If onions, bell pepper and celery are the “holy trinity” of New Orleans cuisine, then jasmine, magnolias and gardenias are their rivals when it comes to spring gardens in the Crescent City. The air in April and May is filled with their fragrance.

Gardenias (Gardenia jasminoides) are scenting our city gardens and neighborhoods right now, at a time when the blooms of Confederate jasmine have peaked and magnolias have yet to fully hit their stride. It seems that everywhere you look, there is a gardenia bush (or two) blooming riotously.

According to Tom Wolfe, owner of Urban Roots on Tchoupitoulas, several varieties of gardenias appear regularly in local landscapes.

“If you have room for it, nothing beats August Beauty,” he said. “But it can grow 6 or 8 feet tall if not controlled. It has beautiful dark green glossy leaves and the blooms are the double petaled ‘rose’ type that people most often picture when they think of gardenias.” Mystery is a second favorite, often found in local gardens that can grow quite large.

Like all gardenias, August Beauty and Mystery prefer a slightly acidic soil to thrive. Local soils, however, tend to have a higher pH and therefore are more alkaline than gardenias naturally want.

“That’s why you’ll see leaves yellowing, especially when the plant is in bloom. Its survival instincts tell it to sacrifice the leaves for the bloom, because that’s how it reproduces,” Wolfe said. “But if you add organic matter in the form of compost, coffee grinds, leaves or any decaying organic matter to the soil, they’ll create enough of an acidic environment that the plants will be able to absorb nutrients better and more quickly.”

For gardeners who don’t have room for a gardenia behemoth such as August Beauty or Mystery at home, Wolfe likes to recommend Frostproof to clients at his nursery.

“The LSU AgCenter made Frostproof a SuperPlant a few years ago because it is a lot more compact than August Beauty, meaning it can fit in better in home gardens, and because it’s a little more adaptable,” he said. “It’s what I would recommend to anyone who hasn’t grown a gardenia before because they are likely to have success and develop a little confidence.”

A third variety, Aimee, has many of the same qualities as August Beauty, but its blooms are larger and it is a little less cold hardy, Wolfe said.

“Aimee is what florists harvest gardenias from,” he said. “It produces giant blooms, maybe 3 to 4 inches wide, but it is really a Zone 10 plant. If the plant is already struggling, a deep freeze will tip it over the edge without cold protection and it won’t come back.”

Recently, a number of growers have been introducing gardenia hybrids that have found popularity. Heaven Scent is one that Wolfe said sells out as soon as a fresh supply arrives at his nursery.

“It’s one of the new gardenia cultivars with amazing fragrance, with a flower that looks less like a rose and more like a daisy — flat single petals around a prominent yellow center,” he said. “It may be one of the more compact of the gardenias at about 2 feet tall by 2 feet wide.”

To ensure success growing gardenias in the New Orleans area, make sure the soil drains well so that the shrubs don’t “get their feet wet,” as Wolfe said.

Condition alkaline soils with organic matter to improve nutrient uptake. Fertilize with the same food used for azaleas and camellias. And provide the right amount of sunlight.

“Gardenias need six hours a day,” Wolfe said. “If in full sun, they must be fertilized and watered especially through dry spells. The best environment is east facing for morning sun. Everything needs a little protection from afternoon sun in New Orleans.”

R. Stephanie Bruno writes about homes and gardens. Contact her at rstephaniebruno@gmail.com.