Can I apply DE BEFORE plants are full size (as in, NOW)? I purchased DE "Filter Powder" made for pools but also labeled "Pure DE" -- gardening dept person said it's the same thing. Is it? As for the sprayer, can I use a pump sprayer I purchased to apply cleaning chemicals to my concrete? It has a 2-4 ft hose with small sprayer. I never used it so it's clean! Thank you so much!
Certified GKH Gardening Expert
Actually the one for pools is not really recommended for the garden. Generally, you want to look for and use the type listed as Food Grade on the label. You will also need to follow the label instructions carefully for application, though now should be fine as long as your plants are strong. The sprayer should be fine too. Here is more information on using DE: https://www.gardeningknowhow.com/problems/pests/diatomaceous-earth-insect-control.htm