Gardening Articles: Landscaping :: Yard & Garden Planning
Garden Guru: Thomas Ogren (page 2 of 2)
by Cathy Cromell
Ogren became hooked on gardening at a young age. He started sowing seeds when he was 5 years old and remembers his grandfather giving him a strawberry guava tree when he was 7. He obtained a Master's degree in agriculture and horticulture from CalPolySan Luis Obispo, later co-owning a retail nursery in Minnesota, and selling grape vines through a mail-order nursery in Los Angeles. Plants have never made him sneeze.
Unfortunately, allergies are on the rise in this country. In 1959, 2 to 5 percent of the population suffered from them. In 1984, the number was 12 to 15 percent. In 1999, it spiked to 38 percent. Ogren attributes these increases to major changes in our landscaping practices, in particular, the exclusive use of male plants, and monocultures mass groupings of the same type of plant. Plant breeders developed male clones to avoid the clean-up required with growing female plants, which bear messy seed pods or fruit. However, males produce prodigious amounts of pollen, which causes allergy symptoms when the microscopic grains are inhaled. Monocultures aggravate the problem by increasing the opportunity to be overexposed to an allergen.
Ogren has some suggestions for reducing the allergens in your landscape:
- If the plant variety you desire has female flowers on one plant and male flowers on another, choose the female plants because they will produce no pollen. Ask your nursery or garden center for female ash, willow, mulberry, juniper, and maple trees.
- Plant a diverse garden so that you won't end up with large numbers of any one allergen-producing plant.
- Select plants that are low-allergen producers. If you choose a high-allergen plant for some reason, install it at the edge of your property, away from windows and doors.
- Choose plants that are well-adapted for your area and maintain them properly. Stressed plants are attacked by pests, such as aphids, which produce honeydew. Mold quickly grows on the nutrient-rich honeydew, producing spores that are allergenic. "Also, a stressed male plant will put out 23 times the normal amount of pollen before it dies in an attempt to reproduce itself," states Ogren.
For more information on allergy-free gardening, visit Ogren's Web site at www.allergyfree-gardening.com/articles.php