At a Glance
- Warm sunny site
- Free draining soil
- Lots of compost
- Fertiliser – use animal manures such as pelletised sheep manure
- Plants – select strong disease resistant varieties
- Pesticides – use low toxicity environmentally friendly pesticides.
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 recognize 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.
How to Care
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 maintain 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 the information sheet on ‘Compost Making’ 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 product 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 pelleted 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.
Pest and Disease Control
The organic gardening practices outlined in this brochure will minimize 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
Growsafe Enspray 99 – 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
Grosafe Free Flo 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.
Grosafe Lime Sulphur – 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 both sulphur and copper for broader control.
Tui Eco Fungicide controls powdery mildew with regular repeated sprays.
Warning Caution
Many organic remedies sometimes recommended, are not registered or proven. Some are extremely toxic.
For example:
- do not use Neem Oil on food crops.
- for fruit and vegetables - check the Pesticide Charts (fruit and vegetables) for the organic or environmentally friendly product that is approved.
Pest and Disease-Resistant Plants
An important tool for the organic gardener is to grow predominantly pest and disease resistant plants.
There are a range of plants in all categories of gardening that are relatively resistant to major pests and diseases. Organic gardeners should focus on these species and varieties. Ask your garden centre adviser for help.
Some examples of disease resistant varieties:
Fruits
Apples – ‘Initial’, ‘Boujade’, ‘Liberty’, ‘Prima’, ‘Priscilla’, ‘Sir Prize’.
Vegetables
Grafted tomatoes, hybrid varieties.
Download our spray charts with Organic treatment solutions: