Garden Wisdom Blog — category: Insects Pests and Diseases

Club root is the thickening and distortion of the roots of Brassicas by the soil fungus Plasmodiophora brassicae. Roots are distended and swollen and may appear to be shaped like fingers or tumors. Infected plants will exhibit day wilting (wilting during the day, recovering at night), and general poor production. Root Brassicas like radishes and turnips may show black lesions. All Brassicas are prone to this fungal disease: arugula, bok choy, broccoli, Brussels sprouts, cabbage, canola, cauliflower, ching chiang, collards, cress, daikon, gai lan, horseradish, joi choi, kale, kohlrabi, mustards, pac choi, radish, rape, rutabaga, tatsoi, toy choy, turnip, wasabi,...

The Carrot Rust Fly [CRF] is a weak flying insect pest that feeds its young on 107 different plants in the carrot family, including carrots, celery, parsnips, celeriac, parsley, and dill. The insect (Psila rosae) earned its common name due to the rusty coloured scarring left by its larvae as they feed on carrots, rendering them unmarketable. The adult female CRF deposits her eggs in the soil near the base of the base of the carrot, and about one week later the larva hatches and begins to feed on the carrot root. Eventually the larva pupates (forms a cocoon) in...

Cabbage moth is the name given to the very common Small White butterfly (Pieris rapae) in North America. True Cabbageworms and Cabbage Moth introduced from Europe (Mamestra brassicae) are small and brown, but both types do the same type of damage. The female lays tiny white eggs (that turn straw yellow before hatching) on the underside of Brassicas. These can easily be seen and knocked off. Left unchecked these eggs hatch into medium-sized green catapillars which eat large holes in the leaves of Brassicas and members of the mustard family. Using floating row covers prevents the butterfly from landing and laying...

Known as greenflies in the UK, there are over 5,000 species of aphids worldwide. Fewer than 10% of known species are agricultural pests, but they are a genuine nuisance. Like whiteflies, aphids are classed in the order Hemiptera because of their sucking mouthparts. They range in size from 1 to 10 mm long and may be green, grey, or black in colour. Local species usually occur in large numbers along the stems and flower buds of a wide range of plants. Aphids feed by puncturing the outer cells of plants and sucking out nutrients. This robs the plant of the...

Planting a Bumblebee Garden by Brian Campbell Why garden for Bumble Bees? Bumblebees are a keystone species. This means much of our ecological system hinges on the survival of bumblebees. Not just native plants rely on these furry pollinators, but also many other organisms; over 250 insect species use bumblebee colonies for one or more of their life stages. We may not understand the contribution they make to our well-being but certainly without them we would notice big changes in plant and animal life. All bee species are in decline around the world. Bumblebees are no exception. Research in Britain...