August is often one of the warmest months of the year making watering essential. Recycle grey water if at all possible. Keep containers well-watered, as they will all now have matured to their full extent and be flowering profusely I hope!
A regular weekly liquid feed with an organic seaweed fertiliser is ideal. If you attend vigilantly to watering, feeding and regular dead-heading, many of your containers will continue to flower profusely well into the next two or three months.
Don’t neglect watering, ensuring you thoroughly wet the container and keeping water off the flowers and foliage as much as possible.
Rhododendrons, Azaleas, Camellias and Magnolias will appreciate regular watering perhaps twice a week if continuous dry weather prevails. Use organic mulches too to conserve moisture. If you neglect these colourful plants at this time of year and if they are put under stress for water they will suffer later on and you will have an impact on the yield and profusion of flowers next spring. A good mulch of organic material, such as well composted bark mulch or composted pine needles, will both help to conserve moisture, as well as suppressing weeds and reducing the ph of the soil. Container-grown shrubs will appreciate weekly feeds of an organic seaweed based liquid feed.
Flower borders & box hedge
Dead head frequently, removing faded blooms. Keep tall late flowering border plants such as Chrysanthemums and Dahlias well-staked. Tie in securely with garden twine. Use natural predators to control slugs.
Box (Buxus) will benefit from regular liquid feeds of organic seaweed extract. It will build up resistance on the plants and improve the foliage colour.
The Fruit garden
Summer prune sideshoots on restricted trees such as espaliers and fans to three to four leaves to form fruiting spurs. Summer prune restricted apples and pears. If necessary, prune nectarines, apricots and peaches after they have fruited. If necessary, prune plums, gages and damsons immediately after harvest. Water blueberries with rainwater if at all possible. Net blueberries against theft by birds. Remove straw and old leaves after strawberries have finished fruiting. Loosely tie together new blackberries and hybrid berry canes. Prune out fruited summer raspberry canes and tie in new canes.
The Vegetable garden
Keep tomatoes watered on a regular basis. Remember they will now consume considerable amounts of water, as the fruits develop. Pay particular attention to tomatoes and other vegetables growing in grow-bags, as they quickly dry out and may in fact require watering twice daily. Watch tomatoes for blossom end rot and other ripening problems. Tomatoes should be fed at least twice weekly now with an organic seaweed based liquid fertiliser. Watch for carrot fly and net crop with a fine mesh netting. Earth up celery.
Marrows, Squashes, Pumpkins: Using a slate or slab, raise the fruits slightly off the ground to keep them clean. This will help to have cleaner fruit, which will be more blemish-free when it comes to maturity and will also store and keep better.
Keeping the weeds under control: Using a sharp Dutch hoe, hoe weeds between rows of vegetables early in the day, allowing to wilt in the mid-day sun.
Cabbages and other brassicas (cabbage family) can be extensively damaged by caterpillar damage throughout the summer. In severe infestations the caterpillars can reduce the plants to mere skeletal wrecks. The offenders are the Large cabbage white, small cabbage white and cabbage moth. Plants affected include all members of the brassica family, including cabbage, brocoli, kale, Brussels sprouts, cauliflower. Some ornamental plants such as Nasturtiums and Geraniums may also be attacked. Main signs of damage include unsightly holes in the leaves and the presence of caterpillars. Caterpillars are generally active in the May to October period, usually more trouble is encountered in late summer/early autumn. Caterpillars are the larval stage of various butterflies and moths.
There are several species of caterpillars that feed on cabbages, other brassicas and other plants including turnip, swede, horseradish and nasturtiums. Large cabbage white butterfly caterpillars are yellow and black with obvious hairs on their bodies.
Those of small cabbage white butterfly are pale green and covered in short, velvet-like hairs. Cabbage moth caterpillars are yellowish green or brownish green with no obvious hairs on their bodies.
Symptoms: Holes are eaten in the leaves of all brassicas and damage may also be seen on the inner leaves of cabbages when the heart is cut through. Caterpillars and their excrement are often found on the plants
Caterpillars of cabbage moth and small white butterfly are more damaging, as they bore into the hearts of cabbages, whereas the yellow and black caterpillars of the large cabbage white stay mostly on the outer leaves.
Control: Inspect plants regularly and pick off the yellow butterfly eggs and caterpillars, as soon as observed. Growing brassicas under fine netting or horticultural fleece can exclude adult butterflies and moths from laying eggs on the crop. Care must be taken to ensure the netting doesn’t touch the crop or the adults can lay eggs through it. A biological control is available for caterpillars – this is supplied as a mixture of pathogenic nematodes usually sold as Fruit and Vegetable Protection.
Follow instructions carefully with these nematodes or beneficial parasites, as these are live creatures. They can’t be left hang around for too long and must be stored at the correct temperature until used (usually in a fridge). The longer the treated caterpillars and foliage stay wet, the greater chance of the treatment being effective, so apply during cool or damp weather.
Life Cycles: The adult butterflies lay eggs on brassica leaves. Large white butterflies lay clusters of yellow, skittle-shaped eggs on the top or bottom surface of leaves. Small white butterflies lay eggs singly on the underside of leaves. Cabbage moth lays spherical eggs in clusters on either surface of leaves.
The butterflies have two generations during the summer, cabbage moth has two or three overlapping generations.
Large and small white caterpillars are likely to be seen in June-July and August-September: cabbage moth caterpillars are active in July-September.
When fully fed, the caterpillars leave the plants to pupate. Cabbage moth pupates and overwinters in the soil and cabbage white butterfly larvae pupate on suitable vertical surfaces above ground level.