Why is my rhododendron flowering now – and why is the bud pink but the flower white?
The photograph shows a rhododendron in Hartungviken, Sweden, opening a single flower in September. It looks unusual, but the colour change has a simple explanation. The most useful advice now is about what to leave alone.
This is a rhododendron that has started opening a flower bud unusually late in the season. Occasional autumn flowers can follow changes in the weather or a long mild spell, and are usually nothing to worry about in themselves.
It is normal for the bud to look pink and the open flower to be white. The pink you can see on the outside comes from the protective bud scales and the outer surface of the bud, while the petals inside are white. Many rhododendrons show more colour in bud than when fully open.
What to do now
Leave the flower in place and avoid hard pruning in September. The shrub will soon be going dormant, particularly in your part of Västernorrland in Sweden, and pruning or feeding now can disrupt its preparation for winter. Simply keep the soil lightly and evenly moist during dry weather, then remove the faded flower later without damaging the buds beside it.
The small drawback of autumn flowering is that this particular bud will not flower again in spring. If only one or two buds are involved, it rarely makes much difference. Check whether the rest of the shrub flowers normally next spring; if it does, no action is needed.
Sources and images 1
- Original reader contribution ↗Reader question