Canola oil is one of the effective organic pesticide used to kill/repel insects. First you need to prepare 'concentrate' by mixing two cup of canola oil with two tablespoons of non-degreasing liquid dish soap in a plastic container and shake well. You can store this concentrate in safe place for long time.
Take one and half teaspoons of this concentrate and mix with one cup of warm water in plastic spray bottle. Shake it well and spray on plants. Spray when plant surfaces are dry (better during morning or evening hours). Don't spray during afternoon or during high temperature to avoid degradation of canola oil. The spray should cover both leaf surfaces, stem and petiole. Repeat the spray every seven or ten days to control insects.
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