By Dan Gill

LSU AgCenter Horticulturist

(10/06/17) The LSU AgCenter has named Supertunia Vista Bubblegum petunia (Petunia x hybrida Supertunia Vista Bubblegum) the Louisiana Super Plants selection for fall 2017. This is the first petunia cultivar named a Louisiana Super Plant, but it is well-deserved, given the outstanding performance of this petunia in trials and Louisiana landscapes.

In most parts of the country, petunias are considered a summer bedding plant — planted in spring as the weather warms and blooming through summer. Here, however, petunias are not a particularly great choice for summer flower beds.

The main issue is the intense heat of summers in the Gulf Coast region where we live. Petunias are not at all happy when temperatures reach the 90s. They will lose vigor and tend to languish here during mid-to-late summer. Plant breeders have tried to deal with this by developing petunia cultivars that are especially vigorous and more heat-tolerant. The Wave petunias were among the first of the heat-tolerant petunias, and the Supertunia petunias are another group of vigorous, heat-tolerant petunias.

But even the heat-tolerant cultivars have a hard time making it through our long, hot summers. They typically play out in July, leaving gaps in our flower gardens at a time when it is too late to plant additional warm season bedding plants and too early to plant cool-season bedding plants. For these reasons, petunias are best grown as cool-season bedding plants here to brighten our landscapes from October to May or early June. The planting season runs from October to early March.

That said, petunias are among the more heat-tolerant cool-season bedding plants. This allows us to plant them now while temperatures are still reaching the 80s during the day. Most cool-season bedding plants should not be planted until daytime highs are reliably staying mostly in the 70s. That makes now through fall a great time to plant petunias.

What about winter freezes? Petunias are hardy down to around 20 degrees, and that allows them to easily survive typical winters in south Louisiana. If temperatures in the low 20s are predicted, move petunias in containers to a protected location or indoors and throw covers over any petunias that are newly planted. If temperatures in the teens are predicted, throw covers over all petunia plantings. North Louisiana gardeners may want to wait until late February or March to plant them.

Supertunia Vista Bubblegum

Supertunia Vista Bubblegum has been one of the best petunias in landscape trials at the LSU AgCenter Hammond Research Station for a number of years. Its consistent superior performance has proven that Supertunia Vista Bubblegum is one of Louisiana’s most durable petunia cultivars. And it’s not just at the Hammond Research Station. Supertunia Vista Bubblegum has been an excellent performer in university trials across the country, and it has been one of the most talked-about petunias in the horticulture industry during the past few years.

The flower color is a bright, medium pink with darker pink veins. This color shows up beautifully in landscape plantings and combines with a wide variety of other colors. The flowers are not overly large and hold up well in rainy weather. The plants literally cover themselves with flowers when in full bloom, and the plants stay neat looking without deadheading.

Petunias bloom best in full sun but can tolerate a limited amount of shade, especially in the afternoon. Beds should be well prepared and enriched with several inches of compost worked into the upper 8 inches of the soil. Raised beds work best at providing the good drainage these plants prefer.

Supertunia Vista Bubblegum is a vigorous petunia with a 3-foot spread at maturity. It can grow to about 16-24 inches tall. When mass-planted in the landscape bed, it is best to plant the petunias on 18-inch centers — 18 inches from the middle of one plant to the middle of the next plant. This wide spacing means fewer plants are needed to plant a bed.

Supertunia Vista Bubblegum plants are generally sold in 6-inch pots. Carefully remove the plant from the pot and plant it with the top of the root ball level with or slightly above the soil in the bed. Apply a controlled-release fertilizer at planting, following package directions. For the best growth and flower production, fertilize these plants twice a month using water-soluble fertilizers applied with a watering can or hose-end sprayer.

After planting, apply mulch a couple of inches thick to improve the appearance of the landscape bed and help with weed control.

This petunia works equally well in containers and hanging baskets where the flowering branches and shoots will cascade over the edge. Plant them alone in a container or combine these petunias with other cool-season bedding plants.

Watering plants in beds will rarely be needed during the coldest months (we get plenty of rain), but water them regularly as needed once the weather begins to warm in spring. Early morning watering is best for petunias and other bedding plants. Plants growing in containers will need more attention to watering, especially later in the season when the plants are larger, roots have filled the containers and the weather is warmer.

We all look for the best, toughest and most reliable bedding plants for our flower gardens. Give the Supertunia Vista Bubblegum petunia a try. I think you will agree that it is one of the most reliable and outstanding cool-season bedding plants for our landscapes.

Supertunia Vista Bubblegum grows in the trial gardens at the LSU AgCenter Hammond Research Station. Photo by Allen Owings