Strimmers at the ready – recent heat and rain means hedges and borders have started to look unruly
If you’ve been away or just enjoying your garden, there are plenty of gardening chores to be done. Sunshine, very warm temperatures and torrential rain has resulted in a lot of growth and hedges, in particular, will be looking quite hairy.
So it’s time to trim those evergreen bushes such as box and privet as well as conifers. Don’t trim conifers back into old wood unless it’s yew, as they won’t put on fresh growth. Wisteria is looking a bit mad as well — you need to cut back all that whippy growth to about 5 or 6 leaves in length.
Herbaceous borders can look a bit messy and tired now. Some plants such as dahlias may need a bit of staking to prop them up while other perennials are finished and need to be cut back to ground level. This is a personal choice in many cases — judge yourself whether the plant will decay well and should be left for winter interest — but if it’s sludgy and brown, you’re better off getting rid of it. There are tonnes of flowering plants available at the moment such as crocosmia, asters, and rudbeckias so you can fill in any bare gaps with some lovely late summer flowering plants.
Pots and containers still need plenty of care so maintain feeds and watering. If you have camellias or rhodos in pots, it’s very important that they don’t dry out now while they are forming next year’s buds. Remove any tired bedding and put on the compost heap if you have one. Remember to give the compost heap a turn every month to help aerate.
I’ve been dead heading roses and hoping to encourage that magic second flush of flowers. Rambling and climbing roses can be pruned now unless they are repeat-flowerers. Remove suckers from roses bushes and from the base of trees. If you have variegated plants, remove any stems that have reverted to being green.
It’s harvest time for loads of crops so catch fruit and veg at its best, either for eating now or storing for the winter. Onions are ready when the foliage starts drooping over. You can tell if sweetcorn is ripe by squeezing a kernel and milky juices come out.
Look after pond life — keep water levels topped up, remove blanket weed and cut back yellow foliage on pond plants.
How’s the lawn? Depending on where you live, it might be parched yellow, in which case leave it alone until rain restores its green lustre. If you’re lawn obsessed and won’t be happy unless you have a perfect green swathe it’s a good time of year to tackle perennial weeds in the lawn — preferably by digging them out.
Don’t feed it any more nitrogen at this stage — later in September and October you can apply an autumn fertiliser which is high is phosphates and potash to encourage strong root development ahead of winter.
Collect seed from plants you’d like to propagate… or eat! I’ve been eyeing up a wild fennel in my garden (a fantastic architectural plant) and will collect the seeds shortly for culinary use. The same goes for poppy seeds — you can use these in baking — or scatter them for next year.
To ensure some winter greens, spring cabbage, turnips and quick-growing crops such as salads and radishes can all be sown now.
Dry weather is great for getting any paint jobs done such as sheds, fences or furniture that need a face lift. Is it time to try out a new colour scheme?
Finally, we will soon be in bulb-planting season so, once you have weeded and cleared the borders, it’s time to get purchasing bulbs and get ready to plant them next month. In the meantime, colchicum, sternbergia and autumn crocus can be planted in the ground as soon as they are available to buy in the garden centre.
Salvia season is in full swing. Deservedly popular, salvias provide masses of colour and are often one of the last perennials to keep flowering at the end of summer. ‘Wendy’s Wish’ is a gorgeous new variety with deep magenta, long tubular, citrus scented flowers borne on red stems.
What’s the best way to tell if the buds on my dahlias are spent and is deadheading them really necessary?
Maria, via Instagram
That’s a great question — actually, it’s quite easy to tell. The new flower buds are round in shape, while the spent ones become pointy in shape.
Deadheading is not necessary but it stops the plant putting energy into developing seed, leaving it with more energy to produce more flowers — so it’s well worth it as dahlias have the ability to keep flowering until first frosts.
Submit your gardening questions to Diarmuid via his Instagram @diarmuidgavin using the hashtag #weekendgarden