TROPO's Organic Info Library

Home-Made Sprays*

Home-made organic sprays have been used for centuries to control pests and diseases. The recipes given below were compiled for TROPO by Graeme Eggins and come from various sources. He suggests that anyone interested in trying these sprays should make up and trial a small batch first, before preparing and spraying on a large scale.

Remember that sprays of any kind, organic or conventional, should be seen as only part of a pest and disease management program and should never be over-used. Also consider biological and other controls, including those discussed on other pages here.

Some organic sprays are quite toxic to people, so heat ingredients in glass or enamel containers, not your household cooking pots. Store in glass or ceramic containers labelled DANGER and well out of the reach of children. Better, make only as much spray as you need at one time.

General Insecticide Sprays

Garlic spray: Soak 125g of minced garlic in 40ml of mineral oil or kerosene. Leave to soak for two days to extract the garlic oil. Then add 500ml of water and 10g of grated Sunlight or similar pure soap and mix well.

Strain and store in plastic or glass. To use, dilute one part garlic mix to 50 of water. Repeat spraying after rain.

Organic mix: Boil together a handful of tansy, rhubarb leaves, mint and several garlic cloves. Strain, then add a little liquid pure oil-based soap. Make sure to spray under leaves.

Bug juice: Collect a good handful of the insect pests that are causing damage. Put them in a kitchen blender with water at the ratio of about one part bugs to two parts water and blend at high speed till the insects are reduced to a misty pulp (usually takes about one minute). If you don't want to Use a blender, a paint stirrer in an electric drill works almost as well.

Strain mix through cheesecloth or similar material. Dilute 'the juice" with four times as much water. Use liberally. Repeated applications may be necessary to deter problem bugs.

Pyrethrum spray: Dry pyrethrum flowers (Chrysanthemum cinerariaefolium) as soon after harvest as possible to retain active ingredients. Soak flowers for 24 hours in enough kerosene to cover. Filter and store can be stored up to 6 months. Dilute 10 times before use.

Remember pyrethrum is toxic to most insects on contact, including beneficial ones (eg bees) so use with great care. (Also toxic to humans and other mammals. Although less so than to insects.)

Derris spray: Mix 60m1 Derris dust with 30ml (40ml Codacide oil and add 20 litres water. Use with great care as this is also toxic to a wide range of non-target insects, and other species including humans.

Suffocating Sprays

Many small insects, especially thrips and aphids, can be suffocated by being sprayed with a weak solution of water soluble glue. Fine clay mixed with water has a similar effect but tends to clog spray nozzles.

Sap sucker sprays

Lantana/woodworm spray: Boil 500g of lantana leaves in 1 litre of water- for 20 minutes. Cool and strain. Spray liberally on affected plants. Most effective against aphids. A stronger spray can he made by substituting wormwood for lantana.

Rhubarb Spray: Simmer 500g chopped leaves in one litre of water for 20-30 minutes in a glass or enamel container, then cool and strain. Dilute at 1:100 with water and spray. Take care as rhubarb spray will kill predators and beneficials like bees. It has a minimum withholding period of two days on fruit and vegetables.

Elder spray: Boil 500gm of elder leaves in 1 litre of water. Let stand till cool, strain and store. Use undiluted.

Plant Tonics

Collect comfrey leaves or stinging nettles (amount is up to you), place in a container, cover with water and leave until the water turns pale brown or green. Strain and dilute 2: 1 with water and spray as a foliar fertilizer and tonic. The mix also helps control aphids.

Alternatively, use manure, compost, seaweed and non seedling weeds to make liquid manure. Fork the material into perforated sack or box made of chicken wire and hang inside a clean metal drum. Suspend sack or box by a rope tied to a stick placed across the top of the drum. Fill with water, cover from rain and leave till the water turns brown. Dilute to the colour of weak tea before using, and apply only when the ground is damp following rain or irrigation.

Music: Not exactly a spray - but a number of growers overseas play music to plants to stimulate their growth and deter damaging insects. The book Secrets of the Soil (reviewed in Going Organic No, 6) reports on tests where scientists played Vivaldi to plants to increase yields.

Australian writer Jeffrey Hodges, in his book Natural Gardening and Farming in Australia, says the types of music he has found most suitable for playing to plants include Gregorian chants, Baroque and Medieval music and New Age music by people such as Steven Halpern and Brian Eno.

Some overseas experiments indicate that it may not be the melody but high frequency sound waves that promote growth.

Fungicides

Bordeaux mixture: This is a standard organic fungicide used to treat a wide range of rots, mildews, and blights. Mix 90g of copper sulphate (bluestone) with 4.5 litres of hot water in a non metallic container and leave overnight. Next day mix 125g slaked lime with 4.5 litres of cold water in a non metallic container. Combine both mixtures by stirring vigorously. Use immediately. An oil like Codacide can be added to increase its effectiveness.

Bordeaux spray may clog nozzles. Also, if over-used, it may lead to a build up of copper in the soil and associated toxicity.

Chive tea: Cover a good handful of chives with boiling water and let stand till cool, Strain and spray. Useful against downy mildew on cucumbers, pumpkins and zucchini.

Milk mix: Mix equal quantities of water and milk and spray as mildew preventative. A spray of one part milk to nine of water sprayed every 10 days is used to treat mosaic disease on tomatoes, cucumber and lettuce.

Seaweed spray: A strained seaweed liquid manure is a mild fungicide. Don't apply in very hot weather.

Tree paint: Mix copper oxychloride at the rate of 100gm a litre with flat white plastic paint. The paint will turn green. This can be used to protect tree butts injured by slashers and other machines. Trees are particularly open to fungal attack from December to May on the North Coast.

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