Expert: C.L. Fornari - 5/26/2004

Question
I live in North Carolina.  Currently I have two petunia plants in hanging baskets.  One is a purple wave petunia, and the other is a purple trailing petunia.  I was wondering if all I had to do to keep them blooming is to deadhead?  Do I just pull the dead flowers off, or should I pinch back the sprouts to encourage growth.  My purple trailing petunia came with very little information, and the purple wave petunia came with even less.  I would appreciate your help.  

Thank you,

Jessica

Answer
Jessica,
If you look at both petunias you'll notice that the flowers form on the ends of the shoots.  This means that if you encourage more shoots, you have more flowers, and the way to produce more shoots is to pinch the ends off the stems that you have.  That's step one to keeping your petunias blooming.

Step two is to regularly fertilize using a fertilizer that is a 20-20-20 or equivelent.  (10-10-10) etc.  So called "blossom booster" fertilizers are NOT as good - these annuals bloom better with higher nitrogen levels.

Step three is to dead head your trailing petunia regularly by cutting off the spent flowers BELOW the flower, being sure to cut off the swollen place just below the flower.  This is the area seeds are developing in, and it's the seeds you want to be sure to remove.  The wave does not need to be deadheaded.

Step four  is to cut back a few of your stems every two or three weeks.... cut four or five stems back by half every other week to keep plant bushy and flowers all over the plant instead of just on the ends.  

Step five is to water deeply when dry.  If these are in baskets this might be twice a day in hot weather.... don't keep them wet, but don't let them wilt either.  You'll develop the "eye" to tell if it's thirsty, and you can lift the pot to see if it's getting light (dry) and will soon need water.   NEVER FERTILIZE A THIRSTY PLANT.  Water first and then fertilize a couple of hours later, or use time release fertilizer.

I hope this helps!
C.L. Fornari
www.gardenlady.com