Question: I’m sending a photo of my ceanothus. It was planted two years ago, and this year the flower heads are mostly dead looking. I think this is called bud blast. Can you recommend a spray?
Answer: When flowers dry out like this, the reason is often to do with growing conditions. Thsi year, it could even be late frosts causing the failed flowers. Alternatively, if the roots have been disturbed or dried out, flowers or buds are often sacrificed in a damage-limitation attempt. Excessive dryness at a critical point may be to blame. It is rhododendrons that can suffer from a disease known as bud blast, which is transmitted by rhododendron leaf hopper; it is only this genus that is affected. If your ceanothus has flowered in the first couple of years, it’s likely that all will be well next year as long as there are no late frosts.
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