September in the Garden

Even though, at the time of writing, thunderstorms are forecast for the next few days there is no escaping the fact that it’s been an unusually hot, dry, summer. This will affect your gardening activities this month and into the future. Here, in the south west, we are generally a little wetter and cooler, than the south east, which at least means that we tend to escape hosepipe bans so that essential irrigation, of your most precious plants, should have been possible. Hopefully this means that you still have a garden to maintain, despite the drought, now that we are heading into autumn and, fingers crossed, increased rainfall.
The biggest effect of the hot, dry, summer is that it will have stressed many plants so that a lot of them will have flowered earlier than normal and for a shorter period. Some of the late flowering perennials, that can usually be relied upon to keep flower borders looking good well into the autumn, have flowered in august and will need a good dollop of rain if they are to soldier on much longer. The tribe of plants that I am thinking of are the ‘daisies’; Rudbeckia, Helenium, Helianthus, Echinacea, asters (now mostly reclassified as Symphyotrichum) etc.
Dead-heading, cutting back and adding extra support is more important than ever if your garden is to look as good as it can, especially when heavy rain beats down plants that have been weakened by severe lack of water. Some plants which are generally pretty immune to collapse in dry conditions, such as Persicaria and Crocosmia, have succumbed this year but will bounce back once we’ve had a bit of rain. The increase in the number of named cultivars of Persicaria amplexicaulis, over the last couple of decades, reflects a shift towards the more naturalistic, late summer flowering, planting style that also includes all those stalwarts of long lasting border plantings; Miscanthus (giant grasses) in its myriad forms. Miscanthus are one genus that actually thrives in a hot summer and will flower at its best in hot conditions, especially in heavier soils where it can eek out the available soil water content.
Schizostylis, now known as Hesperantha, hit their flowering stride after the heat of the summer has given way to more autumnal conditions and add a really fresh burst of colour, especially in the cultivar Hesperantha coccinea ‘Major’, akin to spring flowering bulbs. The caveat here is that, like many garden plants that hail from South Africa, they prefer to have heat and soil moisture if they are to thrive. They naturally flower in the Southern Hemisphere spring, like many of our autumn flowering bulbs, corms and rhizomes, and grow in stream side locations where, in that hotter climate, they even survive permanently wet soil. In the UK climate, ‘normal’ garden soil is fine although Hesperantha definitely prefers soil where it gets full sun, which never completely dries out, and which is not waterlogged in our cold winters—not always an easy conditions list to provide.
Talking of ‘spring like’ plants reminds me that we are heading into peak bulb planting season. This is a subject I’ve covered numerous times before so this is just a timely reminder that, as soon as soil conditions allow, it’s important to buy and plants your spring flowering bulbs. As ever, the exception to the general rule of thumb, getting them into the ground roughly in flowering order, is that tulips should be ordered now, while stocks last, but planting should be delayed until November for cultural reasons. While browsing for spring flowering bulbs why not take a look at some of the autumn flowering species, such as Colchicums and autumn flowering Crocus, which are the kind of special garden plants to add a fillip of interest to a planting scheme or container?
I didn’t do much hedge cutting in August. It’s not the kind of activity that lends itself to uncomfortably hot, dry conditions where the hedge you are cutting is already stressed, by lack of water, and may just scorch if you remove its outer layer of foliage in the blazing sun. Hopefully we’ll have better hedge cutting weather this month which will allow me to catch up with essential maintenance activities. The added bonus is that neatening up the structural elements of the garden really helps to keep it looking fresh and reinvigorated right up until everything begins to die back.
The formal lawn is the other element of the garden, aside from neatly clipped hedging and topiary, which really offsets everything else. This will have turned brown during the drought conditions, because watering lawns is a ‘no-no’, but early autumn is a good time to give is some ‘tlc’ and help it to recover from the stresses of a being droughted. Once we’ve had some decent spells of rain and you can see that the grass is growing again, turning green, it’s a good idea to give it a gentle raking with a wire lawn rake, to remove any dead stems, thatch and moss. A powered scarifier may prove a little too brutal, on a stressed lawn, and could lead to unsightly areas of bare soil which will require total reseeding if it’s to recover.
A gentle rake over, mowing at an increased height once the sward starts to recover, plus the addition of a proprietary ‘weed and feed’, will return your lawn to health before it has to endure winter weather. If the lawn is not huge, and it really has suffered badly, then early autumn is a good time to resow it, well before any frosts are likely, or to ‘over sow’ it using a top dressing of sieved top soil with your chosen grass seed mixed into it. The ‘top dressing’ of fine lawns is the kind of gardening activity that used to be common practice but which is now confined to the realms of the green keeper or lawn fanatic. These days, spiking lawns, rolling them and cutting them solely with a cylinder mower are the kind of time consuming tasks that have fallen by the wayside—perhaps it’s time to give your lawn a bit of love again?
Lawns and meadows are not the same thing! Simply deciding to not cut your lawn will not turn it into a species rich meadow. A lawn fulfils a completely different role in the garden than anything else and not cutting it simply turns it into an unkempt lawn – not a meadow. I have an ex-agricultural field which, after more than a decade of a meadow maintenance regime, is a species rich meadow. It has turned brown earlier this year than in a wetter summer but I shall leave it relatively late to cut it down because it’s still full of life : bats, dragonflies, swifts, swallows, martins, barn owls etc. all fly over it to hunt their chosen prey at different times of day—all part of life’s rich tapestry.