Traditionally the month for holidays and merrymaking, August is, in fact, one of the quieter months in the gardener’s year; the production of new growth has slowed down, and the process of ripening and maturing is evident. One can relax a little and the ornamental garden can be left to itself to a large extent, merely removing deadheads, replacing supports, and spraying for m1-dew. This is a fungus disease, characterized by a white powdery coating on leaves, stems and buds, and at this time can be a great nuisance on ornamentals, particularly if the soil is dry or the garden rather stuffy. Dinocap or sulphur dust, or in solution, will restrain its increase. Watch for it also on apples, roses and hedge plants.
Mowing the lawn and irrigating it continue in hot weather. Hedge cutting can continue, or start, if missed last month. Shrubs which flower this month, as well as those which started in July, are hibiscus, more hebes, ceanothus, caryopteris, ceratostigma, buddleias, species clematis and more hydrangeas.
In late August Scotland comes to town, in that the heaths and heather bust into a purple glory and continue so for several months. It is not strictly accurate to confine the colour to purple as the modern hybrids and cultivars come in all shades of purple as well as pink, rose, and white, with foliage in grey, green, yellow, cream- or yellow-variegated, and red- or pink-tipped. Given an acid soil, preferably inclined to be peaty, but not fertile, heathers, once planted, will continue to be a carefree joy. Clipping the tops with shears when they have flowered, or in spring for those that bloom in late summer and autumn, is virtually all that need be done. For extra plants, pull down outside shoots to ground level and cover their stems with soil. Eventually, roots will form and new plants (layers) can be detached.
A border of heathers really is a patchwork of colour, and with the dwarf conifers in their equally varied foliage colours and silhouettes interspersed among them at suitable intervals, such a planting can only increase in beauty and effectiveness through the years. A heather collection could be started with the cultivars of Calluna vulgaris, which are in flower from August to October and later, such as ‘Be°ley Gold’, acid yellow leaves and white flowers; `Cuprea’, copper-bronze leaves and purple flowers; rose-pink ‘H. E. Beale’, and purple ‘Mrs Pat’ – ‘Silver Queen’, lavender flowers and grey-white green leaves, and pink-lilac ‘County Wicklow’.
Propagation of various plants by various methods can continue; semi-ripe cuttings can be taken, and at the end of the month pelargonium cuttings can be started, also conifer heel cuttings, 2 in. long, placed in a cold shady frame in pure sand or a sandy compost. It is still possible to root soft cuttings, and layering may be started at the end of August. Disbudding of chrysanthemums continues, and the top bud of the outdoor ones can be. Secured this month. Biennials to bloom next year can be planted out.
Freesia corms for December flowering can be planted early in the month, about 2 M. deep, in pots put out of doors in a shady place. So can prepared hyacinths for Christmas, but after potting they should be put in a cool dark place for three months. Iris reticulata for January flowering, and winter flowering begonias, can be potted – Christmas -cactus and cyclamen can be started this month, if this has not already been done. Cyclamen will have spent the last two or three months out of doors in a shady place, and can now be moved to a lighter one, watering thoroughly to start them into growth. If new compost is required, they should be repotted before watering, using a slightly acid compost, and removing all the old. The corm is replaced so that it is only half buried.
Watering and damping down of pot plants should continue, and routine tidying of fallen leaves, flowers and dying vegetation generally.
Out of doors runner beans and self-blanching celery will be ready. Vegetable seeds which can still be sown outside include spring cabbage, lettuce, radish, spinach beet, winter spinach and endive; young plants of broccoli, winter cabbage and savoys can all be put in.
Herbs are still good for picking and drying, on a warm day when the foliage is dry. Second early potatoes will be ready, and onions can be lifted and spread out in the sun in single layers in boxes to dry before storing. Vegetables and salads in season this month are runner beans, cabbage, carrots, lettuce, onion, peas, potatoes, spinach, spinach beet, marrows (including courgettes), beetroot and garlic. Crops which have finished should be cleared out and the ground manured or not, depending on the rotation. Where broccoli, spring cabbage, savoy, onion and early summer lettuce are grown, manure helps.
August is the best time to clean up the soft fruit, removing the protective netting where this is temporary, as soon as the crop has been gathered. Strawberries can be burnt over if straw was used to keep the fruit clean, otherwise the top growth can be mown off and raked away, together with runners that are not wanted, old leaf and fruit debris, and the soil lightly hoed, fed and watered, and re-strawed. This will result in strong new growth, and probably a second crop of flowers which can be cloched for autumn fruiting; the variety ‘Talisman’ is very prone to flower a second time.
Old fruited canes of raspberries should be cut down to soil level and removed, also poor new cane growth. The remaining new canes are tied in, and thinned if still too plentiful. Blackcurrants are pruned so as to remove most of the old fruited branches, either to the ground or to a well-placed good new shoot. Branches close to the ground should be removed, strong or not, as they only get pulled down by the weight of fruit and trampled underfoot by pickers.
Gooseberries and redcurrants can be summer pruned, that is cut back to just above the fifth leaf from the base, not counting the basal cluster of leaves, of the new growth that season. The new leading growths are allowed to remain until winter. Clean up all weeds, leave the straw mulch until autumn, and renew where the soil is showing through.
Apples and pears trained as cordons and espaliers or other formal shapes can also be summer pruned in early August, finishing the job in winter. Remove the new sideshoots back io just above the fifth good leaf, excluding the basal cluster, when the shoot has started to become firm and brown at the base, but is still green at the tip; leaders are left uncut. If pruning is done too early, it will result in secondary growth, which will use up the tree’s energy unnecessarily, and will be cut back by frost, so providing an entry for disease.
Some branches may be breaking or about to break under the increasing weight of ripening fruit, and branch propping may be a necessary job. Woolly aphis (American blight) may be apparent on apple trees, so spray with malathion under strong pressure, or scrub the patches with a wire brush dipped in methylated spirits if there is not too much of the pest and the trees are small.
This is the month of the plum and varieties in season include ‘Victoria’, !Czar’, ‘Early Rivers’, ‘Denniston’s Superb Gage’, ‘Oullin’s Golden Gage’, ‘Cambridge Gage’, ‘Black Prince’, and ‘Bountiful’. The acid or Morello cherry will also be ripe in early August.