Table of Contents
- 1 The Gardener’s Little Helpers
- 1.1 The Advantages of this New Protective Technique
- 1.2 Exhibit line HM (Heterorhabditismegidis)
- 1.3 Garden Plants Perfect for Attracting Beneficial Insect Parasites and Predators
- 1.4 Predatory Ladybirds: Nature’s Solution to Aphid Control by Johan Gerber
The Gardener’s Little HelpersThe Gardener’s Little Helpers
Sweet little creatures… For professional greenhouse growers but also for amateurs with a veranda or greenhouse, there now exists an alternative to chemical products. There are in fact natural predators of insects which destroy our plants. Therefore, by using these little helpers alongside selective treatment we can cultivate responsibly and be more environmentally friendly. We call this ‘inbuilt protection’.
The Advantages of this New Protective Technique
- the elimination of chemical stress on the plant which is often weakened by sometimes repeated chemical treatment.
- it gets rid of the risks brought about by the handling and inhaling of these chemical products.
However, use of these predators demands an enclosed space to ensure that they are kept as close to the plants as possible.
The insects live together in harmony and are of no risk to humans. They are all natural entities which are of no danger to users, to consumers or to the environment. None of these insects stings people or damages plants.
The best-known helper is the ladybird larva which is an excellent predator of greenfly and is also an educational tool for children who love to follow its evolution.
The predators which are easiest for the amateur to use are:
Cryptoline M (this is a ladybird called Cryptolaemus Montrouzieri)
It attacks the floury and cottonous mealybugs or cochineal insects. It is presented in small flasks of 25 adults. Once installed after 2 or 3 introductions, the adults reproduce, and along with the adults, the larvae will continue to eat the mealybugs and clean the vegetation. These should be used especially by people with a lot of non-flowering plants like the ficus, the scheflera, the croton, etc…in fact, most non-flowering plants, but also flowering plants…Watch out for the larvae which are all white…don’t mistake them for mealybugs…
Encarline F (that’s the well-known Encarsia Formosa)
which mainly attacks the Trialeurodes vaporarium (one of the big varieties of aleurodes). It is presented on tiny cards on which are placed aleurode pupas which have already been interfered with by encarcias. From these pupas will come adult encarcias which will act as a parasite on and destroy the existing aleurode populations. This product is inexpensive, and for it to be efficient, it should preferably be used as a preventative measure or on small numbers of aleurodes. If the population of aleurodes is too big (high infection) a compatible phytosanitary product should be used beforehand (and for amateurs the phyto choice is not an easy one..). It should preferably be used by people with a lot of fuschias, primaveras, lantanas, gerberas, etc…
Aphaline Ice-mix (Aphelinus abdominalis, Aphidius colemani and Aphidius ervi)
This is a mixture of 3 greenfly predators. There are many varieties of greenfly which cannot be dealt with by one sole predator. This cocktail is capable of dealing with most of the greenfly varieties. This is presented in a small bottle containing adults, pupas and mummies about to hatch. To be used on all tender and growing plants, which are particularly appreciated by greenfly.
Phytoline P (Phytoseiulus persimilis)
This is a small acarid which attacks tetranychus acarids (yellow and red spiders). It eats them at all stages of development. This predator should be used at the first sighting of these parasites on all plants…palm trees, etc….
Exhibit line HM (Heterorhabditismegidis)
contains roundworms which will interfere with, infect and kill weevils with a bacteria called Xenorhabdus. This product is the only one that can be used outdoors, but preferably in containers or pots. All ornamental garden plants can be attacked by weevils (damage can be seen mainly on leaves).
Garden Plants Perfect for Attracting Beneficial Insect Parasites and Predators
I thought it might be appropriate seeing that spring has arrived to advise on plants very much needed to create breeding and feeding sites for Nature’s pest controls. Most probably the most effective way of restoring nature in your garden is to include as many small and bigger nectar flowering plants as possible. Beneficial insects should be viewed as mini-livestock. They will be healthier, reproduce more readily, and be more effective biological controls when their habitat is provided with an adequate and easily available diet of nectar, pollen, and herbivorous insects and mites. However, this is not a magical cure for pest problems. It is simply an ecological approach to pest management that can be integrated with modern technology in controlling pests with commercially available, selected pesticides. There are many flowering varieties to choose from.
Some of the plant varieties that are known for attracting beneficial insects include wild rocket, coreopsis, fennel, dill, tansy, mustard, Shasta daisies, alyssum, candytuft, cosmos, garlic chives, Euryops yellow, marigold, coriander, goldenrod, Queen Anne’s lace, crimson clover, buckwheat, red heart poker, sunflower, chrysanthemum, various grass varieties, and roses. You will find that one of the best color flowers to have for attracting many species is yellow, or any color with a touch of yellow in it.
Include most of these plants in your garden (the wilder the better) and you will establish an amazing ecosystem within your garden, big or small. Quite often you need to tolerate an aphid infestation on your roses for awhile to be able to see the strong build-up of ladybirds and many other beneficial insects. Have a close look on your flowers to see if you can spot beautiful flower crab spiders, look inside permanent plantings like conifers, Acacia spp, and other trees and shrubs. You will find a huge number of wonderful creatures including praying mantids, larva and adult ladybirds, parasitic and predatory wasps, flower spiders, assassin bugs, tachinid flies, hoverflies, bee flies, lacewings, and on the garden floor, ground beetles.
Predatory Ladybirds: Nature’s Solution to Aphid Control by Johan Gerber
With spring around the corner, it is time to make sure that gardeners are going to follow healthy gardening practices to enhance and conserve Nature’s biological controls. Starting with predatory ladybirds, one might assume that all ladybirds are beneficial. Unfortunately, there are a few non-beneficial species which are plant-eating. The potato ladybird is quite often mistaken for its beneficial look-alike, the lunate ladybird. Beneficial ladybird species do not cause damage to leaves like the potato ladybird and the sweet potato ladybird.
Although cypress aphids do a great deal of damage to conifers, there is a positive side to the infestations in my garden. Aphids attract beneficial insects such as ladybirds and praying mantids during the winter months. I am always delighted to see ladybird couples mating in June and July in the dense foliage of my golden rocket which tends to become badly infested with cypress aphid. The challenge is to reduce the cypress aphid population without killing the ladybirds and praying mantids.
It is always good to allow a small number of aphids to survive on your plants in the garden. I have found that the best way of controlling severe infestations of aphids without affecting healthy numbers of beneficial ladybirds on my roses is to remove part of the serious aphid-infested new shoots or growth. Once the shoots and flowers mature, the aphids leave anyway. When these aphids or any of the other food sources leave the plant, the ladybirds also leave. Therefore to ensure healthy populations of beneficial ladybirds you need to make sure that host plants of aphids are maintained or alternative prey such as mealybug and red spider mite are still around.
Plants associated with beneficial ladybirds are fennel, dill, tansy, bishop’s weed, angelica, Queen Anne’s lace, goldenrod, coreopsis, cosmos, dandelion, sunflower, crimson clover, hairy vetch, grains and indigenous grasses, buckwheat, butterfly weed, anonymous, rye, Hemp sesbania, soapbark tree and buckthorn. Most of the beneficial ladybird species in my garden visit the roses, golden rocket, sunflowers, lemon geranium, coreopsis, hibiscus, cosmos, Shasta daisies, and wild rocket.
The control of ants nesting in the soil around plants will help beneficial ladybirds control their prey more effectively. Ants, especially pugnacious and other ‘cocktail’ ant species, protect insects such as aphids against natural predators in return for honeydew. If you do use an ant control formulation, do not spray the plants but rather pour diluted spray mixture down their nest entrances.
Avoid the use of any insecticide, chemical or organic, that contains active ingredients for the control of beetle species such as a stylus, CMR, flower, chafer, snout as well as stinkbugs. Many insecticides containing cypermethrin, deltamethrin, permethrin, bifenthrin, alpha-cypermethrin, chlorpyrifos, mercaptothion, gamma-BHC, fenitrothion, cyfluthrin, nicotine, rotenone, and natural pyrethrins might kill adult ladybirds on contact
The following active ingredients used in insecticide formulations are harmless or unlikely to harm beneficial ladybirds: Bacillus thuringiensis subsp. israelensis for fungus gnat and mosquito control; Bacillus thuringiensis var. kurstaki for the control of leaf-eating caterpillars; spinosad for thrips, African (American) bollworm and leaf miner control; garlic and essential oils used as insect repellents; etoxazole for red spider mite; pyriproxyfen for whitefly; potassium salts of fatty acids and canola oil for small soft-bodied insects and natural pyrethrins used as a nest treatment for the control of ants and wood-eating termites. Insect traps designed to be used with sex attractants (pheromones) will have no adverse effects on predatory ladybirds unless it comes in accidental contact with a sticky liner or insecticide-treated baits used. These traps and pheromone will soon become available for use in home gardens.
Baits containing fipronil for harvester termite control as well as granular baits for snail, slug and cutworm control will not affect ladybird populations adversely. Fungicide formulations containing plant organic acids, mancozeb, chlorothalonil, procymidone, Trychoderma spp., copper-based formulations, and soil-applied microbial formulations will not harm ladybirds when used as directed.