I'm asking for a friend who is puzzled. She purchased this dahlia five years ago. The first four year all the tips of the petels were uniformly white as she expected. She divided the tubers at the end of season last year. This year they have been coming up with random white tips.
Any thoughts on why this happened? Is it a type of reversion? Or perhaps something caused by the division?
Someone suggested it might be caused by something in the soil she added last year.
It's just a blip in the genetic code and is not particularly unusual, especially in colour break flowers. These often occur naturally, and are selected for breeding to try to maintain whatever form of colour break has occurred, but, over time, especially in dahlia as the tubers increase, the DNA may alter again and the colour break pattern becomes more random. It's nothing to do with the soil, and there's nothing to be done about it I'm afraid. Your friend may find, eventually, that one section of the tubers she has split does produce the original type of flower - if that happens, then isolating the particular tuber its coming from, separating it and growing it on separately might give a plant ongoing that is not so random.
Gosh, this is normal. Especially with these hybrids. I would not worry about this at all. Yes, it is reversing to previous DNA a bit? But probably won't ever stop having white tips.
What exactly do you mean that she changed her soil last year? PH change could be a factor. Are these Dahlias in the garden or are they in pots? Does she dig up and bring the bulbs in each winter? Does she have to because she's in a zone with real winters? What does she do for fertilizer?
