My garden is not heavily planted with flowering annuals. I focus more on trees, shrubs, and herbaceous perennials. However, I can’t resist adding color to my containers and filling blank spots in my perennial border with annuals. So if I’m going to plant an annual, it needs to perform. I look for something that flowers nearly nonstop and isn’t overly fussy. It’s hard to deny hybrid petunias (Petunia cvs., annual) check all the boxes. They are tough, drought-tolerant, blooming machines. If you’re going to plant one annual, petunias are a good choice.

But which petunia is best? Many universities across the Southeast, including the University of Georgia, North Carolina State University, and the University of Tennessee, trial all kinds of annual plants, including petunias. Well, the data is in, and I wanted to share combined results from these universities in our region. All the petunias that came out on top of the trial results have been developed by or marketed by specific companies in the industry. These findings have not been influenced by any of those companies. I am simply sharing the results from independent tests done by universities. You may not have heard of some of these company names. They are often the suppliers to retail growers.

Best of the best Supertunia^® varieties from Proven Winners

Known to be self-cleaning and very floriferous, the Supertunia^® series of petunias from the Proven Winners plant brand have a lot of good choices. Proven Winners lists these petunias in three different ways. First, the regular Supertunia^® are shorter and are great for landscape beds or spilling out of a container. The petunias listed in the Vista^® series are taller, vigorous, and have a cloudlike mounding habit. Petunias listed as Mini Vista^® are distinctly smaller; while still mounding, they also spill and cascade. They thrive at the edge of beds or in containers and have smaller-size flowers. There are dozens of different petunia cultivars in this series. If I had to pick one from the series, it would be Supertunia Vista^® Bubblegum^® petunia (Petunia ‘USTUNI6001’). This has been a winner year over year in trials and in my garden. For me, it is just the right shade of pink that pairs perfectly with other annuals. I additionally wanted to share other top regional picks for you from the series:

• Supertunia^® Sharon petunia (Petunia ‘BBTUN22503’) has fuchsia-and-white petals with a tie-dye effect.
• Supertunia Mini Vista^® Violet Star petunia (Petunia ‘USTUNJ1901’) has dark purple and white-striped flowers.
• Supertunia Mini Vista^® Pink Star petunia (Petunia ‘USTUNJ2401’) has the same striped flowers but with light pink and white.

The Durabloom^® series from Dümmen Orange has one of the best purple petunias

Dümmen Orange has a crazy number of petunia offerings for the public. They have pushed the envelope when it comes to new color combinations. However, in trials in the Southeast, Durabloom^® Electric Lilac petunia has been a top performer. This plant comes from a series of petunias that are interspecific hybrids. With this plant, you get bright, vivid purple flowers, a nice branching structure with a spreading habit, and good overall durability.

Petunias from Ball Horticultural’s family of companies turn heads

The original Wave^® Purple Classic spreading petunia (Petunia ‘PAS3186’), which debuted in 1995, was a true gardening breakthrough. Strangely enough, this petunia was discovered by a Japanese beer company. The Wave^® brand is one that gardeners have known for years. Innovation in petunias continues through Ball Horticultural’s various plant-breeding companies. One of the top petunias on the list from recent trials is Tidal Wave^® Silver petunia (Petunia ‘PAS97287’). I singled this petunia out from other top trial performers because of its unique white-pink-silver color and overall vigor. Additionally, this petunia was honored as an All-America Selections Winner for outstanding performance and long-lasting color. Many of the varieties in Ball FloraPlant’s ColorRush™ series of petunias also did very well in trials. Below is an additional list of petunias that performed well in the Southeast from various Ball’s Horticultural companies.

• ColorRush™ Red petunia (Petunia ‘Balcushed’) has vivid dark red flowers.
• ColorRush™ Pink petunia (Petunia ‘Balcushink’) has medium pink flowers.
• Wave^® Carmine Velour petunia (Petunia ‘PAS1302763’) is similar to ColorRush™ Red with dark red flowers, but these ones have a magenta tinge.
• Tidal Wave^® Red Velour petunia (Petunia ‘PAS91421’) has the darkest red flowers of all.

Suntory Flowers has one of the best two-tone petunias

Suntory is a large, diverse company. Its Surfinia^® selection of petunias predates Wave^® petunias and was marketed in Europe in the very early 1990s. Coincidentally, much like the Wave^® petunias, this was spearheaded by a Japanese company that focuses on alcohol production. There are many petunias now in this series. One of the top performers in recent trials has been Surfinia^® Purple Heart petunia. This is a magenta-and-white pinwheel-flowered petunia that has done well in the Southeast, particularly in containers. This is an extremely fast-growing petunia with a dense, profuse bloom.

How to care for petunias

Petunias are tough plants—so tough, in fact, that I have seen plants rebound even after containers have been left to go bone dry. However, there are a few things to know. Petunias like full sun, they don’t like to be overwatered, and you can’t be afraid to cut them back. Try to avoid planting petunias in the same spot every year to avoid disease. Water petunias only when the soil has started to dry out. When watering, I try to avoid getting foliage and flowers wet. This is accomplished by putting a watering wand under the foliage at low pressure. In the middle of the growing season, give petunias a haircut. I often reduce plants by half. This keeps plants looking their best later in the season. I suggest using the liquid fertilizer of your choice on petunias about once a month to keep them growing strong (more often in containers). Picking a good petunia variety that is a proven performer in the Southeast is important. The list provided here is a good one. However, don’t be afraid to go off script and try a new variety that catches your eye.

For more on top-performing annuals, check out:

• Must-Have Annuals
• Best New Plants: Annuals
• Let’s Argue About Plants: Annuals Worth Your Money

And for more Southeast regional reports, click here.

—Andy Pulte is a faculty member in the plant sciences department at the University of Tennessee.