What Is Wrong With This Banana Shrub?

Question

I have 2 of these shrubs. One is in full sun and the other, which is more of a tree form and more open, is under a well trimmed up Oak tree. Plenty of room for air circulation. Both have the same issue on the leaves. Pics attached of leaf.

• 
• 
• 

Answer 1

This looks to be the early signs of Algal Leaf Spot, or possibly coupled with a bacterial infection.

Most bactericides and fungicides will take care of the issue:

https://www.gardeningknowhow.com/garden-how-to/info/using-fungicides-in-garden.htm

https://www.gardeningknowhow.com/special/organic/biofungicide-information.htm

https://www.gardeningknowhow.com/garden-how-to/info/homemade-fungicide.htm

https://www.gardeningknowhow.com/garden-how-to/info/applying-bactericide-to-plants.htm