Oops we goofed
Garden Clippings for Dec 23, 2023
Oops, we goofed.
Periodically the horticulture industry makes a mistake. Sort of like lemons in the auto industry. Nothing critical and not immediate, but a few years after a new model is introduced, it becomes evident that what was once popular is actually a flop.
Thirty and forty years ago, the 2 most popular plants in our nursery were Euonymus Gaiety (Euonymus fortuneii ‘Gaiety’) and Purple Leaf Plum (Prunus ‘Cistena’). We couldn’t grow them fast enough and gardeners could not snap them up quickly enough.
Euonymus Gaiety was valued for its unique leaves, variegated in green and white. The plant did not grow fast, and was an easy care compact broadleaved evergreen. If planted against a fence or wall, it grew mildly into a vine.
But after a few decades, after most gardeners had at least a few Euonymus in their landscapes, a crawling insect known as Euonymus Scale put an end to the trend.
The Purple Leaf Sandcherry story is similar. Bright purple leaves and delightful pink flowers in spring brought Purple Leaf Plum instant popularity. A few decades later, Purple Leaf Plum succumbed to a lineup of bacteria and fungus, resulting in a tailspin.
In the sixties and seventies, Norway Maple (Acer platanoides) was almost touted as a miracle shade tree. It was prized for its willingness to grow in challenging urban environments where air pollution and poor soil was the norm. Norway Maples transplanted easily, cast dense shade, and grew into a perfect, predictable shape.
Fast forward a few decades and we began to question our affection for Norway Maples. Their aggressive roots made life challenging for anything growing in its shade. Birds would fly a detour around Norway Maples because they were not wildlife friendly. Baby Norway Maples began to appear at the edge of woodlots and in other unexpected places because those cute helicopter seeds managed to sprout.
By the year 2000, several jurisdictions added Norway Maples to their invasive species list. While there are still countless Norway Maples lining the city streets, we are slowly seeing their demise, aided by fungus and bacteria such as Anthracnose, Tar Spot and Verticillium Wilt.
Not long ago, Austrian Pine (Pinus nigra) was one of our most popular evergreen trees. It was widely planted in City parks, shopping plazas, and along highways because it was tough as nails and tolerant of nasty City conditions such as pollution and salt spray. But Austrian Pine soon grew too large for small City lots, and its heavy texture caused it to fall out of favour. Today, Needle Blight fungus is slowly causing Austrian Pine to be removed from the landscape.
It appears Colorado Spruce (Picea pungens) is following the footsteps of Austrian Pine. A majestic tree, prized for its blue colour and tall pyramidal shape, Colorado Spruce is becoming increasingly susceptible to Needle Cast, causing the tree to slowly lose its appeal. New varieties of Colorado Spruce appear to be resistant to the disease.
The jury is out on Flowering Pear (Pyrus Calleryana). A small growing highly ornamental tree, Flowering Pear quickly climbed the popularity ladder for its compact size, lovely white flowers and attractive shiny green foliage. But in the last few years, jurisdictions south of the border have begun to challenge Flowering Pear’s value, primarily because the once-innocent tree found the ability to cross-breed with native pear trees. And their fragrance at blooming time was questionable.
It would be nice to know if a certain tree variety would eventually become a lemon. Gardeners can rest assured that all trees do their part to improve the environment by cleaning the air, providing shade, blocking wind, and providing homes for animals. Do your research to ensure you select the right tree for your location. And consider planting native trees which may have better insect and disease resistance.