Camellia trees are grown for their showy blooms, which range in colour from white to pink to red. Unlike most blooming shrubs, camellias are planted in full or partial shade to prevent the leaves from scalding in the sun and turning yellow. It does particularly well under the canopy of another tree, where it receives filtered sunlight. After three to five years, camellia seedlings begin blooming. If your camellias have a poor flowering display, there are several possible causes.
Pruning of camellia branches should occur after they are done flowering each year but before new buds appear. This is so the flower buds aren't accidentally removed. Camellias only require light pruning, and overly drastic pruning can cause fewer blooms the following season. However, removing excess flower buds prior to blooming, referred to as debudding, can increase the size of the blooms.
Camellia blooms are more susceptible to cold temperatures than the plant itself. If temperatures fall below -6.67 degrees C, the size of blooms may be reduced. A sudden decrease in the temperature can also damage open blooms and cause them to drop. Conversely, unexpectedly hot weather in the spring or fall can also cause camellias to drop its flower buds.
Camellias achieve optimal blooming with uniform moisture. To help retain moisture and keep the soil cool, spread 2 to 4 inches of mulch or pine straw around the base of the tree.
Poor Soil or Drainage
Camellias grow and bloom best in slightly acidic soil with a pH of 6.0 to 6.5. Compact or clay soil should be aerated or amended with organic matter and sand to improve drainage and get your camellia trees flowering again.
Fertilise after blooms disappear with organic cottonseed meal or a commercial fertiliser specially formulated for acid-loving shrubs. However, adding too much nitrogen can overstimulate leaf production and reduce blooming. If camellias are located too close to trees with shallow root systems, they will not receive the water and nutrients they need.