Spring Rhododendron Update (Post Winter Wilt-Pruf Application)

Back in December, I posted about an experiment that I was conducting with the application of Wilt-Pruf to one of our Rhododendrons that are located on either side of our back stoop.  Wilt-Pruf is an anti-transpirant that I bought to use on our fresh-cut Christmas Trees, but I also learned can be applied to any evergreen in an attempt to help it get through difficult Winters. 

Wilt-Pruf is a natural product made of pine oil and creates a clear, almost flexible coating on the leaves and needles.  

I sprayed it on just one of the Rhododendrons and figured it would be useful to compare the results.  

The photo you see at the top is shows both of them on top/bottom.  The plant on the top is the one that had Wilt-Pruf applied.  The plant on the bottom was left bare.  

The results?  Hard for me to say if it did anything, frankly.  I think the one that was treated has less spotting on the leaves, but maybe that's just random?  

Thus, I'd say the experiment is inconclusive in terms of preservation.  Certainly, it didn't harm the plants, so I'll stick to it this Fall/Winter, but I'm not sold on it doing anything significant in terms of preserving evergreens during the Winter.  One data point isn't enough, but maybe if I continue to treat just one of these things, it will become apparent over time?  With the high-profile nature of these two shrubs being right next to our stoop, I'm not going to take the chance.  I'll treat both this season and leave the experiment to a backyard conifer.