planting purple wave petunias

Asked May 18, 2016, 2:51 PM EDT

Should I be cutting back the petunias as I plant them? They are good sized and have lots of flowers. I am using them for a border in my flower bed.

Ramsey County Minnesota

1 Response

In 1995, the Wave Purple petunia (Petunia x hybrida), a spreading petunia, was introduced. One of the best features of the Wave petunias are that they don’t require you to snip off the dead flowers to keep them blooming.

Below is an excerpt from The University of Minnesota Extension website on “Growing Petunias”. It has a lot of good information on choosing and taking care of petunias. The following is suggested:

“Wait until soil warms to about 60 degrees and frost danger has passed before transplanting petunias into the garden. Space grandifloras and multifloras about twelve inches apart in full sunlight, or several inches closer together when planted in a shadier location. Milliflora petunias can be spaced as close as four to six inches, but the spreading ground-cover types of petunias should be planted at least one and a half feet apart. Petunias must be planted much more closely together in containers in order to look attractively full right from the start.

Plan to provide some protection from midday sun for the first few days, if weather is hot or windy with few clouds at transplanting time. When grandifloras or multifloras grow about six inches tall, pinch them back to encourage rapid formation of flowering side shoots. Do not pinch millifloras or "spreading" petunias.

Whenever feasible, it's a good idea to remove faded flowers, including the portion below each flower where seeds will develop. This practice, called "deadheading," encourages blooming by preventing seed maturation. Although it may not be practical to deadhead masses of petunias in the garden, it's a must for flowering annuals in containers. Deadheading not only helps prolong blooming, it also keeps plants looking fresh, healthy and well-groomed.”

Here is a link to Cornell University’s website on “Petunia, Wave Hybrids” which will provide you with additional information.