Close-up photograph of fine water droplets beaded across the upper surface of a waxy green leaf, each catching a highlight, the water plainly sitting on top rather than soaking in.

Thrips Never Seem To Go Away

Karen Horn

Not on the underside — inside it. Which means that when you sprayed, a large share of the thrips on that plant were sealed in plant tissue or sitting in the potting mix, where nothing applied to a leaf goes. They were never killed, and they arrived on schedule.

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