Marianne's Response

My Petunias Grow Too Tall

I raise my petunias from seed in a greenhouse, and once ready to be transplanted, I plant them in containers.
My question is: The seeds I buy say they will be between 6 and 12 inches tall. Mine always grow up to 3 feet, at which time they begin to look awful, spindly, etc. I see petunias in the gardens where I live, and they are generally no more than 8 inches tall. Same seeds. What am I doing wrong? They always turn out spindly. This year, I have cut back the spindly vines after they have bloomed. The vines come back spindly again. Help

Posted by Rick Robinson on August 28, 2021

Marianne's Response

Two tips for growing more compact petunias. First, give the seedlings more light and bottom heat. Second, when the seedlings are six inches tall, pinch them back to about half their height so that the young plants branch outward rather than upward. You can also buy seeds of more compact varieties rather than the spreading groundcover style of petunias. Keep growing, Marianne Binetti

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