Colleen: Tom, could you give a brief overview about the basic concept of allergy-free gardening?
Tom: There are seven major concepts to allergy free gardening and all are based on the basic concept of Avoidance: 1. biodiversity, 2. mold/spore control 3. insect control 4. avoidance of non-organic allergens 5. avoidance of all male cultivars 6. placement in the landscape with regard to contact allergies and odor challenges 7. Use of OPALS/TM
1. Even with insect-pollinated plants, over-use of the same plant materials results in over-exposure to that particular pollen. Many landscapes now are all the same. The dentist's office has the same plants as the bank, and the bank has the same ones as many new houses. We need landscapes with more complexity, more species, more biodiversity.
2. We need to control mold spores and spores of all kinds. All spores, from any sort of fungus, mold, ferns, whatever, all spores have the potential to cause allergies. Over watering, planting too close, and a host of other cultural factors cause an excess of spores. Often from too many insects.
3. Insect control: Insect dander causes allergy. Insects also secrete large amounts of "honeydew," which is very rich and full of nutrients. On this honeydew grows mold, and then come the spores. Insects attack the weakest plants first. If a tree, shrub, houseplant, frequently has many aphids or whiteflies, mealy bugs, and so forth, there has to be a reason why. We figure out what the plant needs to thrive. Plants that thrive almost never have large infestations of insects. Could be many things: too much water, not enough water, poor drainage, lack of some fertilizer element, herbicide injury, cold injury, heat injury, wrong soil pH, or maybe just the wrong plant for that area. To control the molds and bugs we need the help of predatory insects and birds. Birds eat millions of insects daily. We need to attract them and keep them around. We need to use methods of killing insects that don't harm the plants, don't harm the beneficial population, don't harm the birds, don't harm us. I like....hey, it's in the book!
4. Avoidance of non-organic allergens: this means things like diesel smoke, most pesticides, herbicides, fungicides, many chemicals. These break down our immune system and leave us much more vulnerable to allergies. Often just one heavy exposure to these allergens can trigger this susceptibility to allergy. Learn to go organic as much as possible.
5. Male clones: these are everywhere. Through the "genius" of modern horticulture we now have an over-abundance of clones of male lawns, shrubs,
