By SF Gate Contributor Updated May 13, 2021
When the leaves of your camellia fade and fall off, it could be just normal regeneration of the plant. But if the problem persists, it’s most likely something more serious. Whether you’re growing shade-loving camellia (Camellia japonica) or the more sun-tolerant camellia species (Camellia sasanqua), both of which grow as perennials in U.S. Department of Agriculture plant hardiness zones 7 through 9, adjusting your cultural practices may be all you need to have your camellias thriving again.
Watch Sun Exposure
Move a camellia from a shady location to where it receives direct sunlight and sunscald results because the plant is not adequately hydrated. Signs of sunscald are bronzed, dried out leaves in areas where sun is directly contacting foliage. Prevent sunscald in Camellia japonica by growing it in partial- to full-shade. Camellia sasanqua tolerates more sun, but in the heat of summer can suffer from sunscald.
Correct sunscald by moving shade-loving varieties to a shaded area and ensure sun-tolerant varieties are adequately hydrated. Prune faded, dry leaves. Avoid spreading disease among your shrubs by sterilizing pruning shears before use. Soak them for at least five minutes in a solution made of 1 part rubbing alcohol and 1 part water, and let them air-dry. Sterilize again before moving to another shrub and when finished pruning.
Water the Plant Properly
If leaves on your camellia begin to fade, wilt and drop from the plant, you could be dealing with phytophthora root rot, says Clemson Cooperative Extension. Phytophthora fungal pathogens can contaminate garden soil and potting mixes. When soil becomes waterlogged, spores attack camellia roots, causing them to decay so the plant can’t take up nutrients.
Determine if the shrub has root rot, and not a nutrient deficiency, by digging up roots and examining them. Look for soft roots that break easily and have brown interiors. Prevent phytophthora by allowing soil to dry out between waterings, advises UC IPM Online. Camellia infected with phytophthora should be destroyed and the soil replaced. Camellia japonica is especially susceptible to phytophthora root rot.
Don't Over Fertilize
Lack of nitrogen will cause camellia leaves to fade, but too much fertilizer will make leaves appear burnt and dried out. Browning occurs just around leaf edges or covers the entire leaf in extreme cases. Over fertilization harms roots of camellia so they cannot take up nutrients.
Prevent over fertilizing by applying a fertilizer for camellias in the spring after the shrub has bloomed, then again in May and July. Apply 1 tablespoon for each foot of plant height. Do not fertilize when the shrub is not growing. Apply slow-release fertilizer twice per growing season, in March and July, in the same manner.
Protect From Wind
If your camellia dropping leaves is in an area where it receives direct wind, leaves can suffer wind scorch. Leaf edges dry out and become brown first, then as symptoms worsen entire leaves fade and become dry. Wind scorch isn’t the result of wind burning the leaves, but rather the combination of wind drying out leaves and soil, and the plant not being able to take up enough water to replenish lost moisture.
Prevent wind scorch by mulching around camellia shrubs so soil retains moisture; plant camellias in areas where they are protected from strong wind; and move potted plants into protected areas. Prune scorched leaves in spring to allow for new growth.