Hi: I have a black bamboo tree which is approx 2 years old. This summer it is loosing it's leaves. Each day there are many brown leaves on the ground. It is irrigated by our irrigation system which comes on every evening for 8 mins. Does anyone know what might be causing this?
Have you checked the soil to see how moist it is? 8 minutes isn't very much time to get water into the soil. If you dig around the bamboo and see that the soil is dry then and you'll need to make adjustments to the automatic irrigation system.
Agree with the above. Give it a real good soak manually with a hose. Give it some water soluable fertilizer as well to save it. Spray the foliage as well.