I started a tea plant (Camellia sinensis) from seed during the late fall. The plant is in a partly shaded, sun dappled location.
Over the last few months the new leaves have been getting lighter in colour. Thinking the problem might be related to insufficient soil acidity, I added a pH reducer about 1 month ago, however I see no change.
What do you think is causing the problem and what remedy do you recommend? Thanks.
Thanks for your question. It is an unusual plant especially starting from seed. Good for you for getting it going.
To me it looks like your leaf has a fungus, likely as a result of overwatering. I would remove the infected leaf and carefully scrape off about 2cm of soil adding back fresh clean soil of the type used in the original planting. You may want to spray it with an organic type fungaside found at a reputable nursery. As you still have a baby plant use lightly. In the future water only when the soil feels dry. Saturate the root ball and let dry out again- not bone dry but dry to the finger on the top of the soil. Don’t leave standing water in the saucer.
If it appears to recover (leaves are all the same colour and no brown spots), I would move it to receive full sun if possible.
Above-ground symptoms of wet root rot diseases (Phytophthora and Pythium spp.) are poor plant growth, thinning of the foliage, and yellowing of the leaves, with the oldest foliage being affected first. This disease is triggered by periods of excessive soil moisture. Provide plants with adequate drainage and reduce irrigation.