Question
Is there a way to keep petunias from getting leggy?  Seems to happen even when pinching off.  Have tried to cut off main stem & it just stops growing???
Thanks
John

Answer
John,
You've undoubtedly noticed that petunias only produce flowers at the ends of their stems. The traditional varieties, the ones you usually buy in six packs, need to be deadheaded (pinched) by clipping the stem underneath where the flowers were - this removes the developing seeds so that the plant keeps blooming. It continues to bloom, however, at the end of the stems.

Wave and Superpetunias don't need to be deadheaded, but they also bloom at the end of the stems. So the key to keeping a petunia flower filled and less "stemmy" is to shorten the stems by at least a half, beginning early in the summer. If, starting in June, you cut three or four stems either in half or back so that you only leave 3 to 5 inches, the plants will branch out and make new stems starting where the cut was made. So you can see that if every week you're shortening three or four of them, you'll be constantly creating new shorter stems that will be closer to the center of the plant, and blooming at the ends.

This is particularly hard for people when the plant is full and looking great, as so many petunia hanging baskets are when they are soil in May. But if it's not done, the plants end up with lots of stem and a few flowers at the ends.

In addition to this constant partial pruning, fertilization is important - either give them some time-release fertilizer early in May and late-July, or a combination of time-release and organic fertilizer when planting, or periodic liquid feeds throughout the summer.  Always water the plant well first - never fertilize a thirsty plant!

With your plant now, you can either take the "tough love" approach and cut the entire thing back, and fertilize, and wait two or three weeks for new growth, or cut a third of the stems back this week, another third in two weeks and the final third in another two weeks.   Perhaps the quickest way to a nice looking plant is to cut the entire thing back and clip off a bunch of 6" pieces off the ends of the stems and root them. They should root in new soil, using rooting hormone, left in the shade in a couple of weeks and can then be pinched and planted into your containers or garden.

I hope this helps,
C.L.