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Photograph by Shari Kaplan
Both of these creeping Charlies began as cuttings from the same parent plant. They are easy to root and do well as houseplants or outdoors.
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Environmentally friendly pest control is a good idea
By Tony Tomeo
What I dislike most about working in the garden is the occasional need for pesticides. Although the very few pesticides we use are relatively safe, they remind me of how much more toxic chemicals were once commonly used in gardens and around homes. Many of the chemicals formerly used to control insects and diseases in the garden are no longer available, because they were found to have detrimental effects on the environment or present a health risk to those who come into contact with them.
Whenever possible, I recommend controlling pests without conventional chemicals. Not only are many of the "alternative" controls less damaging to the environment, but they may be more effective, because they do not damage populations of beneficial organisms. Many insecticides eliminate all insects, including the predatory insects that help control the pestilential ones.
For example, a nonselective insecticide would easily eliminate aphid infestations. But, because the predatory green lacewing population would also be eliminated by the same chemicals, the aphid population would recover more quickly without natural predators. Continued application of a pesticide necessary to control aphid recovery also prevents recovery of the green lacewing population.
Alternatives include physical controls, cultural controls and biological controls. If chemical controls are absolutely necessary, less toxic chemicals are preferred. Examples of physical controls include sticky barriers used to prevent ants from farming scale and aphid insects on garden plants, as well as copper tape used to block access to snails and slugs.
Cultural control involves selection of plant species that are best suited to each situation. For example, if snapdragons cannot be grown without rust problems, another species that is resistant to rust should be selected. Other fungal diseases may also be controlled culturally by timing irrigation earlier in the day and adjusting dispersion of water to avoid foliage.
Biological control does not necessarily require the introduction of predatory organisms; but may be as simple as encouraging proliferation of existing beneficial species, such as spiders and green lacewings. (Many plant species are attractive to beneficial insect species.) If introduction of predatory insects is preferred, selection should be appropriate to the target pest.
It is important to recognize that pest control does not necessarily imply complete eradication. Small populations of some pestilent insects or disease organisms may not necessarily be detrimental to the garden. In fact, a healthy ecosystem, in which insect pests are controlled by respective predators, includes a diversity of insect species.
The West Valley Clean Water Program has assembled a guide to pest control for the home and garden. Alternative control techniques and less toxic chemicals described in this guide may be useful for control of ants, mosquitoes, roaches, aphids, caterpillars, silverfish, snails, whiteflies and fleas. The West Valley Clean Water Program may be contacted at 408.354.5385.
Plant of the Week: Creeping Charlie
One of the difficulties of horticulture is the strange names given to many of the plant species common in the home and garden. Although creeping Charlie might sound like something to call the police about, it is actually the name of a once-popular houseplant, Pilea nummulariifolia.
Creeping Charlie may be used as a small houseplant, or groundcover, in pots of larger houseplants. Flowers are inconspicuous, but foliage is glossy green with scalloped edges. Stems creep along the soil surface and are easily rooted, if pressed into the soil, or buried slightly, while still attached to the main plant.
The roots prefer very well-drained, porous soil, with thorough but infrequent irrigation. The soil surface should dry between watering. Regular fertilizing with mild houseplant-type fertilizer will maintain deep green foliar color. Although creeping Charlie tolerates some shade, growth may be sparse if light is minimal. Scrawny plants recover quickly, if pruned and moved to a brighter area. If sun exposure is too extreme, foliage may fade.
Creeping Charlie is not always available at retail nurseries but may often be found in small pots at garden centers or home improvement centers. They are also easily grown from cuttings.
Horticulturist Tony Tomeo may be contacted at 408.358.2574.
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Los Gatos, California Since 1881
