Remedy for cabbage worms
I stumbled upon quite a library of gardening books on Google documents. One book "1000 Hints on Vegetable Gardening" by M.S. Croy, pub. in 1917 states"
"The cabbage worm which infests cabbage and cauliflower can be eliminated by a solution of one ounce of saltpeter dissolved in three gallons of water One spraying will nearly always be enough at least until another crop of worms have a chance to gather and the saltpeter will not turn the cauliflower heads dark"
Has anyone heard of this remedy? If so, does it work?