Natural Organic Pesticides For Green Gardening | Homemade Insecticide Sprays, with Only 2 Ingredients, it's Simple, Organic and Safe! by Pioneer Settler at http://pioneersettler.com/natural-organic-pesticides/
Killing Aphids with Soap. HOMEMADE INSECTICIDAL SOAP CONCENTRATE 1/4 cup grated soap (I use Fels-Naptha, but Ivory or other real soap - see above - will work) 4 cups hot water Stir soap into water until dissolved. Store in a jar until ready to use. To dilute for plant use: Add 1 tsp. concentrate per 4 cups (32 oz.) of water. Pour solution into a spray bottle. This soap is a contact poison - spray directily onto the aphids. It will not harm your plants.
In the Garden: How to Make Your Own Homemade Organic Insecticides and Pesticides ~ I want to try the basic recipe........1 1/2 tsp liquid soap to 1 qt. of water, optional: 1/4 cup of isopropyl alcholol.