Over the past month the leaves on my Mexican Orange have begun turning yellow. A few leaves are all yellow, others about 1/3 yellow. It is in a very large pot in mostly sunny location and is not lacking for water. Have had it for 2 years. It hasn't exactly thrived but it's never looked this bad. Any ideas? I live in Victoria BC.
Discoloration and die-back frequent with this shrub in this region. I figure much of the time the soil is too cold and wet.