With fall comes the debate: should one cut off the tops of all the perennials or leave them intact for the winter.
Neither method is right or wrong; both ways of gardening have pluses and minuses.
If the foliage is removed, the garden looks neat and tidy. Come spring the garden is ready to grow without worrying about letting the soil dry out before cutting back the foliage.
Removing foliage includes all seed heads which makes for less weeding next season as most of the volunteer plants are eliminated.
Lack of foliage makes it easier to detect weeds that will continue to grow and spread until the ground freezes. Clean gardens are easy to top dress as materials can be spread through out the garden using a rake.
Once the snow falls a clean garden will blend into the winter landscape. There may be a slight variation around the edge of the bed depending on what materials are used to define it.
Gardeners that leave the tops on their perennials will have different shapes and colours to view until the garden is covered with snow.
As the tops of the plants die down they provide extra insulation for the perennial plants. This is very important in years when the snow is late arriving.
The foliage and seed heads can attract rodents. They find the foliage cozy and the seeds are an excellent food source.
One rodent in a garden can do a massive amount of damage during the winter months.
Once the snow has fallen, shapes and shadows will form until the snow is deep enough to render the landscape smooth. Even then there are usually a few tall stems left to create shape and shadows in the winter garden.
Come spring, the perennial bed will need to be cleaned and all the old foliage removed. This task can seem like less work in the spring as it is great to be outside after a long winter.
Spring and fall are both good times to amend the soil. If it wasn’t done in the fall, cover the ground with a centimeter of compost or well-rotted manure should be done in the spring.
Perennials can be split either in the fall or spring. In the fall the plants are easy to find and identify in the garden. Their size is evident from the amount of foliage that is present.
Knowing the size of existing plants makes it easier to space and size plants, thus balancing the garden.
Fall splitting also makes sense for plants that are slow to emerge in the spring. Often the rest of the garden is lush making it hard to dig and move late emerging plants.
Moving the plants before the end of September allows the plants to put down roots and anchor themselves into surrounding soil. Plants that are moved later in the year should be planted slightly deeper than usual to avoid damage from frost heaves.
When splitting a plant in spring it is easy to discard parts of the plant that died over winter. When the plant is split in the fall one must always believe that the complete plant will survive.
Ground covers or low growing plants usually have shallow roots and rarely do well when transplanted in the fall. These plants do best when moved in the spring when they are actively growing and putting down new roots.
The choice of what garden work is done and when is very individual. Take into account the time available in each season.
Linda Tomlinson is a horticulturist and educator living in Rocky Mountain House. You can contact her at firstname.lastname@example.org