IT'S still summer in my mind and I'm going to enjoy all the beauty the garden provides before I start any garden renovations.
That doesn't mean there isn't work to do. There's always work in the garden, but it makes no sense to tear the garden apart at the peak of its beauty just to satisfy some rules. And so with those thoughts in mind, it's time for a late summer garden myth buster.
- Gardening myth: Divide and transplant in September.
On the West Coast our warmest soil temperature occurs in September through October and sometimes into late November depending on how much rain we receive.
Now is an excellent time to plant most hardy trees, shrubs and perennials from a pot into the ground, which allows enough time for establishment before winter.
But it's still a little warm to transplant perennials and shrubs or to plant spring flowering bulbs. It's not that plants cannot be transplanted in September it's just difficult to keep transplants adequately watered during late summer heat.
As a matter of fact, some spring flowering bulbs prefer cooler soil temperatures found in late October to grow roots. Tulips, for example, do not like growing in the warm, dry soil found in September during an Indian summer, so wait for October to plant those bulbs.
As for dividing perennials now, why would anyone rip apart beautiful hostas, rudbeckia or any other perennial in September when those plants look so fabulous? Wait to divide perennials until they have retracted their green leaf energy and divide them when there is little impact on the garden's presentation.
Some plants can be transplanted during the warm soil temperatures of fall, but some plants do not respond well to fall planting or transplanting. These include some roses, most woody subshrubs like Russian sage, some clematis, most Mediterraneanorigin plants and plants that have marginal hardiness in our region like fan palms, bananas, and gunnera.
- Gardening myth: Prune trees and shrubs in September.
September is not the best time to prune many plants.
For example, hydrangeas should not be pruned before winter. Instead, prune hydrangeas in March after the winter frost has passed. Leave your hydrangeas unpruned and enjoy their lovely flower heads for winter interest in the garden. There are also many spring flowering shrubs like forsythia, rhododendron and camellia that grow and set their flower buds during late summer, so pruning those shrubs now would remove spring flowers.
While it is true that hedges can be pruned now, hedges must not be pruned hard at this time or the resulting new growth and newly exposed foliage may not harden before winter arrives and therefore may suffer frost burn. Just give the hedge a light trim to tidy it up, but spare the whip and be gentle during fall hedge pruning, applying some restraint in anticipation of the cold winter ahead.
As for tree pruning, it is not advisable to prune heavily any tree that is entering dormancy because pruning removes leaf surface area and therefore removes the food reserves found in the leaves.
If the work can be postponed until winter dormancy or the next summer pruning period, then do so. If you simply cannot wait due to obstacle entanglement, construction schedules or whatever else is pushing the schedule, then prune but prune properly using clean tools and remove the minimum amount of foliage possible.
- Gardening myth: Bring in tender plants in September.
Some people recommend starting in September potting down and bringing tender plants indoors to overwinter.
If you have a large garden full of many tenders that you overwinter indoors then perhaps you have to start now just to stay on schedule. However, unless you have multi-dozens of tender plants, there is no point tearing apart the garden or container displays during the September's peak display season, there is plenty of time to do such work in October.
Since we live in a reasonably mild, oceaninfluenced climate here on the West Coast, we enjoy the luxury of a long gardening season that starts in February and ends in early December.
We are truly blessed with a great climate that allows us to garden most of the year, through the heat and rain.
We tend to be rushed by proactive marketing into undertaking the next gardening chore, big trend or whatever is being pushed by someone's agenda. Don't be rushed into tearing the garden apart in September in preparation for winter, there's plenty of time left ahead.
September is a season of beautifully textured grasses, bright pink sedums, bold yellow rudbeckia, purple asters, brilliant scarlet reds colouring our trees and shrubs and a late summer that lingers into October.
Todd Major is a journeyman horticulturist, garden designer, writer, consultant and organic advocate. For advice contact him at [email protected]
