Plant Doctor Archive

Camellia leaves turning brown

The leaves on my container grown camellia are going brown. Six other camellias, however, are okay.

Has this camellia just been repotted or is it in need of repotting? Has it recently been fed or dried out for a period of time? Could it have been overwatered? Where is the camellia situated — full sun or shade? (Small leafed camellias are more tolerant of a sunny position than the large leaf varieties which prefer shade.) Without having additional information, it could be any number of things causing the leaves to go brown.

Firstly, I would check watering. Has the plant dried out recently? As the roots fill the container, water tends to run off rather than penetrate the root ball. Give the plant a good soaking at least twice a week, daily in hot, dry periods. Saturaid is a good additive to potting mix to help channel water to plant roots where it is required — your local garden centre or hardware store will have Saturaid.

Has the plant been fed recently? If an application of fertiliser is too high it can cause plant roots to burn; the leaves turn brown and shrivel up. A controlled release fertiliser is preferable for container grown camellias — try Osmocote, Green Jacket or Magamp. Regular liquid feeding throughout the season will also benefit container grown camellias. Nitrosol is ideal. Avoid using the blended Camellia, Azalea, Rhododendron fertiliser on container grown plants as it is too concentrated and will burn the roots. Little and often is the secret. Always follow the recommended rate stated on the packet. If you feel it is an overdose of fertiliser, leave the hose on the plant for at least an hour to flush out excess nutrients that may cause more damage. Repeat this several times.

If the plant has been in its container for a while, it could be in need of repotting. When a plant becomes root-bound it shows signs of stress by dropping its leaves — is this happening? You could repot your camellia now, but there will be little advantage. The best time would be after it has flowered in spring. If it is not looking like flowering in spring, repot your plant around July-August.

Are there any insect pests present like spider mites? You will notice a fine webbing on the back side of the leaf which will look speckled. Take the leaf into your local garden centre if you are unsure of what to look for. They will recommend a miticide such as Mavrik or Mite Killer.

As it could be any number of things affecting your plant, I hope this information is of some help to you.

Advice by Dr Dan Blanchon from Unitec's Diploma in Sustainable Horticulture and Bachelor of Resource Management.

Reproduced with permission from NZOOM Home and Garden content, from the previous website of  The views expressed here are not necessarily those of the RNZIH   HOME AND GARDEN   Plant Doctor Archives Main Page