Q.Is Blossom Set Spray Safe For Bees
I want to encourage fruit to grow on my beautiful winter squash so I bought blossom set spray but it doesn’t say on the label if it’s safe for bees. It has numerous warnings for if it gets on your skin and eyes so it sounds dangerous! I do t want to do more harm than good
Certified GKH Gardening Expert
Because of the nature of cytokinins (it causes rapid cell division) it is listed as quite toxic to mammals. It is notorious for causing various cancers in humans if not used properly.
Usually, it is marketed for tomatoes, since bees do not pay much mind to them. They are wind pollinated, or self pollinated, typically.
It is supposed to be safe for insects, but it isn't clear if this is due to lack of study, or actually being non-toxic to them. Some insecticides contain a small amount of the substance.
With all of that being said... It is very water soluble, and washes off quite easily. It will be taken up by the plant very quickly, and whatever does not will get washed off by the next water or rain.
This substance is, currently, the best thing to use when pollination cannot, or should not occur. (Think seedless grapes).