I’ve been planting petunias for over 30 years. For 10 of those years into large 6 foot long, 3 feet deep container boxes and the remaining 20 years into smaller container boxes 3 feet long and 8 in deep and directly into the ground.
What do I absolutely know? If I plant petunias in the smaller, shallow bottom containers, the petunias grow leggy rapidly. If I plant at end of May, by the end of July, they begin to look exhausted and I know by mid August, I’ll have to take them out. However, If I plant petunias in a deep container box or into the ground directly, they don’t grow leggy and last well through the summer and sometimes into early September.
So my #1 Tip for Planting Petunias? Go Deep.
Pat Coakley | The Photo Gardener
There is more flower deadheading in the leggy petunia boxes, too. In the ground produces the least amount of deadheading, the deep containers always have a need for deadheading but not as frequently as it is for a shallow container box. I have to do the shallow container box every day without fail.
