Off The Shelf Pest Control
The range of
low toxic, off the shelf pest control preparations available to gardeners is
expanding. Here are some of the main products/ingredients available.
BT - Also sold as Dipel, this naturally occurring bacteria (Bacillus thuringiensis)
controls some types of caterpillars. It has been cultured and
is available in a powdered form that is mixed and sprayed on to plants.
CONDIES CRYSTALS - (Potassium
permanganate) A few drops in a bucket will turn the water pink. Controls powdery
mildew and is used by some gardeners to kill ants in potted plants. It is toxic to
COPPER SPRAYS - Copper
oxychloride, cupric hydroxide and Bordeaux mixture are used to control a range
of fungus diseases including mildews, anthracnose and leaf spots.
DERRIS DUST - Derris is made from
the ground root of the
rotenone plant (Derris elliptica). It is used to control
chewing insects. While it is allowable under organic growing regimes it is toxic
to worms, but some gardeners do use it for lawn grub control.
DIATOMACEOUS EARTH - Composed of
the ground tiny salt-water organisms called diatoms, insecticide grade diatomaceous earth has
microscopically sharp edges that desiccate insects on contact or kill them when
ingested. The fine grey powder is mixed with water then sprayed on to plants.
Please note that the diatomaceous earth used in swimming pool filters is heat
treated and cannot be recommended for use in the garden.
HORTICULTURAL GLUE AND BARRIER
PAINTS - These products are applied to the trunks of trees to
prevent insects making their way up into the foliage canopy. They are
particularly effective against ants, preventing them transporting scale,
aphids and other insects from overcrowded colonies located nearby to clean
plants. They can act as effective barriers to a range of caterpillars.
NEEM OIL - Neem
oil has a long history of use in countries like India where it can be
found in everything from soap and toothpaste to pest control products.
Eco-neem is a naturally-derived botanical insecticide that
contains a highly stable and effective extract from
the neem tree. eco-neem controls caterpillars, lace
bugs, aphids, whiteflies, beetles, mealybugs, scale,
mites, fungus gnats, grasshoppers, leafminers and
OIL BASED SPRAYS
derived from petroleum such as white oil and PestOil are frowned upon under
organic certification. Fortunately, it is possible to make up your own
vegetable based oil spray (see
Do It Yourself Control). Oil sprays
are great for controlling a wide range of insect pests including scale,
mites, aphids and citrus leaf miner. Commercial products such as EcoOil
contain plant based oil and are a better choice.
- Exciting news for gardeners on the disease control front with the official
registration of Australia’s first organic fungicide. EcoRose (based on
has recently been released as the home garden version of EcoCarb.
It is exactly the same product, but comes in a smaller
size for home garden use.
A broad spectrum fungicide that controls powdery mildew and black
spot, the new registration applies for use of the product on grapes and roses,
although it receives regulatory approval in the USA for a wide range of foliar
PHEROMONE TRAPS - A pheromone is
a non-toxic species-specific scent produced by the female insect to attract the
male. Pheromones are often used as the attractant in baits and traps. Products
available include Wild May and Eco-Naturalure for fruit fly control.
PYRETHRUM - Natural pyrethrum is
extracted from the flowers of Chrysanthemum cinerariafolium. It will kill
predators if used indiscriminately, so be sure to spray late in the day when
bees have returned to their hives. It is used for a wide range of insect pests,
particularly beetles. Synthetic pyrethroids or products in which natural
pyrethrum is mixed with piperonyl butoxide are not allowable under organic
SEAWEED SPRAYS - Foliar sprays
made from seaweed have been found to be very effective in reducing fungus
diseases that affect leaves and flowers. Seaweed extract also increases the
microbial activity in the soil. This activity helps to make existing nutrients
more available to plants. Seaweed also increases the ability of plants to cope
with extremes of temperature including frost and drought.
SOAP SPRAYS - Soap sprays break
down the waxy layer of the insect exoskeleton causing the insect to dehydrate.
Be sure to use pure soap and not detergent. Commercial products include
SULPHUR - Dusting sulphur and
wettable sulphur preparations are effective against mites and powdery mildew.
Products acceptable under organic growing regimes are constantly under review,
so always check with your local organic growing group or
[http://www.daff.gov.au/aqis/export/organic-bio-dynamic] before using any pest control product.
text contains an edited extract from my book, 'Organic Vegetable Gardening',
published by ABC Books, plus additional information). See