Green gardening is a term being bandied about these days that leaves some scratching their heads. What could be greener than gardening?
Depending on who's giving the definition, quite a bit. On one side of the constantly shifting line are those who believe everything that goes into the garden should be organic, from the compost to pest control measures. On the other side of the garden hedge are those who believe in better gardening through chemistry, and who point out that plants don't care if their nitrogen comes from natural or manufactured means.
Somewhere in the fertile middle ground are those who let the garden dictate the gardener's tools. These gardeners aim for organic but, when under attack by pests, may resort to chemicals, albeit the least toxic choices available.
As most gardeners will tell you, it's not as clear-cut as one might think. But no matter where your personal views may lie, there are ways to green up the garden, both in color and in the environment.
Annie Joseph spent more than two decades in the wholesale insecticide trade. Then one day she was contacted by a group of government agencies working to reduce the amount of pesticides that enter Bay Area waterways. They asked for her help in getting the word to retailers about a program to provide education to customers and include eco-friendly products on their shelves.
"I realized the stuff I was selling was contributing to the problem," Joseph says.
Here are some suggestions from Joseph for gardening greener:
Fertilizers: The greener choice is to use organic, slow-release fertilizers. Plants are not gluttons. They absorb only the amount of nutrients that are available to them and that they can use. The rest remains in the soil to be washed away by rain or irrigation, flowing into streams and creeks, and eventually into the Bay.
Fast-acting fertilizers can also speed up growth, which in turn attracts insects that like to feed on new, tender shoots. By encouraging rapid growth, you may also be creating a pest problem in your garden.
Pest control: The first step in green pest management is to decide your personal threshold for the little critters. Can you live with a few aphids? Once you've made your decision on how pest-lenient you'll be, you can make other decisions from there.
"A diverse garden is actually a healthy garden," Joseph says. "It brings in a lot of beneficial (insects). Go for variety and keep away from monoculture."
The greenest tool in the arsenal is physical control. Spray water to remove aphids and hand-pluck snails. Another green alternative is biological control, releasing beneficial insects into the garden, and cultivating plants that encourage beneficials to take up residence in the garden. Ladybugs and green lacewings love aphids; assassin bugs take care of beetles, caterpillars, hornworms and other insects. Creating bird-friendly habitats also can reduce insect populations.
If using chemical control, start with the least toxic and use the minimal amount. Be sure to read labels and follow directions, Joseph says. Failure to do so may eliminate your insect problems, but harm bees, wildlife or pets.
Organic insecticides also can be harmful, Joseph says, and overuse can produce toxic results in the environment.
"Some people think that because it's organic," Joseph says, "there's no problem. But there can be."
An organic pesticide that contains pyrethrins, a poison derived from Chrysanthemum cinerariifolium, is quick-acting, has low toxicity to humans and animals, and degrades within a day. But it's highly toxic to honeybees.
Neem, a popular biopesticide that upsets the insect's hormonal system and prevents it from maturing and producing more generations of insects, is nontoxic to humans but can cause problems with aquatic life if it reaches water.
Plastic: It's a bit ironic that plants usually are sold in plastic containers, and almost all fertilizers, mulches and composts — organic or not — come in plastic bags. Most nurseries will take your used plastic pots to return to the growers, but there's not much that can be done with most plastic bags.
Check to see if they can be recycled. If not, Joseph says, consider them for chores you might use a plastic trash bag or container for, giving them another life.
Reach Joan Morris at 925-977-8479 or firstname.lastname@example.org.