Guidelines for Control of Pests & Diseases
Prevention is better (and easier) than cure!
Inspect your plants frequently to detect AND treat pests and disease early.
Feed your plants to increase resistance and repair capabilities.
Avoid overcrowding – do not grow more plants that you can handle.
Ensure adequate ventilation.
Avoid overwatering – water in early morning. At temperatures higher than 30°C plants absorb and transpire water with difficulty and excess watering may drown plants. Mist or dampen floor, encourage ventilation. Look at weather reports and prepare for a hot day! Young plants in large pots are vulnerable!
Never let the root ball dry out completely – the hair roots die first and water cannot be absorbed – risk of drowing – water from underneath (saucer) and mist spray.
Hygiene – remove all dead/dying/diseased plant material soonest. Clean pots with a disinfectant like Jeyes Fluid before re-use.
Adjust temperature and humidity – where possible – some pests like it hot and dry (Whitefly and red spider mite), some like it cold and wet (rust and botrytis) – make them uncomfortable!
Pruning with defoliation in autumn will remove all pests and diseases.
Many pests are brought in by new plants – quarantine new plants for a few weeks.
Precautions when spraying en masse:
Protective clothing – long sleeved shirt, long trousers, masks, cap (if bald!), glasses or goggles and gloves allow you to pick up plants to spray underneath leaves. Cleanse and rinse spraying apparatus, change/wash clothing and shower. Store in safe place, in original labelled containers.
Remember wet sprays mark flowers and buds. Ensure a pest-free environment well before the show – USE PREVENTATIVE SPRAYING.
Spray in early morning or evening when there is less wind and it is cooler – catch the beasties napping! Spray downwind if there is a breeze! Spray for total coverage under and upper surfaces of leaves, and stems, but don’t make them dripping wet! Do not spray just before rain is expected.
Read instructions carefully – the recommended does is what works! An insect needs only to be killed once, and you risk damage to your plants! Useful insects may also be killed.
For a few plants use one of the insecticide/fungicide ‘GUNS’, but still be careful.
Contact insecticides/fungicides only work on contact and often only kill the adult pest, but do give quick results – spray several times at intervals of 4-5 days to catch successive generations before they can breed.
Systemic insecticides and fungicides are watered into moist soil or sprayed on foliage, taken up by the roots/leaves and make the sap poisonous to the pests. Efekto insecticide granules are an alternative. They give more prolonged protection, but act more slowly.