Nursery Raising And Transplantation

Pest controls

YOU MAY, FROM TIME TO TIME, think about using some type of pesticide in or around your garden. You will probably go to the garden centre nearest you and ask a staff member what to do about the leaves curling on your fruit tree, the green bugs on your roses, or some obvious damage to a plant. Of course, the level of knowledge of staff members at a garden centre or even a specialist nursery will vary. They may point you to a certain product and say this will take care of your problem. It may, or may not.

The use of pesticides is a science, one that has been made much easier for the novice with the constant work of chemists and other researchers working for manufacturers. But it still requires attention on your part. Some plant treatments may be effective at one time of the year, but ineffective at others. Some plant treatments may work on one plant but be harmful to another. Let's look at how pesticides work.

• Always wear protective rubber gloves when applying insecticide sprays.

The label will state what, if any, food plants may come into contact with the product. The label will state treatment times, and how long you must wait to harvest after treatment. All garden pesticides can be.

Synthetic insecticides

Some chemical insecticides work on contact, and others have a systemic action. Contact insecticides must come in direct contact with the insect to have any effect. Contact insecticides for garden use are sold as a dust, spray, liquid concentrate, or soluble powder. When using a contact pesticide, you must thoroughly treat all parts of the plant, because some insects live primarily on the undersides of leaves. Systemic pesticides are those that will travel throughout the plant. An insect feeding on any plant part will ingest the systemic chemical that will kill it.

It is possible for some pests and fungal diseases to build up an immunity or tolerance to chemicals, so that a pesticide that was once effective no longer works. Continual use of the same chemical is not to be recommended. Different insecticides contain different active ingredients, so it's a good idea to rotate these regularly. All pesticides are poisonous to people, animals, and birds, and some will harm beneficial insects.

Synthetic herbicides

It is quite tedious to pull out weeds over and over again. Many gardeners find it easier to use a herbicide or weed killer to do the job. There are four common types of synthetic herbicides: pre-planting, pre-emergent, post-emergent, and sterilizers.

Pre-planting herbicides are used after you have prepared the soil, before you plant your seeds. They destroy weed seeds in the soil. After you have followed the directions, plant the seeds. Pre-emergent herbicides are used to destroy seeds as they germinate. They do not affect established plants or weeds. Post-emergent herbicides are used after the grass or other plants are established and you want to eliminate growing weeds. These products, usually sprays, may kill any plant on which they land. Sterilizing herbicides kill all plants they come into contact with. If sprayed on a plant, they will kill the leaves and then attack the roots and kill them. Avoid using these on a windy day.

It is extremely important when considering the use of any pesticide in a garden.