What’s Wrong With My Forsythia?

Some time ago my wife, Joan, and I were given a private tour of a lovely multi-flower-bedded homescape with an expansive and beautiful layout. On the border of the neighboring property, there was a forsythia hedge, whose normally dense branches act as a privacy border. However the hedge was spindly, its yellow spring flowers were sparse, appearing as nutrient-deficient or diseased. The caveat here is a good part of the hedge was growing under an over-story of native Black Walnut trees. Native, meaning it was growing naturally in North America, whereas forsythia is an alien species introduced from Asia. Forsythia is popular for its early yellow flowers that boldly proclaim winter is over. It’s pretty, but it spreads by leap-frogging its branches into the ground, creating its own root system and creating another bush. Forsythia will take over an entire yard if permitted. As such, it’s called invasive. Birds will nest in it for protection but it provides no food source for our winged friends (*pg. 283). Black Walnut (Juglans nigro) is an excellent wildlife tree because its foliage can host up to 100 species of insects for native birds (*pg. 192). Juglans also produce large nuts that sustain squirrels and other rodents through the winter. The reason non-native plants fare poorly under walnut trees is that the husks of the nuts themselves produce juglone, a chemical that can stunt growth or kill other plants. Alien ornamentals like forsythia are the most sensitive because they have no original growth experience with this North American species. If one wishes to promote healthy bird and insect populations, you could consider native plantings that are not affected by the walnut alleochemicals (*pg. 192).

Al Freeman

*I highly recommend Douglas Tallamy’s book “Bringing Nature Home” from Timber Press if you want to know how you can sustain wildlife with native plants.

People who visit our gardens always ask how we keep up with all of them. It’s simple. We make mistakes. We learn from them. We surrender, acquiescing to nature and to the nature of plants, the hum of winged wildlife testifying to their health.

The forsythia was one of the first things planted, prior to my understanding of the roles native and foreign plants play in the landscape.  We thought it was indestructible – and it was, for 35 years, serving its purpose as an impenetrable screen, “the great green wall” greeting us in early spring — until the black walnut trees sprouted, grew and produced nuts. Last winter, the area also flooded, and when we asked promoter of native plants, Wayne Paquette of Quackin’ Grass, if this condition contributed to its demise, he reminded us that you don’t find forsythia in lowlands. Either way, what we thought was imperishable, wasn’t. After ripping the hapless plants from the area, we replaced them with water loving natives — shrub dogwoods and swamp maples. Another area prone to seasonal flooding experienced more than the lilacs could endure this year. I mourn the loss of the fragrant, lavender and plum purple racemes that formed a grove for thirty years, yet I’m not replanting them. Instead I’ve replaced them with willows. Wherever water collects we’ve planted willows – though not the weeping type notorious for its greedy roots – and they happily drink the puddles.

Our lawn contains several examples of nature altering our plans. A non-invasive bamboo that behaved itself for 12 years, a solitary sprout in a sea of lady’s mantle and evening primrose, became rampant one year, galloping to form a field of chartreuse and golden blades, beautiful beneath the native witch hazel, pussy willow, and shrub dogwood. Spiraea threatens to consume most of another garden, yet with its leaves emerging scarlet, orange, and gold, greening in summer for its display of pale pink to deep raspberry saucers, and igniting again in autumn, this native, coupled with the bronzed smoke tree, provides sufficient interest. The character of the rock garden has changed throughout the course of its existence. Initially, it resembled a pastel quilt with its collection of alpines and ruffle of Johnny-jump-ups, which seeded themselves into a velvety purple carpet the second year, and in the third, leapt into the lawn. Magenta mounds of geranium ‘Sanguine’ rapidly multiplied, and several thymes stitched themselves across the soil. Last year, the heather spread through a third of the garden; with its soft, silver and lavender bristles — that’s all right.

I’m no longer the purist I once was, strictly enforcing the color schemes I planned. I bend the rules now. I haven’t the heart to rip the pale pink phlox from the monochromatic moon garden, or the rose purchased as white, realizing that this crimson one echoes the filly throat of the peony “Festiva Maxima”. The mixture of white, pink, purple and red phloxes have produced myriad shades, and we look forward to the surprise of their assortment. Similarly, white, pink and blue balloon flowers have swapped seeds to supply interesting purples, varieties of Siberian irises have generated blossoms almost white to nearly black, and pink and purple asters have influenced the hues of one another to create flowers of pale pink, raspberry and fuschia, violet, lavender, wine, plum and grape.

We’ve always welcomed native plants. We cultivate blueberries for their fruit and foliage, retain the blackberry and raspberry canes wherever they crop up, and appreciate the elderberries the birds propagate, and nest in, near windows. We purchased a ‘Kousa’ dogwood one year, and the following spring it revealed itself as something else – a native variety. I initially contemplated a complaint, yet shortly after the honey bees fell in love with it, we did too, favoring the buttery blooms over the ivory bracts of the cultivar. We also encourage wildflowers to remain. The daisies sprinkled along the stepping stones to our kitchen door, the Queen Anne’s lace, a veil in a garden of pastels, the milkweed that found a niche in the thyme lawn to beckon the butterflies, all helped to persuade us of the value of native flowers. This year’s drought furthered that wisdom. While stalwart perennials withered, supplying small, sparse, brief blossoms, arches of golden rod, towering Joe Pye weed, and clouds of wild asters, and their swarming insects, flourished.

This year served to remind everyone that nature is in charge, not us. All our plans are for naught in the face of a severe drought, storm, or virus. And New England’s fall never fails to remind us of its artistry. We visited Trailwood recently and viewed, through the stoic cattails and wisps of wild wheat, the blaze of colors from the maples’ flames reflected in the surface of the black water. None of it planned. All of it perfect.