Hi Mike, I see you are using Don's technique of using an umbrella to reduce the glare. I think you might need an assistant to angle the umbrella so that the whole plant is shaded. Almost impossible to do if you are by yourself. Regards Betty
Now you have given me a clue to technique, but it was actually just a tree giving the shadow. I was doing a Waterwatch so had enough to carry anyway. Spotting this plant encouraged me to go looking for more and I was rewarded with a patch of around 1000.