I have two different types of butterfly bushes. This summer would be their 3rd year in my garden and they were 2 year old plants when I put them in. Last spring I pruned them according to what I had read...that is about 2 ft from the ground. They grew to over 8 ft. tall and bloomed till frost. This spring I did the same pruning and I have not a single leaf or leaf bud. In fact the branches appear to have died. I have some volunteers coming up about 3-4 ft from the original plants but I don't understand what has happened to the main ones. I have good soil, full sun and plenty of water. Can you tell me what possibly could have happened. We had a harsh winter but all my other perennials have come back splendidly.
It sounds as though your butterfly bushes have suffered from the cold winter temperatures, but since there is growth, they are coming back from the roots. For butterfly bushes, try pruning in spring, after the new growth emerges. Many people cut their butterfly bush back in autumn, as part of their fall clean up. But particularly in cold climates, this can leave your butterfly bush more susceptible to damage over winter. Do not prune until you see green buds on the stems. Make your cuts just above where big, healthy leaf buds have formed. It can take several weeks. But do prune your butterfly bush. Left unpruned, large butterfly bushes can become “second story” plants: their flowers form way up at the top so you can’t enjoy them unless you have a second story window. The warmer your climate, the more you should cut back your butterfly bush each spring. Also, be patient. Butterfly bushes tend to be one of the later plants to leaf out in spring. Even if everything else in your landscape is turning green, that doesn’t mean you’ve lost your butterfly bush. Many people recommend waiting til as late as Father’s Day (the third Sunday in June) to be certain their butterfly bush perished. It can be very surprising to see how quickly a butterfly bush can recover, even if it takes that long to come back!
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