Perennials You Must Plant This Fall
It seems many people hate to see summer end, but I don’t! Why would anyone like a season filled with seemingly endless watering and weeding while sweat runs into your eyes, battling insects that try to suck your blood? I joke that I go to the house in June to lie down and wait for autumn, my favorite time of year.
Glorious fall foliage color is a given, but this is also a time to enjoy a number of easily grown perennials – plants that live for more than two years – that paint bold hues on the cooling landscape.
Goldenrods: Not to Blame for Allergies
Don’t sneeze at me for praising goldenrod! It’s been unfairly blamed for provoking pollen-related allergies. The fact is that goldenrod pollen is heavy, sticky pollen that does not blow easily in the wind – it has to be transported by insects. Beekeepers know this and consider it a valuable plant for building up winter reserves in the hives. Ragweed is the true culprit. Its nondescript, unnoticed flowers produce copious amounts of windblown pollen at the same time goldenrod blooms, and often in the same fields.
Perennial Planting Tips
So, speak up and defend them, but do be particular in selecting garden-appropriate forms, as some spread far too aggressively. It should be obvious that one to avoid is the common form (Solidago Canadensis) that fills overgrown meadows. Sure, it makes a lovely sea of gold there, but there it should remain.
You can find more mannerly varieties of goldenrod such as “Fireworks,” which won the Award of Garden Merit from the Royal Horticultural Society. Interestingly, American native plants are frequently more valued in England than at home. Other recommendations include “Little Lemon” and “Golden Fleece.”
Get the Blues with Aster and Salvia
What looks gorgeous contrasting with goldenrod’s yellow? Blue and purple flowers, of course, and the natural world must agree. One of the loveliest blue asters with similar bloom time is aromatic aster (Symphyotrichum oblongifolium), which forms a billowing, flowery mound that shows off well into November. A permanent label will help this plant survive in your garden, as its nondescript appearance in spring and early summer may cause it to be mistaken for a weed – and yes, I am speaking from personal experience. Be sure to give this aster a generous piece of ground, as it can spread several feet wide, though remaining a tidy mat just a couple of feet tall. The aforementioned aroma comes from the foliage when crushed.
Salvia-philes love to stroke the velvety deep purple flowers of Mexican bush sage (Salvia leucantha). Its perennial status can be debatable in colder parts of Tennessee, though planting in soil that remains very well drained even during cold, rainy winters helps with success. This salvia can be found in solid purple or bicolored white and purple forms. Blooming starts in October, and flowering spikes continue to stretch skyward with fresh, flowering buds until frost stops the show.
Think Pink with Muhly Grass
Perennial grasses add movement and grace to the autumn tableau. Please note that many forms of maiden grass (Miscanthus sinensis) reseed aggressively and should be avoided, but some cultivars have proven to be law-abiding garden citizens. “Adagio” and “Morning Light” are among them, but if you’d like to use a native, pink muhly grass (Muhlenbergia capillaris) would be a winning choice.
Summon your patience. Muhly grass should be planted in the spring for best results, and through summer, it offers little more than a shock of thin, blue-green foliage. Flowering stems emerge late in the growing season. Grass flowers lack petals, so while individual flowers are tiny and unremarkable, the sheer numbers of them (followed by minuscule seeds) create the show-stopping opalescent gauze of pink. There are not many plants more spectacular when backlit by early or setting sun, so site it accordingly.
Don’t Forget Old Standbys
Newer plants tend to attract avid gardeners, but old standbys have earned their place, and few have proven durability as well as the venerable “Autumn Joy” sedum. Yes, there are new forms with colorful foliage and forms with brighter flowers, but I like the reliable sturdiness of this old form. Be sure not to cut it back when flowering is finished, as the flat head of dried flowers is winter interest, at its best when capped with fresh snow.