52A is a reference to some recent British erotica, also very hot over here, at least with the ladies (?) 650+ requests!
Should have stuck to my original:
Botanist's garden is reactionary, but good for degree.
2D - think of "new", then 2 of them.
Children know what a taboo is.
The answer is also a common euphemism for that other "herb", which no president is likely to allow any time soon. (-;