There is a touch of fall in the air as brisk breezes abruptly whisked away a few days of muggy summertime warmth and humidity creating a sense of urgency to perform a wide array of landscaping activities. Although this past spring offered unprecedented warmth and phenomenal growing conditions, typical New England springs often feature cold, soggy soils and unpredictable weather conditions that pose many challenges for homeowners with lengthy lists of gardening chores. The warm days and cool evenings of September offer an ideal opportunity to get a head start on many of these gardening projects, while warm, workable soils and reliable moisture make the fall season often the best time to renovate lawns, prepare new gardens, divide and transplant perennials, and plant bulbs, trees, and shrubs.
My first priority each September is to stroll through the landscape with my notebook and camera to document the fall garden while critically viewing and analyzing my lawn, gardens, and shrubbery. I try to imagine an ideal world with unlimited time, energy, and resources to perfect my surroundings. Digital images are snapped of my perennial borders to remind me of the mature size of my perennials at season’s end to avoid over-planting during the spring season when there appears to be so much empty space between the plants.
Light exposure in all gardens is also recorded several times during the day as the availability of sunlight changes each year as trees and shrubs mature affecting the performance of many plants. Some sun-loving perennials may require relocation to brighter locales to ensure better performance, although thinning-out or limbing-up trees may resolve low light issues. Light pruning of some trees and shrubs will be done this fall, but major pruning of trees will be performed in early spring when their architecture is easier to view. Transplanting of deciduous trees and shrubs will be delayed until their leaves drop later this season.
My notebook quickly fills with long lists of changes to be made, trees and shrubs that require pruning, and perennials that should be divided, transplanted, or eliminated. Once my initial list is generated, I attempt to prioritize the projects knowing that the list will continue to grow exponentially each time I walk through the garden.
High on the priority list is caring for my tender plants. Although frosts are unlikely until October, innumerable tropical plants, houseplants, and annuals are sensitive to temperatures even in the forties. Coleus plants are particularly vulnerable to cool temperatures and during the coming week, I plan to take tip cuttings from these colorful annuals, dip them in rooting powder and insert them into pots of perlite. In a few weeks, rooted cuttings will be transplanted into containers of potting soil and grown in a warm, bright location through the winter months. Houseplants that enjoyed the summer outdoors should be gradually acclimated to the lower light conditions they will encounter in your home environment. Even houseplants that spent the summer in the shade received much brighter light than they are likely to find indoors. If these plants can be moved into a sunroom or porch prior to the threat of frost, the gradual reduction in light will be less of a shock, although nearly all plants experience some leaf-drop or dieback as they adjust to lower light and humidity in our dry, heated indoor spaces.
Before bringing any plant indoors, closely inspect cuttings and houseplants for pests. Somehow insects seem to know which plants are destined for a warm, cozy winter indoors. Many often go unnoticed for weeks while sucking the vitality out of our plants. Although no insects may be readily observed, eggs laid on the foliage may hatch once the plants are brought into warmer environments. One or two applications of a light horticultural oil spray, a safe, odorless pesticide that works by suffocation, will eliminate a large percentage of the typical intruders including aphids, scale, mealy bugs, white flies, and spider mites. For long-term systemic insect control, consider spraying with Bayer Rose and Flower. Be sure to check the drainage holes of the containers for sow bugs, worms, and slugs or you may discover them crawling across the floors of your home.
September is the preferred time of year to install or renovate lawns. Warm soil temperatures facilitate the prompt germination of grass seed without interference from a profusion of weed seed sprouts and Mother Nature usually assists with the important task of providing consistent moisture. This is an ideal time to treat persistent weeds, patch bare spots, remove thatch, aerate, overseed, spread lime, and fertilize. Established lawns tend to develop thatch, an interwoven layer of dead grass plants (not grass clippings) between the soil and green growth. A thin layer of thatch helps conserve moisture and nutrients, but when thatch exceeds a half inch, it reduces the ability of grass plants to secure moisture and nutrients. Vigorous raking may remove light thatch, but a large or neglected lawn may require heavier equipment to extricate a dense layer of matted dead grass plants. Older lawns also benefit from core aeration, especially in areas compacted by heavy traffic.
Weeding gardens should also be a priority, especially the removal of seed-laden intruders like crabgrass. The soft, damp earth offers an ideal opportunity to extricate tap-rooted dandelion and pokeweed sprouts and other misplaced wildflowers lurking beneath the drooping foliage of declining perennials where they are secretly dispersing their seeds. A few minutes each day will save hours of weeding next spring.
As dusk approached on a cool, crisp September eve, heaps of weeds and crabgrass quickly filled my tarp, dramatically improving the overall appearance of the garden and providing a wonderful sense of accomplishment.
Suzanne Mahler is an avid gardener, photographer and lecturer who has been developing the 1.5-acre property surrounding her home in Hanover for more than 30 years. Her weekly gardening column Green Thumbs Up has appeared in GateHouse Media New England newspapers for more than a decade. She is a member of two local garden clubs, past president of the New England Daylily Society, and an overseer for the Massachusetts Horticultural Society, and she is employed at two garden centers.
