowers that bloom in the fall.
You can find tea plants, in addition to hundreds or varieties of ornamental camellias, as well as several dozen other camellia species, at Nuccio’s (nuccionurseries.com) in Altadena. The saponin in tea leaves belongs to a group of botanical compounds that confer resistance to certain insect pests, as well as immunity to bacterial and fungal diseases. Saponins have a soapy or emulsifying property, meaning that they act as surfactants, sticking to leaf surfaces and thus minimizing the amount of product that needs to applied for slug, as well as ant, deterrence.
Another Vegalab biological control product utilizes the root of shrubby sophora (Sophora flavescens) to combat mites and larvae of all kinds. It has also shown effectiveness in controlling aphids, thrips, whiteflies, and planthoppers. The pagoda tree (Sophora japonica) is a related species that is grown ornamentally in our part of the world. It grows 25 feet tall and forms a perfectly symmetrical dome that casts enough shade to picnic under it on hot days. A leguminous pod-forming tree, its fragrant yellowish-white flowers bloom abundantly in the summer.
Vegalab is using a by-product of fungus metabolism to combat fungus – powdery mildew fungus, to be precise. Powdery mildew is the most common foliar fungal pest, which may appear as spotty, tactile white growth on virtually any plant when conditions for its proliferation – leaf surfaces that stay moist for several hours in warm temperatures – are present. Fungi that produce enzymes that break down cell walls are grown under controlled conditions and then these enzymes are isolated and sprayed on plants susceptible to powdery mildew fungus. The enzymes break down the cell walls of the developing fungus before it can get a foothold and cause damage. A similar product is used for control of fungal spore germination and is derived from thyme, the popular culinary herb; even where the fungus is already established, this product can be effective in halting its spread.
With the heavy rains we experienced this winter, mushrooms are being noticed in our gardens that have not been seen in years. Forays into the wild are also yielding large crops of edible mushrooms such as morels and chanterelles that connoisseurs of these saprophytic treasures have not encountered in two decades. To learn more about our local mushrooms, you might want to attend a meeting of the Los Angeles Mycological Society. This group meets the third Monday of each month from October through May (except February), at 7:30 pm in the Verdugo Room of the Sparr Heights Community Center, 1613 Glencoe Way, in Glendale. A mushroom identification hour, starting at 6:30 pm prior to the monthly meeting, is an opportunity to determine the edibility of mushrooms you may have foraged, whether at home or on a hike.
Ellie Gardner is an African violet variety whose leaves are dappled with cream and pink markings. Its flowers have the appearance of miniature pink roses and it blooms non-stop as long as plentiful ambient light is available. There are a plethora of African violet varieties with variegated foliage and you can find more than a hundred of them, listed as sports, at africanvioletsocietyofamerica.org
Browsing the site, you will also discover everything you need to know about growing African violets. Buckeye Cranberry Sparkler, winner of the Society’s outstanding African violet of the year three years in a row, has green leaves with broad cream-colored margins topped by a large clutch of raspberry-colored flowers. Search “variegated African violets” for an adventure in unexpected and unpredictable foliar design among the seemingly endless number of varieties of this most popular of all indoor flowering plants.
California native of the week: Of the 12 species of California native lilies, leopard lily (Lilum pardalinum) is the easiest to grow. It is recognizable by its pendant, reddish-orange, turban-like flowers with multiple spots. It can grow in the sun but usually does better in partial shade since it prefers somewhat moist, if well-draining soil. Wayne Roderick, writing in “Pacific Horticulture,” regales the leopard lily as follows. “It is so easy to grow that it can become almost invasive! It grows to about five or six feet high with as many as 15 bright red flowers on each stem. If the plant likes the location, a single bulb can become a large clump of 40 or 50 in less than five years.” That’s an invasive problem I’m sure all of us would welcome. Carole Bernstein, in “California Native Plants for the Garden.” suggests planting it under riparian trees such as sycamore and alder, in the company of “giant chain fern, coral bells, and western azaleas.”
Please send questions, comments, and photos to joshua@perfectplants.com