There’s nothing more annoying than to find that plants you have nurtured are being attacked. Whether by or insects or diseases that cover the leaves and stems of the plant, pests and diseases are highly detrimental and should be remedied as soon as possible. Identifying them on your plant can be difficult though, and people often don’t notice until the plant is showing definite signs of stress, so here’s a guide to identifying, treating and preventing the most common pests and diseases.
Protecting vegetable/fruit plants. Always check on the label of any pesticide that you can use the product on your crop, also note the of times you can apply it, and the interval needed between treatment and harvest. If you cannot find a suitable product, cover with netting or insect protection mesh as appropriate to act as a barrier.
Aphids. The most well known of these are Greenfly & Blackfly, they gather around the succulent young stems, leaves and buds of many plants, extracting the sap. Aphids can quite easily be seen, signs to look for are curled or contorted young leaves, and/or a black mould on the leaves that feed off the honeydew that the aphids produce aphids attack woody stems further down the plant – they look like a layer of mould. Treat with a systemic insecticide, which works inside the plant and kills the aphids through the sap they consume. If you’ve had problems before, keep a close eye on the young growth of roses, fruit trees and other susceptible plants in early summer.
Caterpillars. These are the pupae of moths and butterflies, most of which do not become a serious pest. They eat holes in the leaves of annuals, herbaceous perennials, brassicas and some shrubs. Spray leaves with a systemic insecticide where appropriate, or pick off and destroy if this is manageable. Caterpillars can be voracious feeders , and a bad infestation can strip plants before they are noticed. Monitor plants that have been attacked in previous years.
Slugs & Snails. Possibly the gardener’s worst enemy, slugs and snails lay waste to perennials such as Hostas, Delphiniums and Irises, as well as stripping down bedding and vegetable plants, leaving nothing but the tell-tale slime trails. Worst in damp weather which makes it easy for them to get around. Sparingly scatter slug pellets around affected or susceptible plants.
Vine Weevil. Grubs of vine weevil mostly attack perennials and alpines in containers. The adult beetles eat U-shaped notches in the foliage in summer and leave their eggs, which hatch and eat the roots, leaving the foliage above loose and shrivelled on top. Where plants have been attacked, bag up and dispose of the compost in the dustbin and wash the pots out thoroughly. Treat nearby containers with a water-in Vine Weevil Killer, this can also be done should notches be seen in the leaves in summer.
Powdery Mildew. A common disease of roses, honeysuckle, apples, Asters and many other plants. White powdery mould forms on the surface of the leaf, hampering photosynthesis. Spray with a suitable fungicide.
Black Spot. A Rose plant disease that causes large black blotches to appear on leaves from July, eventually causing them to go yellow. Use a rose spray, and in advance of symptoms emerging if possible. Clear up fallen rose leaves, as the disease can overwinter.
Rust. that affects Hollyhocks, Roses, Antirrhinums, Pelargoniums and other shrubs and flowers. Raise pustules, usually orange or brown, on the underside of the leaf. Occurs when plants are overcrowded. Spray with fungicide or pick off the affected leaves.
That’s just a sample of the most widespread pests and diseases, if you need help with any plant health problems, just visit your local Cherry Lane Garden Centre, preferably with a piece of the affected plant.
