Garden Pests & Diseases: Prevention & Control

Great battles are fought every day as gardeners strive to protect their precious crops, while a multitude of garden pests and diseases seek to destroy them!

Pest and disease control presents a huge challenge for the gardener, and identifying the cause of the damage is often the hardest part! Those sneaky garden beasties don't always show themselves, so how do you know whether your plants were eaten by a slug or a squirrel? And just what is the difference between downy mildew and powdery mildew?

As our Facebook and Twitter followers have asked us so many questions, we decided to bring all of the answers together to share this information and hopefully solve some of your garden problems too!


If you can't find a specific answer to your problem then here are eight general tips to help reduce the risk of attack.

  1. Avoid using too much high nitrogen fertiliser as this promotes lots of soft leafy growth which is particularly appetising to garden pests.
  2. Erect physical barriers - covering crops with fleece or planting fruit in a fruit cage will often prevent pests from reaching your crops.
  3. Know your enemy - Many pests and diseases are specific to particular crops. Find out what is likely to attack your crops and the type of damage that it will cause. Once you know what you are looking for it is much easier to identify a problem when it occurs.
  4. Keep your eyes peeled for the earliest signs of attack and take action. Don't let the problem get out of hand.
  5. Practise good garden hygiene. Keeping your garden, your greenhouse and tools clean and well maintained can prevent many diseases.
  6. Improve your cultivation practises. Plants can become stressed by poor watering regimes, lack of nutrients, inadequate light and ventilation, or poor soil conditions. These stresses make them more susceptible to damage attack by pests and diseases.
  7. Encourage natural predators to the garden. Ladybirds and lacewings will happily munch their way through aphid colonies, preventing their spread throughout your garden.
  8. If you need to resort to using chemicals then make sure that you read the label carefully, and follow the manufacturer's instructions to the letter. Never spray chemicals near ponds and other water habitats. Always choose a still, calm day to undertake spraying. Always wear appropriate safety equipment.


Pests and Diseases - Common Questions

As our Facebook and Twitter followers have asked us so many questions, we decided to bring all of the answers together to share this information and hopefully solve some of your garden problems too!





• What are ants?
• How to recognise ant damage
• Which plants do ants eat?
• How can I control ants?
• How can I get rid of ants destroying my acers in my garden?
• How can I stop ants on my garden vegetables?
• How do you get rid of ants in compost bins?
• Why are there lots of ants on my peonies?
• Why have I got ants all over the trunks of my apple trees? Will this be a problem for the fruit?


• What are aphids?
• How to recognise aphid damage
• What plants do aphids eat?
• How can I control aphids?
• How do I get rid of aphids on my apple tree?
• How do I control blackfly on my globe artichokes?

Bay Tree Suckers

• Why are my bay tree leaves yellow and curled?
• What are bay tree suckers?
• How to recognise bay tree sucker damage
• What plants do bay tree suckers eat?
• How can I control bay tree sucker damage?

Bean Seed Fly

• What are bean seed flies?
• How to recognise bean seed fly damage
• What plants do bean seed fly eat?
• How can I control bean seed fly?


• Which birds are garden pests?
• How to recognise bird damage
• How can I control bird damage?


• Why are cats a gardener’s problem?
• How do I recognise cat damage in my garden?
• Which plants do cats eat?
• How can I protect my plants & garden from cats?

Cherry Aphid (Cherry Blackfly)

• What are cherry blackfly?
• How to recognise cherry blackfly damage
• What plants do cherry blackfly eat?
• How can I control cherry blackfly?

Euonymus Scale

• What is euonymus scale?.
• How to recognise euonymus scale damage
• What do euonymus scale eat?
• How can I control euonymus scale?
• Why has my Euonymus hedge suddenly died?

Gall mites

• What are gall mites?
• How to recognise gall mite damage
• What do gall mites eat?
• How can I control gall mites?
• What are the grey fluffy growths on my mock orange? I cut a small piece, and it's bright green inside.


• What are leatherjackets?
• How can I recognise leatherjacket damage?
• What do leatherjackets eat?
• What's the best way to control leatherjackets?

Pear Leaf Blister Mite

• What are pear tree blister mites?
• How do recognise pear tree blister mite damage?
• What do pear tree blister mites eat?
• How do I control pear tree blister mites?

Plum Fruit Moth

• What are plum fruit moths?
• How do I know if I have plum fruit moths?
• How can I control the spread of plum fruit moths?


• Why are rabbits a problem for gardeners?
• How do I identify rabbit damage?
• Which plants do rabbits eat?
• How do I protect my plants & garden from rabbits?

Scale Insects

• What are scale insects?
• How do I tell if I have a scale insect infestation?
• What plants do scale insects threaten?
• How do control the spread of scale insects?


• What are slugs?
• How can I recognise slug damage?
• What do slugs eat?
• How can I control slugs?

Snails & Snail Eggs

• What are snails?
• How to recognise the presence of snails
• Which plants do snails eat?
• How can I control snails?
• Can I use nematodes to get rid of snails?
• Why have the stems of my clematis been stripped of their outer layers? Some of the stems are dead and there are holes in the leaves
• What are the small transparent jelly things on the back of my water lily leaves?

Spider Mite

• What are spider mites?
• How do I recognise spider mite damage?
• Which plants do spider mites eat?
• How do I control the spread of spider mites?


• Why are squirrels a problem in the garden?
• How do I recognise squirrel damage?
• What do squirrels eat?
• How can I protect my garden and my plants from squirrels?
• How can I stop squirrels attacking my flower pots?

Tawny Mining Bee

• What are tawny mining bees?.
• How do I tell if I have tawny mining bees in my garden?
• What plants do tawny mining bees eat?
• How should I respond to tawny mining bees in my garden?

Viburnum Beetle

• What are viburnum beetles?
• How do I recognise viburnum beetle damage?
• Why have the new leaves on my Viburnum Opulus plants turned into lace?
• What plants do viburnum beetles eat?
• How can I control viburnum beetles?

Vine Weevils

• What are vine weevils?
• How can I recognise vine weevil damage?
• What do vine weevils eat?
• How can I control vine weevils?
• Which plants do vine weevils not like?


• What do worms do?
• How to recognise worm activity
• What damage can worms do?
• How do I get rid of worms in my lawn?




Apple Scab

• What is apple scab?
• How to recognise apple scab
• How do you prevent apple scab?

Bacterial Canker

• What is bacterial canker?
• How do I tell if my tree has canker?
• How to treat bacterial canker

Blossom Wilt

• What is blossom wilt
• How do I deal with blossom wilt?
• How to prevent blossom wilt


• What is botrytis?
• How do I recognise botrytis?
• How to treat botrytis
• How do I prevent botrytis?

Brown Rot

• What is brown rot?
• How to identify brown rot
• How to prevent brown rot

Clematis Wilt

• What is clematis wilt?
• If it's not clematis wilt, what is it?
• How can I treat clematis wilt?

Downy Mildew

• What is downy mildew?
• How do I recognise downy mildew?
• Is there any cure for downy mildew?
• Disease resistance

Fungal Disease

• What is a fungus?
• How to spot a plant fungal infection
• How to prevent plant fungal infections
• What to do if your plants are infected with fungi
• Why are my begonia stems rotting?
• What's the white powder on my potato leaves?
• Does your Japanese Maple bush leaves have tiny white speckles on?

Geranium Blackleg

• What is blackleg
• How do I recognise geranium blackleg?
• How do I prevent geranium blackleg?
• How to treat geranium blackleg

Honey Fungus

• What is honey fungus?
• How to recognise honey fungus
• How to treat honey fungus
• How to prevent honey fungus

Leaf Scorch

• What is leaf scorch?
• What to do about leaf scorch
• Are there diseases that cause leaf scorch?

Leaf Spot

• What is leaf spot?
• How to treat leaf spot
• How to prevent leaf spot

Leek Rust

• What is leek rust?
• How do I deal with rust on my leeks?
• How to prevent leek rust

Lily Disease

• What causes lily disease?
• How to treat lily disease
• How to prevent lily disease

Peach Leaf Curl

• What is peach leaf curl?
• How can I prevent peach leaf curl?
• How to treat peach leaf curl

Pear Rust

• What is pear rust?
• What to do about pear rust

Phytophthora root rot

• What is Phytophthora ramorum?
• What to do about phytophthora ramorum root rot

Potato and tomato blight

• What is potato and tomato blight?
• How to recognise potato and tomato bligh
• How to treat potato and tomato blight
• How to prevent potato and tomato blight

Powdery Mildew

• What is powdery mildew
• How do I recognise powdery mildew?
• How do I treat powdery mildew?
• How do I prevent powdery mildew?

Silver Leaf Fungus

• What is silver leaf fungus?
• How do I recognise silver leaf fungus?
• How to treat silver leaf fungus
• How to prevent silver leaf fungus

Tomato Greenback

• What is tomato greenback?
• How to prevent tomato greenback

Tomato Leaf Curl

• What is tomato leaf curl?
• What causes tomato leaf curl?

Tomato Stem Canker

• What is tomato stem canker?
• How to recognise tomato stem canker?
• How to treat tomato stem canker?
• How to prevent tomato stem canker?


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