Disease*

Harm Caused

How Common

Difficulty of Control

Total

Nutrient Deficiency

Causes a range of symptoms depending on the deficiency.
(Score 8)

Common.
(Score 8)

Once identified easily remedied by replenishing deficient nutrient.
(Score 8)

24

Camellia Flower Blight

Flowers of Camellia prematurely brown off and drop.

(Score 5)

Very common.
(Score 9)

Fungicides are not effective.
(Score 9)

23

Powdery Mildews

A fungal disease affecting many different plants.
(Score 8)

Very common in warm humid conditions.
(Score 9)

Relatively easily controlled with fungicides.
(Score 6)

23

Rusts
(inc Myrtle Rust)

Cause twisted, distorted leaves and shoots.
(Score 7)

Common on a wide range of host plants.
(Score 8)

Can be controlled through the early application of fungicide and cultural controls.
(Score 7)

22

Peach Leaf Curl

Causes leaf curl and premature drop affecting crop yield.
(Score 7)

Common.
(Score 7)

Prevention through winter spray programme required.
(Score 8)

22

Cankers

Affect the stems and branches of trees and shrubs.
(Score 8)

Common in wet weather and when limbs are damaged.
(score 7)

Can be controlled through the early application of fungicide and cultural controls.
(Score 7)

22

Root Rot

Causes severe dieback of trees, shrubs and other plants.
(Score 8)

Common when soils are waterlogged.
(Score 6)

Can be controlled through the early application of fungicide and cultural controls.
(Score 7)

21

Bacterial Disease

Cause a variety of symptoms.
(Score 7)

Less common than fungal diseases.
(Score 5)

Difficult to control.
(Score 9)

21

Viral Diseases

Can cause serious or mild symptoms.
(Score 7)

Rarely a problem in home gardens.
(Score 5)

Once infected little can be done.
(Score 9)

21

Psyllid Yellows
(inc zebra stripe)

Yellowing of tomato and potato foliage and affects tubers and fruit.
(Score 7)

Not common.
(Score 5)

Requires prevention of infection from psyllid insects.
(Score 9)

21

Red Thread

Causes mottled brown patches on lawns.
(Score 6)

Common in damp conditions.
(Score 8)

Responds to lawn fungicide and addition of nitrogen fertiliser.
(Score 6)

20

Buxus Blight

Causes dieback of Buxus.
(Score 7)

Common.
(Score 7)

Can be controlled through fungicide and cultural controls.
(Score 6)

20

Downy Mildew

Fungal disease of the foliage of many plants.
(Score 6)

Common in damp conditions.
(Score 8)

Can be controlled through fungicide and cultural controls.
(Score 6)

20

Leaf Spots

Fungal disease of the foliage of many plants. Not often severe.
(Score 6)

Common in wet conditions.
(Score 8)

Relatively easily controlled with fungicides.
(Score 6)

20

Sooty Mould

Black mould growing on leaf surfaces. Can shade light from the leaf.
(Score 5)

Very common where plants are infested with sap-sucking insects.
(Score 7)

Requires control of sap-sucking insects.
(Score 8)

20

Fire Blight

Bacterial infection of pipfruit and shrubs.
(Score 7)

Not common.
(Score 5)

Prevention through winter spray programme required.
(Score 8)

20

Clubroot

Causes swelling and stunting of roots, particularly brassicas.
(Score 7)

Not common.
(Score 4)

Once infected little can be done.
(Score 9)

19

Grey Mould

Affects leaves and fruit of plants in warm moist conditions such as greenhouses.
(Score 6)

Common in densely planted greenhouses.
(Score 6)

Can be controlled through the early application of fungicide and cultural controls.
(Score 7)

19

Sclerotinia

Causes wilt and rots of herbaceous plants.
(Score 7)

Not common.
(Score 5)

Can be controlled through the early application of fungicide and cultural controls.
(Score 7)

19

Over Watering

Plant roots unable to absorb oxygen and nutrients causes dieback.
(Score 8)

Common in waterlogged soil.
(Score 5)

Improve drainage.
(Score 5)

18

Brown Patch

Causes circular brown patches on lawns.
(Score 6)

Not common.
(Score 5)

Responds to lawn fungicide.
(Score 6)

17