Allergy sufferers rejoice! You needn’t be afraid of the garden. You can stop allergies and asthma with smart landscaping. You read that right: you can STOP allergies and asthma with the right plants in your home garden.
If you are one of the millions of people with allergies or asthma, then you are going to want to read what horticulturist Thomas Ogren has written in his book, The Allergy-Fighting Garden. This totally unique book shows you how to avoid plants that trigger allergies and to create a garden that will actually protect you by trapping pollen and cleaning the air around you.
Thomas Ogren’s innovative system for combating allergens is based on the crucial matter of plant sex. By replacing troublesome male plants in your yard with pollen-blocking female “pollen screens,” allergy sufferers can reduce or eliminate their symptoms. More than 3,000 plant listings are included, accompanied by an easy-to-use allergy ranking scale of 1 to 10.
Today Thomas joins us as guest blogger to share the basics of the OPALS™ scale he created and a list of the top 10 allergy-fighting plants you can add to your garden today!
OPALS™ is an abbreviation of Ogren Plant Allergy Scale, although it is sometimes said to mean Ogren Pollen Allergy Scale. The scale runs from 1-10, where 1 is allergy free, and 10 is the worst, the most allergenic. A great many #1 ranked plants will be all-female selections, and likewise, many but not all #10 ranked plants will be all-male clones. Female plants (which shed no pollen at all) are allergy-fighting because they trap and remove pollen from the air.
OPALS™ makes it possible for gardeners to create their own landscapes that are completely allergy-friendly.
Although OPALS™ is focused on pollen prevention, there are other allergenic factors taken into consideration per the rankings, in particular odd odors, fragrances that might trigger allergies, and in particular plants that can trigger skin rash or itch through close contact. The actual amount of pollen produced is an important factor, but more important is the potency of the pollen.
Top Ten Allergy-Fighting, Allergy-Friendly Plants for the Home Gardener
- Pansies produce a tiny bit of pollen and it never seems to make anyone ill. They are entirely insect-pollinated and grow well when the season is cool. Pansy also includes their smaller cousins, the Violas (OPALS™ 1).
- Hollies (Ilex species) are very easy plants to sex; the female plants make red berries and the male plants make none. Male Holly plants can trigger allergies and many new female cultivars (such as ‘Nellie Stevens’) will make a good crop of red berries even without any males around. Never buy a Holly plant unless it already has some berries on it; they’re your assurance that you’re getting a pollen-free female plant (OPALS™ 1).
- Impatiens comes in many colors and sizes, but all of them thrive in partial shade with good moisture. Like the Pansy, each pollen grain in an Impatiens flower is large, sticky and does not become airborne. Easy to grow and very floriferous, all kinds of Impatiens are terrific allergy-friendly garden flowers (OPALS™ 1).
- Nepeta nervosa, Catmint, is a shade-loving hardy perennial that produces little pollen but a great deal of sweet nectar, making it a favorite of pollinators. Easy to grow and easy to propagate from cuttings, Catmint is a good addition to almost any shady garden spot (OPALS™ 2).
- Dianthus, Sweet Williams, are short-lived perennials for full sun. Easy to grow, quick to flower, and fast to re-bloom after deadheading, there are hundreds of fine cultivars of Dianthus. Many forms will lack all (pollen-bearing) stamens, and be essentially all-female plants. These all- female Dianthus are OPALS™ 1, but no type of Dianthus ranks higher than 3.
- Beautybush, Callicarpa dichotoma ‘Early Amethyst,’ is a small, shrubby, deciduous perennial, hardy in zones 5-10. ‘Early Amethyst’ makes a small amount of pollen but the plant is mostly female and, being self-fertile, sets a good crop of fabulous-looking berries each year. Flowers on new wood, so prune it back in very early spring (OPALS™ 2).
- Snapdragons, Antirrhinum majus, are hardy annual flowers for all zones. In hot summer, mild winter areas snapdragons grow well in the winter. The pollen in each flower can only be accessed when opened (usually by a bumblebee) and then it snaps shut as soon as the bee leaves. One of the best (OPALS™ 1).
- Cuphea, Cigar Plant, is a half-hardy perennial for the warmest zones, and used as an annual in zones 7-3. Easy and fast to grow, quick from cuttings, the little purple flowers attract many native pollinators and shed next to no pollen (OPALS™ 2).
- Salvia nemerosa is a perennial hardy in zones 6-10. Easy from cuttings, the flowers make no pollen but are very rich in nectar, making them attractive to native bees, butterflies, and hummingbirds (OPALS™ 1).
- Cranesbill, Erodium spp., are evergreen perennials for zones 8-10, best in shade in hot inland areas. Cranesbill is grown as a semi-hardy annual in colder areas and it is always attractive, free flowering and pest free. Related to true Geraniums, Cranesbill is quite allergy-friendly (OPALS™ 2).
That is just a taste of the plants listed in The Allergy-Fighting Garden. With many new pollen-free plants to choose from, as well as clearly marked “worst offenders” to avoid, this is the ultimate resource for home gardeners and professionals alike who want to build healthy, safe, and beautiful gardens that everyone can enjoy.
A special thanks to Proven Winners for providing some of the photos for this article, showcasing gorgeous varieties of allergy-fighting plants. The snapdragon image in the title is Angelface® Dark Violet Summer Snapdragon Angelonia angustifolia hybrid and can be found here.
Reprinted with permission from The Allergy-Fighting Garden by Thomas Leo Ogren, copyright (c) 2015. Published by Ten Speed Press, a division of Penguin Random House, Inc. Photography (c) 2015 by Tom Ogren.