|
Back to National Dahlia Societies Home Page
|
|
Key to Dahlia Pest & Diseases
|
|
Back to National Dahlia Societies Home Page
|
|
Key to Dahlia Pest & Diseases
|
Flower problems
Flowers and/or buds shrivelled and with fluffy grey Grey Mould = Botrytis
Flowers with mass of mites covering bloom (Generally seen when bloom brought into the House for decoration purposes) = Red Spider
Flowers with tattered petals = Earwigs
Flowers with light flecking on petals, many small long-bodied winged and wingless insects’ present = Thrips
Flowers with irregular holes and pieces eaten away and slime trail present = Slugs and Snails
Flowers with holes (Centre of bloom) and petals with pieces eaten away; no slime trails present on or near flower = Caterpillars
Foliage problems
 Picture illustrating virus. The plants in the background are of the same cultivar.
|
 Picture illustrating sever Red spider attack |
Dahlia Smut |
Leaves with numerous pale spots = Smut
Leaves variously crumpled with irregular, pale yellowish patterns with insects visible more so with a magnifying glass = Red Spider
Leaves variously crumpled with irregular, pale yellowish patterns with no insects visible with a magnifying glass = Virus
|
|
Leaves wilt; stem interior with brown or black streaks = Wilt
Leaves with irregular holes and pieces eaten away with slime trails present on or near plants = Slugs and Snails
Leaves with irregular holes and pieces eaten away; no slime trails present on or near plants = Caterpillars
Leaves with small tattered holes, especially at tips of shoots; buds sometimes killed = Capsid Bugs
Leaves, shoots and flowers infested by colonies of black, green or yellow wingless and winged insects; Foliage sticky and sometimes sooty =Aphids
Stem with soft, irregular swelling = Crown Gall
Stem base rotted; cottony white mould growth present = Sclerotinia Disease.
 Picture illustrating Crown Gall, here on a stored tuber although the tuber showed no physical signs until it began to shoot. |
