Introduction to Common Pests and Diseases:
1. Weakens the plants by sucking sap from them.
2. Eat different parts of plants.
3. Causes diseases to spread.
4. Affect the beauty of plants.
Names of Common Pests and Diseases
- Aphids 2. Brown rot 3. Cabbage root fly 4. Canker 5. Carrot flies
6. Mildew 7. Cucumber 8. Onion white rot 9. Whitefly 10. Root aphids
Aphids:
aphids (blackfly and greenfly) are common spring and summer pests. Blackfly stunt growth, eat flowers and distort pods. Pinch out the tops of broad beans once four trusses have formed. Greenfly is worse in a dry spring and hot humid weather as they carry viruses and cover plants in thick, sticky dew. Neither type of aphid can really be prevented, but spraying with a suitable insectside can help, try companion planting as a deterrent.
Birds:
Birds, mice and squirrels are attracted to seedlings and soft leaves when other food sources are scarce. Erect netting and pin down well to ensure there are no points of entry. Try birds scarers pushed in and around your pots.
Botrytis
Botrytis can affect all berries by covering them in a dense, grey mould, causing the fruit to rot in wet conditions. Fungicides are available.
Brown Rot
Brown rot is a fungus that affect many tree fruits, common in Summer and during storage. Discard all damaged fruit and remove dead shoots when pruning.
Cabbage Root
cabbage root fly manifests itself in a form of blue-tinged, wilting leaves on newly planted seedlings. Insecticides are available. Special discs can be placed at the base of seedling stems before transplanting. Fine netting can stop the flies laying their eggs.
Canker(1)
Canker (1) affect root vegetables, turning black and causing them to rot. Plants should be pulled up and destroyed. Chose a resistance variety.
Canker(2)
Canker (2) affect fruit trees by attacking the truck and branches of a tree, causing bark to shrink and expose the inner wood. The most serious form is bacterial canker which can affect Cherry and plum tree causing wood to ooze a gum-like substance. Chemical treatments are available, but seek expert advice.
Carrot Flies:
carrot flies Lay their eggs on foliage, and the resulting maggots burrow into the flesh, causing the roots to rot. Affected roots should be destroyed. Worse in a dry conditions.
Caterpillars:
Caterpillars eat holes in leaves from April and October in hot weather. Sprays are available. Inspect the top and underside of leaves for eggs, and remove and crush any that are found. Cover crop with fine netting to prevent butterflies laying their eggs.
chlorosis
chlorosis manifests itself in the form of yellowy leaves on acid-loving plant caused by too high a pH level. Check compost acidity level before planting and use ericaceous compost to increase acidity. Water with a rainwater and avoid using fertilizers that contain lime.
club root
causes the roots of the cabbage family to swell. Destroy all plants affected with club root. Improve the drainage of the compot and lime if necessary to help minimise the risk of encouraging the disease. Opt to grow resistance varieties.
coding moths
are caterpillars that feed on flesh around cores of orchard fruit in midsummer. Traps can be used to catch moths before they lay their eggs. Chemical sprays are available.
Flea beetle
is a very common problem showing as holes on The leaves of any green vegetable and leaf top, but doesn’t affect eating quality. Insecticides are available if you want to use them.
Mildew
comes in two forms: Downy: yellow blotches on leaves with a brownish mould on the underside, powdery: white patches on leaves, pods and fruit of sheltered plants in dry weather. Chemical sprays are available for both. Otherwise, destroy affected plant.
cucumber
Mosaic virus is a common, serious disease spread by greenfly. Leaves become puckered and mottled with yellow and dark green patches; affected plants witer and die. Destroy the affected plants, then wash hands and tools to prevent transmission. Take anti-greenfly precautions to prevent an attack.
onion flies
lay their eggs on all alliums. As a maggots hatch, they turn bulbs and stems too mush. Attacks occur between May and August, especially if they leaves get bruised. Avoid thinning where possible and destroy infected plants.
onion White root
is a fungal disease affecting alliums. A white fungus forms as alliums grow and quickly causes rot. Destroy infected plants.
pea thrips
are tiny Black or yellow insects that cause silver patches on leaves and pods. Worse in dry, hot weather. Chemical sprays are available; otherwise destroy affected plants.
potato blight
is when the foliage of related plants turn yellow and brown, and being to curl, causing potatoes to root and turn to slime. Look for assistant varieties. Always plant tattoos in fresh comspost.
Raspberry beetles
are smell, pale brown beetles that feed on new leaves and flowers of raspberry and BlackBerry in late May. Spray with derris or chemical sprays.
Red spider mites
affect all fruit, indoors and out. Mites suck the sap from leaves, living white spots and turning them brown. They are especially prevalent in hot weather. Natural predators, such as ladybirds for example, usually act as a natural pest control, but chemical sprays are also available.
Root aphids
attack the root of green vegetable and cover them with white, powdery damage practicularly in dry weather. Destroy affected plants. Keep plants watered to reduce the risk of an attack and look out for resistance varieties.
Calendulas and nasturtiums act as natural pest ‘deflectors’ and look very pretty too
scale insects
are flattish discs on the underside of indoor plants leaves, and leave a sticky dew on leaves and stems. Plants eventually stop growing. Chemical sprays are available, which should be used on neighbouring plants too as a precaution.
silver leaf
is a fungal disease affecting many fruits but especially plums. Leaves turn silvery and the upper surface peels away. Infected branches show a brownish stain. To reduce the risk of silver leaf, never prune during the dormant season.
Slugs
and snails attack any fleshy leaf and root in wet, damp weather, usually at the night time, leaving a slimy trail. Use pellets or other slug traps.
violet
root rot causes possible yellowing of foliage, but often only the roots are affected and show as a mass of purplish threads when pulled. Destroy affected roots
Wasps
are difficult to keep away, but try to pick fruit before it over-ripens and remove any decaying fruit. Place ‘honey traps’ in another area to keep wasps away from fruit trees.
A whitefly
is fast breeding in hot, dry weather. It can affect any plant but loves brassicas and tomatoes, and feed on plant sap. Chemical or soap-based sprays are available, or try companion planting.