Horticultural oils when used properly, are effective alternatives to synthetic pesticides. In addition, they simultaneously conserve nontarget organisms and decompose rapidly.
Follow these 9 simple rules to gain the most benefit from an application of horticultural oils:
1) Know what the target pest is and choose the proper seasonal oil. Contact an agricultural extension service agent if you need help on pest identification or choosing the right oil.
2) Choose oils with the highest percent, or at least 92% of Unsulfonated Residues(UR). Sulfonated Residues cause leaf damage, so the smaller the percentage, the more pure the oil is.
3) As always, follow label directions explicitly, including the use of safety equipment.
4) Use the lowest possible concentration.
5) Remember salad oil and vinegar come "unmixed" so keep your mixture agitated.
6) Apply summer oils to fully hydrated plants with dry leaves.
7) Apply oils only when target pests are present and be sure to conver the insect completely with oil.
8) Avoid spraying when beneficial insects are feeding on the target pests.
9) Spray only a small portion of the plant initially if you are unsure whether the spray will cause leaf damage.