Documents: Latest From: The Real Dirt:

Demystifying Spreading Petunias
by John Harmon
December 8, 2002

Last week I talked about a couple of the new petunias offered this year and a number of people have contacted me about spreading petunias. There are so many "new" petunias being offered it's confusing even to those of us that are growing them every year. Most folks wanted to know what the difference was between all these new types of spreading petunias. Choosing the right one for your planned use will give you better plants. Each series will produce slightly different types of plants. Here's some information on the different types and their habits.

The first introduction was the "Purple Wave" available since 1995. This one will grow between four and six inches high and spread out to 48 inches. It will continue to bloom throughout the summer right up until the frost kills it. I stuck some of these out in an old tractor tire planter in the middle of the yard and couldn't believe how far they spread out from the tire. They look great in hanging baskets and if planted on a south-facing slope will work like a ground cover. The Wave series comes in blue, lavender, misty lilac, pink improved and rose as well as the purple. Most breeders are still trying to come up with a true red wave.

The 2002 introduction in the "Wave" series was the "Tidal Wave Silver". This one has a slightly different growth habit. If you space these plants close together they grow tall, up to three feet! If they are spaced over a foot apart they will grow lower and spaced two feet apart can spread up to five feet or more! This plant will spread the most of all the spreading petunias and get the tallest.

Another series of spreading petunias is called "Avalanche". These are slightly different than the "Wave" series. It will grow up to eight inches tall with a spread of about two feet. When I grew this one a couple of years ago I found them to be slower to fill out and lower than the "Wave" series. I think they are more sensitive to our long hours of daylight in the summer. They come in red, cherry, salmon, and the new color for this year is white. This series was the first to produce the color red even though it was a very dark red.

The "Ramblin" is another series of spreading petunia introduced a few years back. The have about the same habit as the "Avalanche" except they spread a little more. I haven't tried this series in the Yukon but they should work. This series claim to fame is that they produced the first dark blue color. Now there are other spreading petunias that have a blue like the "Wave" series.

There's another semi-spreading petunia called Kahuna. It's an F1 hybrid. This series is more upright so it can be grown in smaller pots at higher densities. It also claims that the plant will "trail" like a trailing petunia. It flowers two weeks earlier than Waves. It grows up to 18 inches tall with purple flowers covering the entire plant. It easily spreads to four feet across. This one had the highest score of any trailing petunia (4.7 of possible 5) at the Penn State trials. It comes in white as well as the deep purple.

The "Trailblazer" comes in just one color, violet. It may be a good one for the north because it's less sensitive to day length. It's the petunia used as a winter annual in temperate climates. It flowers two weeks earlier than the "Wave's" and it will start to flower when still quite small in pots. It will produce flowers over the entire plant and spread to four feet across and eight to ten inches high.

The petunia called "Crazy" has a spreading habit as well as trailing. It's good for slopes and rock walls. The breeder claims "This spreading Petunia will create blankets of color as it creeps and crawls amongst rockeries, spills out over hanging baskets, or envelops embankments". The flowers are long lasting and come in pink, purple, blue and coral.

No matter which series you choose there are a couple of things you can do to maximize the growth of spreading petunias. First of all don't let them dry out. They should be watered regularly without keeping them wet. They also need to be fed. Apply a liquid fertilizer once a week or use a combination of liquid and slow-release fertilizers following the rates recommended on the label. The other consideration is where you plant them. All of the spreading types of petunias need full sun. A minimum of six hours a day is required for most of them. Of course the more sun they get the better they will bloom but the down side is that they will also dry out faster.

All of the spreading types of petunias have one thing in common, they are pricey. The seeds or the plants are more than you will pay for other kinds of petunias. Expect to pay between a quarter and a half a buck each for seeds! Take good look at where you will be planting these flowers and choose the series that best suits the location. The good news is that there's a series to suit every need. Seeds are available from most of the seed companies. For more information on "Wave" petunias check out

John Harmon owns and operates Tropicals North. Write to John at The Real Dirt, c\o 211 Wood St., Whitehorse, YT., Y1A 2E4 or e-mail

  • New Eden
  • Kids Garden
  • Plant a Row Grow a Row