SUMMER is well and truly over in the garden, but colour still clings to the borders with a riot of late colour from plants such as Michaelmas daisies, dahlias and sedum. While more tender specimens begin to fade from containers and hanging baskets, these late-season stalwarts just go on and on, regularly producing new buds to replace spent flowers.

Most continue until the first frosts stop them in their tracks, and revel in the warm weeks we seem to get in late summer and early autumn.

Many of the late perennials were slow to come into flower this year, a contrast to their early performance last summer when many of the dahlias were in bloom by August.

By this time, Aster frikartii ‘Monch’ had been covered in its large lavender blue daisies for weeks. This year ‘Monch’ started flowering in August, which was disappointing in July but great now as we can enjoy the still fresh sight of the wonderful blooms.

This really is a great Michaelmas daisy to have and I would choose it above all others if I could only have one in the garden.

With ‘Monch’ grows a pink dahlia, its name lost in time. This old tuber has survived a number of years in the garden without being lifted for winter.

I did wonder if I had been mistaken in carrying on this lazy tradition when we had that cold snap last February. Some dahlias didn’t appear this summer and the few that did have been, like ‘Monch’, weeks later than usual.

However, three are now well into flower and have formed good, strong bushy clumps of stems and foliage topped with numerous buds. The recent removal of a large tree next door has flooded the garden with light, which should also help the flowers open before cooler weather arrives.

New dahlias bought to replace those that were lost have also been disappointing and none are in flower, but it isn’t their fault. The tubers were planted in April and began to grow immediately, pushing lovely new shoots strongly through the compost.

After careful hardening off, they spent their first night outside only to be completely eaten by snails, which set them back by weeks.

One, a dark-leafed variety called ‘After Eight’ has at last formed a few tight black buds and it is now a race to see if they can open before it gets too cold. I’m sure Gardeners’ World had an amazing display of these dahlias in July or early August. Note to self, must do better next summer.

The tiny pink flower that can be seen in the photograph growing with ‘Monch’ and the pink dahlia is a new hardy geranium tried in the garden this year.

Geranium ‘Bob’s Blunder’ has done really well, spilling on to the path and sending the odd stem up into its taller neighbours. It needs more space than it has been given, but nevertheless has managed to grow well in its overcrowded designated spot.

There is to be a sort-out in the bed this autumn and ‘Bob’ will be given a better spot where we can better enjoy the subtleties of the small chocolate foliage and tiny blooms.

Weekend catch-up

WALLFLOWERS can be had from garden centres and market stalls now. These biennials are often sold as bare-rooted clumps at this time of year, the often wilted bundles wrapped in newspaper to be carried home for immediate planting. Don’t be put off if they look a little droopy, for an hour or so plunged in a bucket of lukewarm water will soon perk them up. Once soaked, divide the clump into individual sections and plant in a sunny spot. Water well then leave.

They will soon form bushy little plants that remain evergreen and flower in spring. Some will be scented and are perfect for a bed by the back door or under a window where the perfume can wander into the house on a warm April day.

Gardening TV and radio

Tomorrow.

8am, BBC Radio Humberside, The Great Outdoors. With Blair Jacobs and Doug Stewart.

9am, BBC Radio Leeds, Gardening. With Tim Crowther and Joe Maiden.

2pm, BBC Radio 4, Gardeners’ Question Time. Matthew Biggs, John Cushnie, Bunny Guinness and chairman Peter Gibbs help gardeners from New Waltham near Grimsby. Jeffrey Bates from the RHS gives tips on how a village or town can enter 2010 Britain In Bloom and the gardening weather forecast is at 2.40pm.

Friday.

3pm, BBC Radio 4, Gardeners’ Question Time. Matthew Biggs, John Cushnie, Pippa Greenwood and chairman Eric Robson visit the John Innes Conservation Centre. Matthew Biggs is invited to the Queen’s allotment to review its progress as part of the RHS Grow Your Own Campaign and the gardening weather forecast is at 3.40pm.

8.30pm, BBC2, Gardeners’ World. Toby Buckland plants a hazelnut tree in the vegetable garden and Alys Fowler searches out winter bedding plants in nurseries and garden centres.