Essentially flourishing

Photography by Mindy Young

Brent Horvath, plant breeder and second-generation owner of Intrinsic Perennial Gardens, almost tinkered with engines instead of plants.

Despite growing up in the green industry and working at his family’s garden center and landscape firm, his love of muscle cars — specifically his ’69 Camaro Z28 — pushed him toward a career as a mechanic.

But a horticulture class steered him back onto the road to plants when he realized how easy the subject was for him.

Instead of auto mechanic trade school, Horvath enrolled in horticulture at Oregon State University in 1987. He also interned at W. & E. Radtke in Germantown, Wisconsin. His experience at the perennial nursery helped pique his interest in the crop and made George Radtke a mentor. Horvath says Radtke helped shape his love of perennials after his dad, Lajos, created the spark.

“That was a great experience. I really got the gist of what it meant to be in a wholesale production nursery,” he explains. “They were great plantspeople, and I learned a lot there. Many of my techniques I use today are based on things I learned at Radtke.”

When Horvath graduated in 1991, he returned to Hebron, Illinois, and started the wholesale nursery as a division of the family’s landscape company, which his brother and father were running. Horvath’s father had been growing and selling perennials since the 1980s. And even as a child hanging out in the family’s garden center, he was always drawn to the beauty of perennials.

“It’s not just the flowers, but the textures and the sizes. It’s almost mind-boggling how many possibilities there are with perennials,” he says.

Soon after he started the production nursery, Horvath read the book “Perennials” by Alan Bloom, which chronicled how Blooms of Bressingham was responsible for some of the most well-known perennials in the trade, such as Autumn Joy sedum and Moonshine yarrow. That was the catalyst that drove him to develop and breed perennials.

“They were doing so much developing, breeding and introducing of perennials, and they were the first to really create a brand,” Horvath remembers. “As soon as I read that book, I said, ‘This is what I want to do. I want to find and create new perennials and bring them to market.’”

A new path created

In the mid-1990s, perennials such as daylily Stella d’Oro and scabiosa Butterfly Blue were big sellers at Intrinsic, and the industry buzzwords were “ever-bloom” or “rebloom,” Horvath recalls.

“So, that was an initial focus in my breeding. I started with Geum because I thought it was possible through breeding to get an ever-blooming selection.”

Horvath’s first patented plant was Sedum Autumn Charm (‘Lajos’) a variegated selection of Autumn Joy, and he thought it would be a game changer, recalling “When I found it, I thought, ‘Oh, my gosh. This is going to be one of the top-selling perennials out there.’”

He discovered that wins and losses are part of the challenge of breeding. “It didn’t take off,” Horvath says of his sedum. “It never really came to fruition. Variegated plants weren’t as popular, and it was less vigorous.”

Horvath looked at what was popular in the trade to find his next focus.

“Some of the plants that were big sellers were what I called ‘fashion plants’ — they may have been perennial in nature in the right conditions, but they may not have been overly perennial in the garden. Gaillardia is a good example. It’s a great plant, it blooms a long time, it looks great in a pot, but the bulk of Midwest gardens can’t really grow it or make it survive without amending it to either sandy or rocky soil,” he explains.

Horvath switched his breeding efforts away from short-lived plants and focused on durability, a characteristic that now dominates his selections.

“I breed for survivability and durability in the Midwest, where conditions are both cold, wet winters and hot, humid summers,” he explains. “So, our conditions are good for proving plants’ worth.”

Durability to Horvath means hardy and disease resistant, as well as the ability to grow in a more natural way at the nursery.

“That means growing in relatively lean soils without the use of fungicides and tolerant of overhead irrigation,” he says.

Those characteristics helped him discover and release Rudbeckia ‘American Gold Rush’.

“I couldn’t grow ‘Goldsturm’ anymore because of its susceptibility to Septoria leaf spot. It was a top-selling plant, so I had to figure out something. From that breeding came ‘American Gold Rush’, which is resistant to Septoria, even in wet and humid conditions,” he explains.

That selection was also named the 2023 Perennial Plant of the Year by the Perennial Plant Association, with another of his selections to be announced in July 2025.

Durability also has nuances, such as a natural habit with a good presence in the garden — something that doesn’t flop and doesn’t overly reseed, he says. “I start with durability in my breeding, then move on to other typical breeding goals like new forms, new colors or new sizes. I’m definitely not focused on short plants. I wouldn’t say I’m focused on tall plants, but I probably have more tall plants than most breeders. In the shrub world, it does seem like they’re getting smaller and smaller, but that’s certainly not a focus of mine.”

Durability led Horvath to introduce several ornamental grasses, including Andropogon gerardii ‘Blackhawks’, Bouteloua gracilis ‘Honeycomb’, Carex pensylvanica ‘Straw Hat’, Panicum virgatum ‘Prairie Dog’ and Pennisetum alopecuroides ‘Love and Rockets’. And there are more grasses in the pipeline, due in part to the naturalistic garden trend and their durable characteristics.

“The naturalistic garden trend is still really building, and it’s not regional anymore; it’s worldwide. A lot of that has been inspired by Piet Oudolf and proteges or associates of his, like Roy Diblik, Austin Eischeid and Kelly Norris, who are building these big public and private naturalistic gardens,” he says. “We are surrounded by naturalistic gardeners, including friends and customers and mentors, as well. So, it’s definitely a big part of my work now. A lot of our great grasses are native prairie grasses. They’re just naturally durable, tough, hardy and easy. I love them.”

For the past 10 years, Intrinsic Perennial Gardens has hosted an Ornamental Grass Day, which continues to gain momentum, Horvath says.

From concept to trials

When Horvath initially conceptualizes a breeding idea, he must first assemble the parents or genetic material. Sometimes, that entails buying plants at retail or purchasing seed. Sometimes, they’re wild collections of something that caught his eye.

“Once we assemble that genetic material, then we can start putting it into some order to either hand-cross them or let the bees or wind move the pollen about within the group,” he explains. “Once we have a wide selection of plants, whether it be all in the same species or different species, next is collecting and cleaning seed once there are crosses. That’s a big step. If we miss collecting, then that can set us back a year.”

Horvath and his team put seedlings into individual plugs, which are placed into individual pots.

“Once we have them in a pot, we can compare them to existing cultivars and to their sister seedlings. At that point, if we see something we like, we will generally give it a preliminary name and begin the process of what it takes to bring a plant to market,” he says.

Next, they propagate it and make up to 50 plants, which allows them to get a better read on it. More comparisons happen at this stage, and it’s planted into the trial garden. More plants are propagated and shared with others for trialing, whether that’s at a public garden or a grower from their network of licensees.

Having those additional sets of eyes on the plant often helps expand Horvath’s initial view of the selection.

“My focus may have been on the durability and disease resistance, but someone else may see it’s easy to propagate, or another may see it as a new habit in the garden. That’s the beauty of having different people trial and grow them — we all see the plant for something different. I do like when my plants can speak for themselves, but it’s important to communicate those benefits so the consumer doesn’t think it’s a subtle change to something they’ve already seen in the market,” he adds.

Once Horvath receives feedback from the trials outside of his own space, he’s got a good idea of which direction to take it.

“At that point, we’ve made a pretty good determination of the plant and will decide if we’ll bring it to market or stop growing it,” he says. “If we are going to introduce it, we have to start looking at the supply chain, which has three main situations: tissue culture, division and cutting propagation. Seed is a fourth option. We have a few strains but do not have those in the supply chain yet, so we collect and sell those plant strains locally.”

Once they bulk up to around 2,000 plants, IPG looks at suppliers.

“If it’s an unrooted cutting item, like a monarda, we work closely with Quality Cuttings in Ohio, which has a farm in Mexico, or Danziger in Guatemala and Kenya. For tissue culture, we work with about six labs throughout the world. Three are domestic, and three are in the EU. But we have items in some other labs and some new relationships building, as well,” he says.

Horvath recently released Scirpus pendulus ‘Stars and Stripes’, a rush that looks more like a Carex, he says.

“The bulk of that genera are used as native wetland plants, and there wasn’t a real ornamental form for the trade yet,” he says. “But we’re getting a lot of interest in it. I think it will get people’s attention because it’s a plant many aren’t familiar with.”

Horvath has a big “pet plant” succulent collection, including some Crassula, so there is potential for some tender succulent introductions in the future. But that’s just a fun side gig, so to speak. He’s also looking at a few ornamental grasses that wouldn’t be considered hardy but still have their place in the market.

Kelli Rodda is editorial director of Greenhouse Management magazine. Contact her at krodda@gie.net.