At least with all the recent wet weather September should begin with nicely moist, hopefully not waterlogged, soil conditions. This should make any digging, replanting and, most timely, bulb planting much easier. Bulb catalogues will have been out for some time now so the keen gardener should already have got his / her order in. Of course, in these days of instant gratification, it’s very easy to go online to do your bulb research and ordering so there’s still plenty of time to get it done.
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 ‘six feet under’ but a great bruiser of a daffodil bulb needs to be at least a trowel’s depth down. Take time over planting and remember to chuck a generous fistful of ‘fish, blood and bone’ 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 so any spot in the garden could become home to a bulbous perennial to add interest when, perhaps, previously there was none. Be adventurous and generous with them.
One of the most successful bulb plantings I ever did was a huge ‘pool’ of blue Scilla sibirica (squills) and Anemone blanda ‘White Splendour’ under the canopy of a big old beech. I had to plant around 3,000 by broadcasting a few hundred at a time and planting them, very quickly with the stab of a narrow trowel, where they fell. It took less than a day but I did get blisters on my trowel stabbing hand!
Assuming you can fit in other gardening chores, around all the bulb planting, this month is your last chance for using herbicides, like glyphosate (‘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 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 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. Whilst you’ve got your secateurs handy you might want to reduce the height of plants such as Buddleia which might also suffer wind damage.
In borders clump forming herbaceous perennials can be dug up and divided to fill larger areas, or to pot up then give away. Some can be divided by hand, some may respond to the old ‘back-to-back fork’ method while others only succumb to a well aimed spade. My favourite implement, when precise sectioning is required, is an old bread knife or, for bigger stuff, a hand saw.
Winter bedding plants will get a head start and establish better if planted out into their final positions before temperatures start to drop. Similarly, autumn lawn care operations need to be done now while the grass is still growing actively enough to bounce back having been subjected to concoctions such as ‘weed and feed’.
Due the recent wet weather I am behind with cutting my hedges so getting this finished is now a priority. September really is the last chance to tackle them and still leave time for them to recover properly before winter.
All in all September is a really positive month. It’s nice when we get one of those late returns of properly warm, summer, weather but, equally, I don’t begrudge the cool wetness. It encourages all the autumn flowering plants, especially the bulbs, to put on a good display which makes the garden come alive again.