Brandon from Bartlett, Tn writes
Monterey Horticultural Oil can be applied to soft and armored scale on shrubs using a garden sprayer. Thoroughly cover the infested plant, making sure you completely reach leaf undersides, twigs and other parts of the plant infested with scales.Do not apply within 30 days of a sulfur application; avoid applications on drought-stressed plants, windy days and temperatures are below 32F or above 90F. Follow the product label for detailed application instructions. We advise that you test out the solution on an inconspicuous part of the shrub before applying it more broadly.
Answer last updated on: 03/01/2017