Hopefully I am in the right spot to ask this question. My burning bush was marketed as having amazing fall colour but it has been in the ground for two years now and is not burning. The neighbors' bushes all around me are totally on fire so I don't think the soil is a problem.
Most common reason for a burning bush's lack of burn is shade. Full sun is best, increasing shade results in decreasing colour. Another less common issue, is high nitrogen soil fertility, either from lawn fertilizer or direct fertilizing.
'neutral' soil is a description for soil with a pH of 7.0 (neither acidic nor alkaline), not an indicator of soil fertility (nitrogen, potassium, phosphorus, & trace elements). Soil pH isn't a critical factor Burning Bush anyway.
No....too much fertilizer can be a problem. Your lack of red on the burning bush is likely a shade issue as it is for the vast majority of burning bushes with little or no fall colour.
How, specifically do soil nutrients prevent red pigments in the leaves from appearing when the chlorophyll decomposes in fall?
