Posted on 1st May 2012 @ 1:49 PM
Usually dropping leaves indicate a stress - there are several things that cause stress leaf dropping but the most common is water issues. Poor draining soils are often the culprit. We plant all of our camellias in a bark,sand,perlite mix which provides an excellent ratio of water-oxygen to the roots. In this type of soil, water drains from the pots and they can breath. When you use mixes with alot of peat moss - as in Miracle Grow Potting Mix and especially the ones that have added moisture retention components, it can spell trouble for Camellias that have been growing in a more porous mix. The water does not drain off, but stays in the soil and just like people who go under water - they can not breath, they drop leaves and eventually die. We can see this happening not only in poor draining soils, but when plants are planted too deeply. Camellias need moist, but not wet soil with organic or other material designed to provide slight moisture but that does not keep the plants wet. Roots need to breathe.
On our website, we list the best soil for container culture. Our potting mix is composed of 80% finely ground aged bark and perlite. This is what we recommend for container culture. We do not recommend using peat moss because it retains water and deprives plants of oxygen. We realize that not everyone can get these ingredients, so we have listed a substitute of Miracle Grow Orchid Mix (not potting or planting mix) and perlite. This is very close to what we use.
Common reasons for dropping leaves on Camellia:
Poor soil drainage from soils that do not drain well or hold too much water - results in plants being deprived of oxygen
Planting too deeply results in plants being deprived of oxygen and water
Chemical Damage - usually with browning of tips and margins then leaf drop
Cold Weather Damage
Normal spring leaf drop is usually indicated by yellowing of foliage then dropping but is replaced by new growth