Royal Horticultural Society
The ultimate in
gardening reference
from the world's
leading gardening
organisation
RHS minisite
Books:
Browse all RHS books
RHS series guide
Interactive extras:
Wisley experts Q&A
Floral wallpaper
Beautiful ecards
Gardening calendar
More gardening
About the RHS:
RHS History
RHS today
DK and RHS
RHS interview
Visit the Official RHS site

Avoiding pests and diseases
Chemical pesticides are not the only way of reducing the problems caused by pests and diseases

Pansy leaf spotCultural methods, which largely aim to prevent pests and diseases from occuring through good gardening practice, will not usually eliminate them altogether. However, they help to reduce the degree of damage and may sometimes make it unnecessary to resort to pesticides. Therefore even where pesticides are acceptable, cultural methods should always be considered as well. However, if you rely only on cultural controls and do not use chemical pesticides at all, you will often have to accept some damage.

Remove dead foliage to prevent disease infection

Remove dead foliage to prevent disease infection.

Hygiene
Remove dead and over-shaded leaves as these can easily become infected by diseases such as grey mould (Botrytis cinerea) which then spread to healthy leaves and flowers. They also harbour pests such as slugs and snails. Plants badly affected by pests and diseases are best removed if they are unlikely to make a quick recovery. If roots have been affected, carefully take away the whole root system and the immediately associated soil, to ensure that all traces of the pest or disease are removed.

Weeds
Remove weeds, as they compete for plant foods and water and therefore stress cultivated plants. They can also act as alternative hosts for pests, including aphids, red spider mite and whitefly, and for diseases.


Resistance
Many plants have some cultivars that are more resistant to disease or pest attack than others, especially in the case of diseases such as mildews and rusts. The resistance may be within the plant tissues or it may come as the result of a different growth pattern: for instance, some cultivars of Hemerocallis (day lily) flower later in the summer, allowing them to escape attack by gall midge.

Luring earwigs away from plants

Luring earwigs away from plants
To trap earwigs, fill flower pots with straw, and invert them on canes among susceptible plants. Inspect traps in the morning; remove any earwigs, and destroy them.
Rotation
Do not put the same types of plants in the same place year after year, since this will help soil-borne pests and diseases to build up. For example, the spores of downy mildew and leaf spot disease of pansies remain in the soil from the previous planting.

Traps
Some pests can be trapped, then removed or destroyed. For example, 'slug pubs' capture slugs or snails, and straw-filled flower pots attract earwigs.

Good cultivation
Finally, it is important to grow plants correctly with careful attention to planting, feeding, watering, deadheading, pruning, and propagation. Well-grown plants often stay healthy.


 RHS Wisley Experts Gardeners' Advice
 Planning small gardens
 Playing with colour
 Controlling slugs & snails
 Avoiding pests and diseases
 Ten easy vegetables
 

The information in this feature was taken from RHS Wisley Experts Gardeners Advice.

Payment methods on dk.com

Mastercard logo Visa logo Visa Delta logo Visa Electron logo Visa purchasing logo Amex logo Solo logo Maestro logo

© 2008 Dorling Kindersley™ Limited, Registered Number 861590
England, Registered Office: 80 Strand, London, WC2R 0RL.
Dorling Kindersley, DK and dk logo are registered and/or unregistered trade marks of Dorling Kindersley Limited.
PRIVACY POLICY | TERMS AND CONDITIONS