DISEASES & PESTS
*When using insecticides & fungicides, appropriate precautions should be taken such as protective clothing, gloves & mask.
The major scale pest is fly-speck scale (tiny, black dots on the leaves). Brown scale is also sometimes a problem. Treat by spraying with a systemic insecticide or dipping the plant in a solution of it. Commonly used ones are
Folimat, Confidor & Rogor. Confidor is a water based formulation with a relatively low toxicity. These insecticides move throughout the plant to control insect pests & attack the sucking insects from the inside. You’ll need to spray twice within a fortnight. DON’T USE WHITE OIL WHICH WILL KILL THE PLANT.
These sucking insects look like white cottony patches as they often form dense colonies. If only a few plants are affected, they can be treated by wiping with a cotton swab soaked with alchohol. If there is a wider infestation, spray with a systemic insecticide as for scale. They can also get into the root system - treat by drenching roots & mix with insecticide as above.
These occasionally damage the flower stems. Treat with an insecticide recommended for this pest eg Malathion. Some use heavily diluted washing up liquid.
Vase Rot (Phytophthera cinnamonii)
This is caused by too much water & lack of aeration around the plant. It causes the centre of the plant to rot. If caught early enough, this disease can be treated by
- Removing affected leaves
- Draining all water from the plant
- Drenching with a fungicide eg Mancozeb Plus. DO NOT USE COPPER BASED FUNGICIDES WHICH WILL KILL THE PLANT.
- You can also get other fungus spots on the leaves which also respond to Mancozeb Plus.
Best time to catch them is in the early morning when they are sluggish.
If you have a problem, the easiest solution is to flush the vase out once a week to break the breeding cycle.
Heavy Metals eg copper, lead & boron
The effects can look like vase rot. Can come from treated wood or water from copper pipes & gutters.