Before using an adjuvant with a pesticide, check whether one is needed or would negate the main product. For example,
- Some insecticide products such as liquid BT and Spinosad are very good penetrants on their own and addition of a penetrant or surfactant can have poor results
- Other insecticide products such as Ortho Tree & Shrub *Fruit Tree Spray and Voliam Flexi have a surfactant built in so there is no need to add another
- LI 700. Very good for enhancing herbicides. Otherwise I’ve discontinued it on cultivated plants because leaves show signs of toxic effects afterwards.
- Hi-Wett. Very effective. Typical dosage is 1 ml to 3 ml per gallon, the latter when rain is imminent.
- Neem Oil concentrate. Typical dosage is 1 ml to 1 tsp per gallon, the latter for better protection against rain.
Note that Neem Oil is not an effective pesticide, as shown in Organic Agriculture trials by the Farm Extension in San Diego county 20 years ago. It does not contain any viable quantity of insect toxin. It will slow down weak insects but those that survive breed more vigorous populations. As was recently stated by the California Dept. of Agriculture:
“The biggest threat to U.S. Agriculture today are mis-informed home gardeners”
If you want to control insect and arachnid pests on your property with a spray or broadcast product, make sure the listed active ingredients include an insect or arachnid toxin.