Thereís nothing like the first sharp frosts for putting an end to autumn. Suddenly, the leaves start falling like snow and the dahlias go from green and healthy to black and soggy overnight. Nature has a way of reminding us to get the autumn tasks done before itís too late, but also to appreciate the beauty of what is still around us.
You canít stop the leaves from falling, but you can collect them up and make superb leaf mould to enrich the garden soil next summer. This is a great job for young gardeners! Simply gather the leaves into an old compost bag turned inside out so the black colour absorbs heat from the sun. Water them lightly to begin the rotting process - and you can add a compost activator at this stage to speed things up if you wish - then fold the top of the bag over and leave in a sunny spot out of the way until next year. By mid summer, most types of leaves will have rotted into rich, crumbly material that you can spread over the soil as a mulch and let the worms incorporate it into the soil for you naturally. The exception are oak leaves and some evergreens, which rot down more slowly.
Once the dahlias have been frosted, itís time to pack the tubers away safely for the winter. Give the stems a few days to die back, then trim them off at about 15cm (6Ē) high and dig the plants up. If the stems look wet, lay the plants upside down to drain for a few days. Then label the plants and pack them into a tray or cardboard box, surrounded by straw or shredded newspaper for insulation and leave them in a dark, cool, but frost-free, spot until the New Year. If you have somewhere with frost protection, like a greenhouse, you can repot them in late winter and start them back into growth so you get some early cuttings.
You can take cuttings of scented-leaf, zonal and ivy-leaved pelargoniums as you cut them back for the winter. Stand the mother plants in a sheltered, preferably frost-free spot and be prepared to fleece them if the weather turns really cold. The cuttings will need to be kept in a cool room or frost-free conservatory, or in a greenhouse where you keep the heat on stand-by.
Your summer and autumn containers may need attention after a frost unless you have chosen hardy winter plants like pansies, polyanthus, cyclamen, ivy or heathers. Clear away damaged flowers and leaves whenever you see them, to reduce the chance of grey mould as the weather gets damp, but make sure the containers have enough water. Keep them slightly moist, never wet, and stop using containers with a base reservoir - these are ideal in summer, but can hold far too much water in wet weather.
Berries and fruit
Cold weather and shorter days trigger a reaction within woody plants that makes the sugar levels rise, so the berries mature and the colour develops. The birds will certainly tell you when this happens, because they will suddenly begin eating everything.
Pyracantha is fascinating for this, because the different varieties mature at different times each year and where one year, the birds will attack the yellow ones first, another year itís the reds or oranges. The best way to observe this is in a mixed hedge - much appreciated by blackbirds, thrushes, jays, bull finches and even wood pigeons in our garden.
The other effect of cold weather and the short days is that it means a good display of flowers and blossom next spring and summer - and usually a good harvest too, so thatís something to look forward to next year!
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