Why Garden with Native Plants

Paul learned that many of the plants growing in the understory of his parents’ forested land were invasive and not native and he wanted to learn how to contribute positively to the natural environment.  Native plants lived in North America before European settlement and evolved over millennia to feed and shelter native animals, insects, and reptiles.  New Jersey tea, a native shrub, is a premier nectar plant for 50 butterfly, bee, wasp, and hoverfly species.  

Growing native plants can help counter the effects of what Paul calls the Homogeocene Era, decreased biodiversity which results from the global movement of plants caused by people.  Only five percent of Southern Ontario’s natural areas are left.  Plants such as cylindrical blazing star and wild blue lupine are rare or endangered in their home ranges.  No lupines, no Karner blue butterfly.  Native species, with roots which can grow eight feet deep, are drought tolerant and prevent erosion.  They don’t require chemicals to look their best.  And they’re tough: Lorraine Johnson writes in her book Grow Wild! (1998) of visiting a prairie garden in Illinois after seventeen inches of rain had fallen the previous day and a natural disaster had been declared.  Her host’s garden “was perky and standing tall … I cannot imagine a more fitting tribute to the strength and resilience of the prairie. While all around us conventional plantings of suburban yards were gasping for life support, the prairie plants were saying, Catastrophe?  We’re built for catastrophe!”

Paul says native plants can provide interest from April to November.  He prefers to tailor plantings to their sites, advising us not to amend planting areas and to work with the soil we have.  Your soil type can be determined by stirring a trowelful in a Mason jar filled with water and observing the layers which form in a day or two.  Soil containing lots of sand will drain quickly; clay-heavy soils will hold moisture.  He showed us a garden he’d created for a client using the lasagna-bed method we learned about in August.  Mulch from Hydro One (for which he pays in beer!) tops the bed, which is allowed to settle for six months before planting.  Paul collects seeds in the wild with care: he never takes more than five percent of the seeds of one species, collects from large populations to ensure diversity, and doesn’t harm the sites, choosing to harvest pitcher plant seeds in winter when the ground is frozen rather than disturb their bog home.  He explained the different germination patterns of native seeds: some require a period of four to twenty weeks in moist soil or peat in the fridge and some need warm moist treatment before the cold period.  Some seeds with hard coats must be scarified with sandpaper; Paul lines a coffee can with it, puts in some good music, and shakes away!  Patience is a virtue, too: some plants such as lilies and trilliums can take seven years between seeding and flowering. He told us about lupine seeds which germinated after ten thousand years! He sprinkles most seed on the surface of an indoor sterilized potting mix. Some seeds can be germinated outdoors on peat or sand.

Paul then took us through a photo gallery of some of his favourites, starting in spring with skunk cabbage, a wetland plant which can raise the temperature around its roots enough to melt snow and which attracts carrion flies with its distinctive odour.  The flies travel from flower to flower, seeking the rotting meat they think is nearby, and pollinate the plants.  “Glad I’m human,” said Paul. 

Paul showed us ephemeral woodland plants such as trout lilies and trilliums, which complete their annual cycles in only eight weeks before the trees leaf out and then retreat underground, and longer-lasting favourites like bloodroot, mayapple, and wild ginger.  He was once asked if wild ginger is edible.  “Anything’s edible once!” he said cheerfully.  He explained that in dry years, Jack-in-the-pulpit plants are male, waiting for moister years to produce seed.  “Men are cheap!” he said. Sawflies from Europe are now plaguing the leaves of the lovely columbine. Hot sauce, he’s been told, might be the answer. Paul loves ferns: there are 35 to 40 varieties in Ontario.

Summer sees sun-loving plants in the spotlight.  Beardtongue is one of Paul’s favourites.  Black-eyed Susan, he says, can behave like an annual and bloom itself nearly to death.  Cardinal flower in wet soil and blue lobelia in drier conditions provide red and blue flowers for hummingbirds.  Paul likes Campanula rotundifolia, the delicate bellflower, but not the non-native creeping bellflower, a weedy plant he’s been trying to kill for 25 years. “What an incredible plant,” he said sarcasm dripping from his voice. He spoke of seeing frogs and mice trapped by carnivorous plants: “It’s a cruel world!”

Joe Pye weed, asters, bottle gentians, goldenrod, and sneezeweed (Who wants to buy a plant called sneezeweed?” he lamented) help the native garden shine well into fall.  Paul recommends smooth rose (native roses are single and good for pollinators), fragrant sumac, red and silky dogwood, serviceberry, and potentilla to gardeners looking for native shrubs.  Trees worth growing (as the saying goes, the best time to plant a tree was twenty years ago; the second-best time to plant is now) include hackberries, black and sugar maples, white oaks, butternuts, cedars, black cherries, and the rock stars of the tree world, birches (“They grow fast and die young”). An oak cored in Toronto was found to be 550 years old!

Paul included a section on invasive plants at the end of his talk which gave us some idea of the scale of the problem. The beetle brought to Canada to eat loosestrife now seems to be eating native plants.  Monarch butterflies are confused by dog-strangling vine, a member of the same plant genus as milkweed, and will lay their eggs on it; these eggs don’t survive.  Garlic mustard is able to colonize shaded forest areas.  Goutweed seems nearly indestructible: Paul saw it spread by the roots under heavy layers of cardboard to pop up eight feet away.  He wants Norway maple dead, not alive.  He once showed pictures of buckthorn during a talk and a woman asked him, “Isn’t that chokecherry?  I made jam from the berries for my whole family!” The Latin for buckthorn, Rhamnus cathartic, means laxative he had to tell her.  What do you do about periwinkle? he was asked.  “Move” he said.  

Paul explained that he started to search for alternatives to these and other invasive plants and discovered the world of native flora.  His research led from hobby to study to business opportunity and he’s been sharing his knowledge ever since.  After Barbara Hewton thanked him for his talk, he said, “A hundred members, a TV, AND I get a mug?  This could be the best horticultural society ever!”