My azaleas seem to have developed what appears to be a small white fungus on the tips of their branches. It first appeared on a white azalea (which didn’t bloom this year,)and has quickly spread to pink azaleas after blooming profusely this year. The pink azaleas are about 15 years old and have bloomed happily in shady areas of our condo gardens
The azaleas are not near each other and I have not touched them in any way.
Could this be due to our recent rain in North Vancouver ?
Thank you for contacting Toronto Master Gardeners about the white fungus on branch tips of your Azaleas. There are various problems that might cause azaleas to fail. Your photograph is out of focus and it’s difficult to see the actual white fungus. Below are common azalea problems:
1. Root and Crown Rot
Your West Coast location is ideal for azaleas. With adequate moisture and mostly acidic soil, azaleas should do well. These plants enjoy consistent moisture and do not benefit from periods of drought. Excess moisture with insufficient soil drainage invites the fungus (Phytophthora) species, causing root and crown rot. Leaves droop and curl inward and the root system is soggy and black. Selecting disease resistant species can help with this problem. In the link below, there is a list of resistant plants. Although you mentioned recent rain, your description doesn’t match these symptoms.
Azalea and Rhododendron diseases
2. Petal Blight
If the flower petals have tiny spots then the fungal disease (Ovulinia azaleae) may be present. The spots are white on coloured petals, and brown on white petals. The spots become larger, petals rot and it is spread by wind, rain and insects. This fungus is present in the soil and survives through all seasons. Solutions are removing infected petals, removing litter at base and water at the base of plant, not overhead. The link above details chemicals that may help with this fungus. Given your description of fungus on branch tips, this is probably not the problem.
3. Leaf Gall
Another common fungal disease is Leaf gall (Exobasidium vaccinii) which attacks in April and May. Leaves, buds and even stems become distorted and turn white in the later stages. White galls are covered with a white powder layer. Eventually the galls turn brown. Below is a photo of the gall distorting azalea growth. Unfortunately it is not evident in your photo if there are galls present on the branch tips. However the white powdery covering may indicate Leaf Gall.
Fortunately this problem does not destroy the plant. Removing the galls and destroying them is the first step. Research acceptable fungicidal sprays in your region and if it continues, chemical invention may also help.
Azaleas produce exquisite, joyous blooms and hopefully you can address the problem and they will continue to enhance your condo gardens.
Perhaps you can reach out to the BC Master gardeners for further help https://www.mgabc.org/