I know it’s a bit depressing to have to admit that the summer is drawing to a close, with autumn waiting in the wings, but it does signal a new period of activity in the garden.
Before the advent of container grown plants, chiefly driven by the introduction of plastic pots and peat based composts, autumn was the most important planting time. This is because plants are still active enough to produce new roots, if dug up, divided, and moved to a new position, while lower temperatures and increased rainfall increases their chances of successful establishment.
The same conditions also give spring flowering bulbs the best start into growth when they break dormancy once planted in the soil. There are few things in gardening as worthwhile as planting spring flowering bulbs because they are a guaranteed source of blooming joy wherever you can squeeze a few in.
Except for tulips, which should be planted into November to avoid ‘tulip fire’, the vast majority of bulb types are better off in the ground sooner rather than later. This is because the less time they spend out of the soil, having been dug up from their nursery fields, the better. They want to be sending roots out into garden soil while it is still warm. That way they can get properly established before the winter cold slows everything down. If you need to prioritise your planting then it’s a good idea to plant them in flowering order; the earliest little Iris histrioides, needs to be in the ground now whilst much later flowering Narcissi can safely be left for a bit.
When planting the general rule is that each bulb should be covered by soil to a depth of two to three times the size of the bulb itself. Common sense tells you that a tiny crocus bulb, say, will struggle if you plant it as if burying a corpse but a stonking great daffodil bulb needs to be at least a trowel’s depth down. Take time over planting and remember to chuck a generous fistful of general purpose fertiliser over the bulb planting area.
Only your imagination will limit the possibilities of where you can put bulbs – their myriad species have evolved to fit almost any situation; in beds amongst shrubs, in containers full of winter bedding, pushing up through turf, in full sun, half shade, deep shade…. you get the idea. A quick browse through a bulb catalogue, most conveniently ‘online’ these days, will generate so many possibilities that you are bound to get ‘kid in a sweetshop’ syndrome!
Assuming you can fit in other gardening chores, around all the bulb planting, this month is your last chance for using herbicides, like gyphosate (‘Round Up’), which relies on weeds being in active growth. Treating neglected areas now can be especially effective because there are fewer weed seeds floating around, at this time of year, so cleared areas stay cleaner for longer. This is particularly crucial if you need to kill off turf where you are planning to dig new beds over in the winter. An organic alternative is to cover these areas with light excluding mulch, whatever you can lay your hands on, and then wait a few months for the grass to starve to death.
Another timely task is the tying in of long growths on climbers, roses especially, so that they don’t get snapped off in windy weather and because they are more biddable while relatively young. The general rule is to replace each old, flowered, stem with a vigorous new one from the current season’s growth. As with all rules ‘once you know them they can be broken’ which is handy because no rose is likely to have read the pruning handbook and will not behave impeccably.
Just deal with it the best you can whilst keeping in mind that, at the end of the day, you want to have a good covering of rose with as much tied in securely as possible, as few main stems crossing as you can manage and a good balance of old and new growth; good luck with that.
It’s getting a bit late for cuttings from tender perennials (see last month) as they should really be taken before the weather turns cooler. Having said that, if you’ve not taken any yet and want some ‘winter insurance’ against the parent plants dying, then cuttings can be taken from species such as Argyranthemum, Fuchsia, Pelargonium, Penstemon, and Verbena. The most tender perennials which you may have used in containers or hanging baskets can be dug up, trimmed back (roots and top growth) and potted up for overwintering in a light, frost-free, position.
Autumn lawn care operations need to be done now while the grass is still growing actively enough to recover once subjected to a ‘weed and feed’ type preparation. Only use those products designed for late season use as more general lawn treatments may contain too much nitrogenous fertiliser and you don’t want to be encouraging too much leafy growth at this time of year.
Last month I mentioned that yew hedges are traditionally cut in August but it’s still not too late to do them. They only need cutting once a year, a blessing, and they are done now because they will have done practically all of their growing yet will still have time to toughen up before the serious frosts.
I tend to tackle a lot of hedge cutting now, into winter, as birds have stopped nesting and because it’s pleasing to have neat looking hedges as a foil to everything else dying down or denuding. My mixed hedges, around the field, get left longer as they are full of rose hips, nuts and berries which are invaluable for all the wildlife that needs to put on fat reserves for the winter ahead (I know how they feel).
As you can see, there’s lots to be doing in the garden right now—especially this year when everything seems to have ‘grown like Topsy’.