Hi Saket,
I would not use glass material as leaves cause under different angles the glass material behave differently, see this https://radiance-online.org//pipermail/radiance-general/2015-February/010726.html , instead use “trans” material.But in general point above (on) the leaves should b fine. Maybe you should look into PAR simulation, it was discussed several times on the forum.
Best
Peter Z