Creating a Low-Allergen Garden

If plant allergies have you dreading spring gardening, help is here. Our tips for pollen control and integrated pest management will provide allergy relief.

Are you getting ready to start your spring planting? Or does the mere mention of gardening make your eyes itch and your nose run? A healthy low-allergen garden design can help get allergic gardeners back onto their patch of earth, sneeze and sniffle free.

At least one in six Canadians are afflicted with seasonal allergies (hay fever). Symptoms of seasonal allergies are usually more aggravating than life-threatening, although if left untreated, can occasionally lead to asthma and even anaphylaxis.

Oral allergy syndrome, a cross-reaction that prevents sufferers from eating several types of raw fruits, vegetables, and nuts, is also associated with hay fever.

Seasonal allergy symptoms can last the entire duration of the growing season, from early spring until late autumn, preventing gardeners from enjoying their favourite hobby. While heavily scented flowers may be the obvious culprits—especially for asthmatics—pollen and mold are actually the big triggers for seasonal allergies.

Blame pollen

Male or female?
Many of our ornamental and food plants can be either male or female. Males are the pollen producers, and should not be planted in low-allergen gardens.

What to do: female plants that produce fruit are  always a better choice, as are cultivars that have been bred to be sterile.

Pollination method
The method by which plants are pollinated also makes a big difference: plants that are pollinated by the wind contribute to air pollution and allergic reactions.

What to do: gardeners should encourage allergy-friendly pollinators such as birds, bees, and butterflies by planting attractive selections and providing appropriate habitat.

Shape and size
Flower shape and size are other factors to consider. A common misconception is that plants with large flowers, such as peonies, are greater allergen producers than plants with tiny, insignificant flowers, but that is usually not the case.

What to do: use plants with bold, showy flowers (especially ones shaped like trumpets, with the pollen buried deep within), as they tend to have very sticky, heavy pollen, and are usually pollinated by insects and birds.

Spurn mold

Keeping mold out of the garden is crucial and is easily accomplished by good planning and a little elbow grease. Too much shade from densely leaved trees in your yard will promote mold growth, especially during cool, wet summers.

Planting
Good air circulation is key to plant health (and therefore yours). Do not plant huge, sun-blocking conifers such as spruce and pine in southern and eastern exposures; they will prevent light and heat from getting to other plants in your yard and may contribute to mold growth.

Pruning
Keep all trees and shrubs judiciously pruned, and always remove fallen leaves in the autumn.

Mulching
Although using mulch around plants is an excellent practice, use clean rock instead of bark chips, which may encourage mold.

Watering
Consider your irrigation practices, and try not to water in the late evening, when temperatures have cooled. Water conscientiously, and do not give plants more than they need.

To lawn or not to lawn

The mold spores, pollens, and dust kicked up by mowing the lawn is a huge problem for seasonal allergy sufferers. Removing the lawn entirely is definitely an option for the afflicted, but many people enjoy the beauty and usefulness of turf.

If you are keeping your lawn

• Ensure it is in peak condition; cutting the grass too short and too often will stress the plants and cause them to produce more pollen.
• Select species of grass that are hardy for your area, especially types that do not produce a lot of pollen.
• Wear a mask while mowing the lawn, and use a reel mower to reduce air pollution. Better yet, enlist someone who doesn’t suffer from hay fever to do the job for you!

Location, location, location

The closer you are to the sources of pollen, the worse you will feel.

• Position pollen-producing plants well away from the windows and doors of your house.
• Do not use them as edging along a pathway, as you or your pets may brush up against them and track irritants indoors.

Timing is everything

Pollen levels differ depending on the weather, the season, and the time of day.

• Try gardening on calm, cloudy summer mornings, when weeds and grass release less pollen.
• In early spring, garden later in the day, when tree pollens are at their lowest count.

Practise IPM

Integrated pest management (IPM) is a set of practices governing how plant pests are controlled, with a focus on maintaining overall plant health and vitality over complete eradication of “bad” insects and diseases.

Individualized care and culture of every plant in your garden is imperative, and it may require some planning and research on your part to figure out which plants are most suitable for your low-allergen landscape.

Go native
You may wish to include hardy native plants in your garden, as regional selections may be more pest-resistant.

Look for good breeding
Some plant cultivars have been bred with special disease resistance and may be good choices.

Seek diversity
Above all, try to plant a diverse range of plants in your garden; sticking to only a few species of plants encourages unwanted pests. Remember that unhealthy, pest-ridden plants produce more pollen and encourage mold spores!

Go organic

Avoid the use of synthetic fertilizers and pesticides. Seasonal allergies weaken the immune system, and chemicals may do further damage to your health. Safer alternatives are available; sometimes all it takes is a little deadheading or pruning to get rid of the problem.

• Consider the use of beneficial insects such as ladybird beetles and certain species of wasps to deal with aphids and other “bad” insects.
• Create a safe haven in your garden for bats, birds, bees, and butterflies.

Thoughtful planning and careful planting ensure that seasonal allergies are no longer a part of your gardening experience.

Low-allergen plants to try

• dogwood
• peony
• black-eyed Susan vine
• gladiolus
• fir
• daffodil
• hollyhock
• pansy
• cherry
• iris
• nasturtium
• peach
• plum
• ash
• tulip
• zinnia
• hosta
• foxglove
• fuschia
• petunia
• Chinese lantern
• hens and chicks
• poppy
• carnation