My burning bushes are planted in full sun. I understand they need to be in full sun in order to have lots of color. The first 4 or 5 years mine were planted, they showed no color but green. I had decided maybe I did not have a "burning bush". But, last year, the color was spectacular! This year, so far, the bush is not as colorful but trees are just starting to change color here. So, we'll see. I do not think soil ph has anything to do with how colorful they get...just how much sun they get. Could be wrong though.

It is my understanding that Burning Bushes need at least 6 hours of sunlight a day in order to get the amazing 'burning' effect in the fall. Less than that and they will fail to produce the red shades they are known for. I don't know if this means morning sun or afternoon sun. I am planning to put three in my front yard this spring. They will get morning sun with a bit of evening sun. Fingers crossed that they will "burn" in the fall!!
As far as changing the ph...I don't think that will help.

Yep, the Burning Bush definitely needs full sun or as close to it as possible! I have several along my driveway, and they were shaded most of the day for the first couple years I lived here. Then, after removing some brush and trees from a hill across from them, and letting the sun through for once, they turned a beautiful, bright read this past Autumn!

I have noticed mine are a brighter red in drought years. Maybe if you held off watering late in the summer you could trigger better fall color? Most of our trees react this way also--thirst produces brilliant fall foliage.
I do end up watering in the winter, though. Don't want to kill them!
Cindi

I sort of agree with Cindi - you don't want to underwater them, but my burning bush sometimes needs help realizing that it's fall! Some years if I water too much too late, it'll stay quite green up until it starts to freeze and then all of a sudden, the color starts to change; at that point, it is too late to get anything too spectacular. If you slow down on watering in later summer, it clues your burning bush into "it's fall..time to turn color". Cool nights helps as well.

But your number 1 problem is the shade!