At the moment, out of the 9 petunia varieties that I planted new from seed in this Spring, only 3 still have any flowers in bloom. Plus, those remaining flowers are extremely sparse. This variety is "Bees Knees", and the above flower is the very last flower I can currently find on it.
I've read that when Petunias "bloom themselves out" (as mine have), it helps to severe prune the plants back to encourage new growth. Although I've never done it before, I did that today. If a killing freeze doesn't happen first (and the pruning actually works), I will winter all the plants over in my Solar Room. Last Winter, I wintered 3 petunias over indoors, and those bloomed all well for me all this Summer.
One of my Petunias (normally an annual) dates the whole way back to 2018. Although that one finally stopped flowering when tempts hit over 100° last week, the plant still looks in very good shape. So, I'll again try to Winter it https://pbase.com/britestar/image/170861843 ("Holy Cow") over again, too. It flowered indoors for me last Winter. Hope I have as good of luck this Winter with the others currently on my 2022 deck.
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