Another interesting post, this time from http://wakeup-world.com/2011/12/06/extensive-list-of-organic-pest-c....
Below is just an extract - there are more suggested remedies and solutions to fight fungal infections on their page.
List compiled by Australian Organic Gardening
ORGANIC BUG SPRAY FROM ONION SCRAPS
You can make your own organic bug spray from kitchen leftovers! Simply save your onion skins, peels and ends then refrigerate in an empty margarine-sized tub or ziplock bag until the container is full. Once you have enough, place the onion pieces in a pail and fill with warm water. Soak for a few days, up to a week. You can keep this on the patio in the sun to steep but this is optional. After one week, strain the onion bits out and store the onion water in spray bottles.
Bury the onion bits around plants that are prone to aphids, spiders and other pests. Just spray both house and garden plants with the water to fight aphids and pests. You can also mix your garlic trimmings in with the onion pieces, bugs hate garlic too!
CURE FOR WHITE/BLACK SPOT (mildew)
Add *1 litre of FULL cream milk to an *8 litre watering can, watered on Roses or mildew attracting plants, will kill white/black spot
Make the oil spray by blending two cups of vegetable oil with one cup of pure liquid soap, and mix it until it turns white.
Dilute one tablespoon of the emulsion to one litre of water and spray all affected areas thoroughly. Do this during mild weather, because if it’s hot it may burn the plant’s leaves.
Scales shoot a sweet substance called honeydew. Ants literally farm the scale to feed on the honeydew. They’ll pick them up and they’ll move them all over the tree. Honeydew also leads to sooty mould, a black dusty fungus that grows over the leaves and stems. Controlling the scale will also get rid of the sooty mould.
If you only have a small amount of scale, scrape it off with a fingernail or toothbrush. Larger infestations can be controlled by spraying with an oil to suffocate them.
To keep APHIDS and OTHER PESTS off your roses: Finely chop 1 onion and 2 medium cloves of garlic. Put ingredients into a blender with 2 cups of water and blend on high. Strain out pulp. Pour liquid into spray bottle. Spray a fine mist on rose bushes, making sure to coat both tops and bottoms of leaves.
Chop 90 grams of garlic, cover with mineral oil let soak over night, strain, add 1 litre of soapy water and store in a glass jar with a sealed lid. Dilute one part garlic to 50 parts water for use in spraying.
ALUMINUM FOIL “FOILS” APHIDS
Use an aluminum foil much around the base of plants such as tomatoes. The reflection confuses the insects and drives them away.
3 hot green peppers (canned or fresh) 2 or 3 cloves garlic 3/4 tsp liquid soap 3 cups water Puree the peppers and garlic cloves in a blender. Pour into a spray bottle and add the liquid soap and water. Let stand 24 hours. Strain out pulp and spray onto infested plants, making sure to coat both tops and bottoms of leaves.
AGAINST INSECT PESTS
1. Soapy water (NOT detergent). Try to find one based on caustic potash, rather than caustic soda and mix well with water until frothy (you’ll need more soap in hard water areas). For aphids and other soft-shelled insects
2. Oil sprays suffocate insects. Boil 1 kg soap with 8L of oil, stirring until dissolved. Dilute 1:20 with water just before use. Spray on cool days only.
3. Tomato leaf spray (very poisonous). Cover leaves with water, boil and cool. Use immediately as a general insecticide.
4. Pyrethrum spray. Pick almost-open flowers of Tanacetum cinerariifolium and dry in a cool place. Cover a few tablespoons of flowers with cheap sherry, steep overnight and mix with a litre of hot soapy water. Cool and use within a few days as a general insecticide. Store in a dark place.
5. Wormwood spray. Infuse leaves in boiling water and leave for a few hours. Dilute 1:4 and use for sap-sucking insects.
6. Chilli spray – equal volumes chilli and water blended and sprayed fresh onto caterpillars. (Prevent contact with eyes and skin.)
7. Lapsang Souchong tea – a strong brew (1 tbspn in a pot) deters possums from nipping rose tips
8. Many other materials can be used to make insect sprays. Depending on what you have available, try -quassia, garlic, marigolds, melaleuca, parsnips, turnips, eucalyptus, larkspur, elder, white cedar (Melia azaderach) or rhubarb (Please note: larkspur, elder (except for ripe berries) white cedar and rhubarb leaves are all highly toxic to humans.)
To see more remedies, visit Wake Up World at http://wakeup-world.com/2011/12/06/extensive-list-of-organic-pest-c...