Answer: As a general guideline for allergy sufferers, colorful showy flowers, which are pollinated by insects and birds, produce less pollen than non-descript flowers (such as the long, narrow catkins on many trees), which are wind pollinated. Pollen blown about by the wind is smaller, lighter and more likely to end up in our nostrils. The pollen that insects favor is usually heavier, stickier and less likely to move far from the plant (unless it's on the back of a bee.) However, your wife seems to be sensitive to showy flowers as well, so it's difficult to recommend what will or won't be a problem for her. There is a fairly new book out called Allergy-Free Gardening by Thomas Leo Ogren. He has created an "allergy scale," listing plants by their potential to cause problems. That might be a good place for you to start.
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