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Environmental Issues
Going Green

By Alan J Hartley

Biological And Non Chemical
Pest Control In The Garden



In Nature just about everything is preyed on by something else and using this simple fact is a very "GREEN" and natural way of controlling garden pests. It is not always the case though that little things are killed by bigger things. In the case of two of the gardeners friends, the Ladybird and the Frog/Toad it is true, but there are some very small animals called nematodes that will do an excellent job of killing many garden pests. Bigger than Bacteria, but smaller than Parasites like Ticks or fleas, Nematodes actually enter into the body of their host prey and kill them from the inside. Various different Nematodes can be bought, by mail order, to deal with most common pests such as slugs and Gooseberry Sawfly. The Nematodes arrive in a small packet in a dormant state, but can easily be applied by mixing with water and spraying over the affected plants/area.

Ladybirds are a big natural predator of all aphids and will devour huge numbers every day. They will appear in your garden as if by magic when the aphids start to multiply and become a real nuisance. Developing through several stages, as most insects do, Ladybirds could be considered the Swans of the insect world, as they have an ugly larval stage. On the rare occasion that you may have seen them, you probably would not have associated the large, ugly, horned grub, as being the beautiful Ladybird that we all know. Unless you have a big greenhouse it is probably not really worth buying packs of Nematodes, but you could always hunt around the garden and catch a few Ladybirds in your hands before transferring them to your greenhouse.

Ladybirds are of course one of many Beetles, that as natural predators, should be encouraged. This is a simple thing to do as many insects will over winter in, and are drawn to, log piles. So, if you do any heavy pruning donít burn or throw the logs away, but instead make a small pile in an out of the way part of your garden, or under a large bush. You can even buy ready made, small insect boxes to encourage them as well, in the same way that you would buy a bird box.

Some might think that a compost heap near to your greenhouse is not a good idea as it will encourage slugs, but on the other hand the compost heap will most definitely encourage many predatory insects as well as frogs and possibly even toads or newts. These are all very worthwhile little creatures to have patrolling your greenhouse on the look out for all manner of pests.

In some instances you can use plants to deter insects from attacking other plants that are near them. This is called "Companion Planting." Basil plants grown amongst tomatoes are said to prevent infestations with aphids, mosquitoes and thrips. In fact most of the herbs, including Rosemay, Dill, Sage and Chives can be used to deter many insect pests. Another old fashioned idea is to plant rows of carrots and onions alternately. The Carrot Fly is deterred by the presence of the Onions and the Onion fly is deterred by the presence of the Carrots. Cabbages benefit from being planted near Clover and other plants such as Marigolds can also be used as natural deterrents for various insect pests. Some plants go further and not only deter insects, but are actually toxic to them. Chrysanthemums have been used for centuries to create an insect poison called Pyrethrum.

A few plants can also be used to deter larger pests such as Chervil for slugs. Elderberry leaves or twigs pushed into mole holes are said to work wonders and it is even claimed that Garlic planted liberally in a garden will deter Deer!

All sorts of harmless things can be used to deter garden pests besides natural predators or plants and instead of using poisonous pellets. Gravel and egg shells are old favourites, as is placing a cup, with a little beer in, by your plants. The sweetness of the beer will attract the slugs that will drown in it. A modern commercial idea to deter slugs and snails, is to put self adhesive copper tape around each tub. For some reason slugs will not crawl over copper. One alternative to using chemical sprays and the like in the greenhouse, is to buy the sticky yellow cards that hang up on a hook in the greenhouse. Their natural sticky coating and yellow colour attract all manner of insects that will then get permanently stuck to them. Every few weeks you simply replace the cards when they have too many dead insects on them.

Many people like having cut flowers in the house, but are put off from cutting things like Dahlias especially, because they attract Ear Wigs. One old fashioned way of reducing the problem is to upturn a few old clay pots that have been packed with straw and "Plant" them on the end of canes amongst your Dahlias. The idea is that the Earwigs will congregate in the plant pots instead of the flowers.

Other commercial, but non chemical deterrents, in the form of various traps, can be bought to deal with things like Wasps that can be a real nuisance when the plums and pears begin to ripen in late summer. You can also buy fibre collars to put round your Cabbages and prevent them being attacked by cabbage root fly.

Larger pests such as Moles can be deterred by all sorts of commercial gadgets and ideas these days instead of just trapping or poisoning them. One of the more scientific devices is sonic and relies on the fact that moles have exceptionally good hearing. Humans can't hear the high pitched wine of the device, but Moles don't like it and are driven elsewhere. A simpler idea is to constantly pour water down their holes, or try the old fashioned idea of putting Moth Balls in them. Moth Balls are also said to deter Cats as well, because of their strong smell. Whatever you do though, don't plant Cat Mint as it will have the opposite effect because cats love it! Lion dung scattered round the garden is another even more exotic deterrent - if you can get it!



Gardening Tips
By Mrs FM


Unusual & Old
Fashioned Fruit


Herbs & Other
Edible Plants.


Books By
Alan J Hartley