Autumn’s here! 5 top tips for October gardening
That telltale chill is in the air, so it's time to knuckle down and prep your patch for the changing seasons.
October marks the end of the growing season in the UK. Most plants will be starting to show their autumn colours and either preparing to go to sleep for the winter, ready to reappear next spring (in the case of perennials) or giving a final finale before the frosts kill them off (in the case of annuals).
There’s plenty that can be done to prepare for the change of seasons and ensure that your garden returns with even greater splendour next year.
Tidy up – selectively!
There can be a temptation, as things start to die back and turn brown, to chop everything! However, try to hold back, as the skeletons and seedheads of some plants glistening with frost can be an important part of bringing interest to the winter garden. Seedheads also provide food for birds over the winter months. Plants such as Eringiums (sea holly), with their spiky architectural form and Lunaria annua (honesty), with their large translucent papery seedheads are so architectural that it is worth growing them just for their contribution to the autumn/winter garden. Ornamental grasses such as Miscanthus with its slender, fluffy flower spikes stand all winter, and are definitely worth sparing the chop!
Some dead growth is worth removing, especially if showing signs of decay or fungal growth. By now, some leaves may have a white powdery coating (mildew), and it’s best to cut this all back with secateurs and put in your green bin rather than compost heap. While you’re at it, take the opportunity to remove weeds, digging out those with thick or fleshy roots.
Protect tender perennials
Dahlias will go on flowering right up until the first frost if you continue to deadhead them. The tubers go on growing up until this point, but as soon as the first frost appears the leaves will shrivel and turn black. At this point, lift the tuber with a fork, shake off the soil and then place in a very slightly moist, but not wet, mix of grit and compost. Leave in a cool but frost free place, checking that they have not dried out completely, until spring, when they can be re-potted ready for planting in early summer. Alternatively if you live in a protected spot, it may be possible to overwinter them in the ground. After the first frost, remove the leaves/stems and cover them with 5-10cm of mulch to protect them.
If you have any tropical plants such as Bananas or Canna Lilies or Citrus trees, as well as tender plants such as Echiums or some Salvias, they will benefit from being kept in a cool, frost-free conservatory. Most plants will do much better in a cool (5-10 C) light environment than a centrally-heated house, so don’t be tempted to bring them indoors.
Collect seeds from your favourite plants
Although growing plants from commercial seed is relatively cheap, you can get new plants absolutely free by collecting and growing from your own seed and some are so easy to collect (like Nicotiana) that it can be fun to do. It probably makes the most sense to do this with annuals (such as Californian poppy) and biennials (such as Foxglove) that you will need to grow each year to have them within your garden. Some plants (like Amaranthus or ‘Love lies bleeding’) may already have seedlings popping up, but they may not make it through the winter, so it’s best to collect seed and replant in the spring as an insurance policy!
Prune climbing roses
Climbing roses are those that repeat flower all summer and into autumn, whereas a rambling rose, which often grows bigger, flowers once around June time. If you prune climbing roses now, it prevents them becoming a tangled mess and creates a more healthy, vigorous plant with more flowers next year. First remove dead, diseased or dying branches. Then tie in any new shoots to supporting wires, pillars or arches. Prune any side shoots that have flowered back by two thirds of their length. If the plant is heavily congested, cut out any really old branches from the base to promote new growth.
Give your hedges and lawns a final trim
Hedges that are trimmed now will maintain a crisp shape throughout winter and will look great when the sharp lines are lined with frost. Just give then a trim but don’t cut back into old wood leaving no leaves as they will not have time to regrow before the cold weather sets in. They should not need doing again until the spring. You can also give your lawns their last cut – increasing the height of the cut so that they look tidy, but not scalped and open to moss moving in and choking the grass.