GARDEN FANATIC: Much ado about mulching

Andy, a city gardener, recently asked, “If you could make one suggestion for the City Hall garden this month, what would it be?” That’s a good question, I thought, and because my livelihood depends on making thoughtful landscape suggestions, I could suggest that there are dozens of things a dedicated gardener could do to improve his or her garden. But none are more important than mulching.

Loose layers of organic or inorganic materials that are placed on the soil surface are mulches. The process of applying such materials is called mulching. The cultural practice of mulching serves many purposes. A 2-inch-thick layer insulates the soil from rapid changes in temperature and conserves water for plantings in the process. It reduces competition from weeds, prevents unsightly mud from splashing onto foliage and flowers, protects falling fruit from injury and gives the garden a “finished” look.

Almost anything that can be composted may be used for mulching. Ideally, the mulch is free of weed seeds, and has not been recently sprayed with a herbicide. All organic material has a tendency to withdraw nitrogen from the soil if not composted, and to overcome this, for each 160 square feet of organic mulch, 2-inches thick, mix in about one pound of ammonium sulfate. Consult your local nursery person for more details.

Planter mixes, redwood compost and composted, recycled green waste (see below) are excellent mulching materials for ornamental and fruit trees, shrubs, roses, vegetable beds, perennial and annual borders, and rock gardens. They serve the dual purpose of providing plant food.

Commercial products from Roger’s, Bandini and Kellogg’s are also good products for mulching, if you don’t have the space or inclination to setup a compost pile. Azaleas, camellias, gardenias and other acid loving plants greatly benefit from mulch of azalea mix, leaf mold or peat moss.

Inorganic mulches are materials that do not decompose, so they are more permanent than organic mulches. Available materials include gravel, coarse sand and plastics.

Black and clear polyethylene sheeting provides excellent control of weeds and can even be placed over existing weeds to kill them. This Saturday from 8 a.m. to noon, Tierra Verde Industries and Waste Management of Orange County will offer organic soil amendment to Laguna residents. This compost, recycled from green waste by the City’s residential recycling program, is ideal to mulch your garden. Plan on stopping by early at the Forest/Laguna Canyon Lot, with heavy-duty trash bags or trash containers, shovel and gloves, and start mulching!

See you next time.

STEVE KAWARATANI is married to writer Catharine Cooper and has one cat and five dogs. He can be reached at (949) 497-8168, or e-mail to plantman2@mac.com