Plant Rx: Wash well behind the leaves
For centuries, savvy gardeners used soap sprays to combat bugs.
Andrew Jackson Downing, a gardening celebrity of the 19th century (who would have designed New York City’s Central Park if his life had not been cut short in a steamboat accident), wrote in 1845 that a “wash of soft soap is very good for many purposes ... penetrates all the crevices where insects may be lodged, destroying them.”
Then, DDT and other harder-hitting, longer-lasting pesticides developed during World War II left soaps on the sidelines.
Yet here we are in the more environmentally conscious 21st century, and soap sprays are back in vogue — for the same reasons they fell out of favor. Soaps biodegrade quickly and are relatively nontoxic to most creatures (including us).
Pests on plants don’t always warrant calling out the sprayer, but when spraying is needed, soap may do the trick.
You could just douse your rose bushes with leftover, soapy wash water, an aphid remedy once popular among British gardeners. Or you could use soap more deliberately, dissolving some tincture of green soap or Ivory soap shavings into water to make up your own mix.
Plant Rx: Wash well behind the leaves: 13, 2012 photo, insecticidal soap is sprayed on an orchid plant in order ... 
This plant smells like vanilla. Amazing! (obviously not vanilla though, cos thats an orchid. ) 
mom calls the orchid "my plant" WTF
SC91 Orchid Plant Blc Ports of Paradise 'Green King' Pot Pack MEDIUM: 
SC91 Orchid Plant Blc Ports of Paradise 'Green King' Pot Pack MEDIUM: