Organic Gardening

Organic Gardening

Many well established gardening practices such as composting, mulching and crop rotation are the basis of gardening natures way. Organic gardening is a technique that avoids the use of all synthetic fertilisers and pesticides. However this page follows a more pragmatic but environmentally friendly approach.

Recently the boundaries between ‘conventional’ and ‘organic’ gardening have become blurred as ‘conventional’ gardening adopts more of the sustainable principles of the organic way and ‘organic’ gardeners recognise that some natural pesticides are more toxic than synthetic ones.

Hence today’s natural organic gardeners use all the proven, good garden practices of composting, mulching, crop rotation and use animal manures for extra nutrition. They also select plants and varieties more suited to the soil, climate and season to ensure best results.

Soil

The key to organic gardening success is a good soil. The main function of soils is to hold a reserve of nutrients and water for plants. A good soil is one that holds nutrients and water in a manner in which plant roots can extract them easily. To do this soil should be open, aerated and drain freely of surplus water. However at the same time it should hold ample water for plants.

To do all this the soil should be high in organic matter i.e. compost or similar material. Hence the basis of organic gardening is to have a soil with lots of compost. Compost needs to be added every year to keep the soil in good condition.

Composting

Compost can be purchased in bags or you can make your own. Making your own not only provides an ongoing supply of compost but it also gets rid of most garden and kitchen waste. See our growing guide on ‘Composting’ for full details.

Crop rotation

This is an old, well proven means of avoiding disease build up in the soil. It is used in the vegetable garden and the annual flower garden. If the same crop e.g. tomatoes is grown in the same soil every year the plant health and yield will decline to a point where it is not longer worthwhile. This is because soil fungus diseases specific to that crop, build up to a high level and suppress growth. This problem can be avoided by rotating crops around the garden, so that any one type of crop is only grown in any one area for one year in four.

The plant groups are:

• Brassicas and leaf veges – Cabbage, Cauliflower, Broccoli, Brussel Sprouts, Swede Turnips, Silver Beet, and Lettuce.
• Legumes – Peas, Beans, Broad Beans.
• Root Crops – Potatoes, Carrots, Parsnips.
• Miscellaneous – Tomatoes, Cucumber, Zucchini, Pumpkins, Sweet Corn.

Fertiliser

• Organic gardeners use predominantly animal manures, such as pelletised sheep manure to provide additional feeding for plants.
• A high level of compost use, and animal manure, will lead to an increase in soil acidity.
• It is therefore advisable to apply an annual dressing of lime at about 300g per sq metre.

Plant protection

• The organic gardening practices outlined here will minimise pests and diseases. However there are still some problem pests, and some plants that are commonly attacked.

The following products are recommended for organic growers. Generally they are less effective than conventional sprays and more frequent spraying is necessary.

Insecticides

• Pyrethrum – an old favourite made from a daisy, kills most insects quickly on contact. There are no toxic residues and food crops can be harvested 1 day after spraying. On the negative side Pyrethrum has no lasting effect, therefore repeat spraying is required.
• Yates Conqueror Oil Insecticide – a refined mineral oil which controls many insects by smothering them and cutting off air supply. Oil is effective against small sucking insects especially aphids, mites, mealy bug and scale. Again repeat spraying is usually necessary to clean up bad infestations
• Insecticidal soaps—such as Yates Natures Way, and Tui Eco Pest, are effective against small soft bodied insects but repeat spraying is required
• Yates Success Naturalyte – made from a natural bacteria extract, is very effective against caterpillars and thrips
• Yates Mavrik is an environmentally friendly synthetic insecticide safe to bees and soft on ladybirds. Effective against sucking and chewing insects – caterpillars, thrips, aphids, white fly, vegetable shield bug, passion vine hopper etc.

Fungicides

• Yates Leaf Curl Copper Fungicide Spray – a good general purpose fungicide which prevents many diseases including Blight on Tomatoes and Potatoes; Downy Mildew on Roses; Leaf Curl on Peaches and Nectarines.
• Yates Lime Sulphur Spray – a good winter clean up spray for deciduous fruit trees. It controls over-wintering insects and fungus diseases as well as lichen.
• Yates Natures Way fungus spray contains sulphur and copper for broader control
• Tui Eco Fungicide controls powdery mildew with regular repeated sprays.
• Yates Greenguard is an environmentally friendly synthetic fungicide which is very effective against all common diseases.