Posted: 17/05/2012 at 15:07
Yes, it's derived from Chrysanthemums. You wouldn't use it on baby seedlings - well, you wouldn't spray most things on baby seedlings. With crops, you can harvest the day after spraying. Washing the crop, obviously.
It only works on contact with the pest, it's not systemic - meaning it doesn't penetrate the plant and stay there for a lasting effect. Which means you have to respray if the pests return, if it rains, etc.
Or, if you want to make your own spray, the garlic spray is the classic home gardener's weapon against caterpillars and the like. There are literally dozens of recipes. I make a combined garlic/chilli spray. I toss a head of garlic, a couple of hot chillies, a couple of squirts of washing-up detergent, a glug of oil and 4 or 5 cups of water into a blender. Blitz, strain out all the solids, then add another cup of water. Pour it into a spray bottle with an adjustable nozzle, label it, and attack your pests. Again, it's only a contact spray. It doesn't have residual properties.
It's a bit pongy, but it works!