was researching use of nettles for varroa control and came across the study below.
thought it warranted its own topic.
(link is forum i found it in, direct link to study PDF is on page)
_4. Conclusions _
The purpose of the present research was to determinate in the laboratory and in the field the effect of different plant infusions and extracts on honeybee colonies productivity. Studied supplements were nettle (Urtica dioica), Protofil, onion (Allium cepa), garlic (Allium sativum), thyme (Satureja hortensis), Echinacea (Echinacea sp.). Experimental groups were build out of artificially weaken bee colonies. Laboratory determinations show different polyphenolic content in the studied plants, which were correlated with the field experiments regarding the production of brood surface. If we make a classification of the used supplements, regarding the growth of brood surface comparing to control groups, we can say that nettle infusion induced the highest growth, followed by Protofil, garlic, onion, Echinacea and thyme.