This month, like March, is a pivotal month for refocusing, this time on winter. The more effort extended now should equal less work later. The idea of autumn planting is to beat the major winter rains so that roots establish over winter while benefiting from soil still warm.
Now is also the time to clear out all the old summer annuals and vegetables, tidy up perennials, and to prune, transplant, divide and mulch.
Trees and shrubs
October is the optimum time to put in those plants which form the backbone of your landscape and give pleasure over years, including trees. Most shrubs for hedges and screens can be also planted now as can vine-like plants, such as Tecomaria capensis, jasmine and ivy.
Choose plants which appreciate your particular climate zone and when planning and planting, group together those with identical watering needs.
Wait for spring or early summer to plant tropical species, but if you do take the chance to plant now, remember to protect them from frost and don’t fertilise until the warm weather.
Deciduous fruit trees
Don’t fertilise and from the middle of the month water less but don’t let them dry out completely. These trees need their winter dormancy.
Plants several years old which grow in clumps can be divided now, either bulblike ones or perennials. Some plants when crowded bloom at their best, while others stop flowering altogether, so get to know how each plant reacts. Amongst those to divide now are iris, daylily, gazanias, ivy geraniums, some daisies and small birds of paradise (larger ones have immense clumps which only a chain saw can separate!).
Dig up gladioli corms and dry on newspaper for a week or two in shade. Then separate the new and old corms, discard the stem, roots and old wider, flatter corm on the bottom. The smaller, flatter corms that have grown on top can be kept for February planting. Store cool and dry and for best results roll the new corms in a proprietary dust. The cormels, tiny new corms, could be planted but are often difficult to sprout.
Progressively prune zoned geraniums by cutting out two of the longest branches, or several more if you have not been doing this regularly. Cut straight across a branch about one centimetre above a joint with two healthy leaves remaining, as bare stubs do not re-cover. For those in pots, remove some old soil on top and replace with new. Feed only occasionally during the winter but continue to prune leggy stems year-round.
Treat ivy geraniums similarly by cutting back the longest branches and refreshing the soil in pots. Those in the ground can be cut back lightly and both potted and grounded ones may be fed and watered.
Hardy water lilies (which appear to float on the water rather than stand high above it) should be divided and potted every three years. Remove the containers from the water and inspect the roots – if they fill the container then it is time to re-pot. Remove dead leaves and any baby plants which can be potted up in separate containers. Then remove some of the old soil from the roots and place in a larger container, filling it with a prepared soil or a rich garden loam with no manure, peat, bone meal, perlite or wood shavings. To further prevent the water from getting muddy, cover the surface with one or two centimetres of washed sand or pebbles or wire netting.
Hardy lilies which have yellow leaves but don’t look crowded may just need fertiliser. Push a slow-release tablet specific to aquatic plants down below the soil surface. Top with protective sand, gravel or wire netting.
There is still time to purchase bulbs, but don’t tarry as they have been available since September and you will want the best you can find. Buy anemones, daffodils, grape hyacinths, Dutch irises and ranunculus now, but wait until November to plant as the soil is still too warm. Keep them cool and dry, but not refrigerated.
In the meantime, you can still plant South African bulbs, such as croscosmia, freesia, ixia, watsonia, and narcissus as well as lilies which should be planted as soon as you get them home.
Hyacinth, tulip and crocus bulbs can be put in the refrigerator crisper basket for six to eight weeks before planting. Store in paper not plastic bags and do not allow to freeze. Do not store with fresh fruits (e.g. apples, bananas, pineapples) which emit ethylene gas which will impact on the bulbs.
Water with two centimetres twice a week and feed now for the last time this year.
Annuals and perennials
Continue to switch flowerbeds and containers from summer to winter annuals and those perennials you wish as October is the best month to finish this job. Flowers to put in from transplants now include calendula, cineraria, cyclamen, dianthus, foxglove, Iceland poppy, nemesia, pansy, primrose, snapdragon, stock, and violas. Plant and feed as soon as possible for fast bloom. With luck, they may flower before Christmas and continue flowering over winter; if not, growth and bloom will only be with the warmer spring weather.
Even this late in the year you can plant from seed. Try California poppy, clarkia, forget-me-not, hollyhock, lavatera, nasturtium, snapdragon and many wildflowers.
Cool-season lawns will be starting to speed up while warm-season ones will be slowing down. Reset mower blades to cut cool-season grasses shorter now, to three centimetres. Feed with a complete lawn fertiliser for root and top growth. Now is the time to address problems such as fungus or the need to de-thatch or weed. October is the best time to plant cool-season grass from seed.
Cut warm-season lawns at the same height you cut in the summer and continue feeding through the month.
Clear out the remnants of the summer vegetables. A good clean up now will help limit bugs and disease. Dig the soil, aerate, and break up clods then, with a fork, mix in manure or compost. This is the ideal time to use organic additions to improve sandy soil to achieve more water retention or clay soil to improve drainage.
Try growing by seed broccoli, beets, cabbage, cauliflower, fava beans, lettuce, radishes, spinach, although generally broccoli, Brussels sprouts, cabbage, and cauliflower do better from transplants. You can also try cilantro and rocket from seeds as these like cooler weather.