Trial Gardens: How New Plants Make It to Your Home Garden

Plants go through years of breeding and testing before they land in commercial garden centers. Find out how a plant makes it from the greenhouse to your house.

Photo by: Tomas Espinoza Photography

Tomas Espinoza Photography

Developing a new plant variety is a lengthy process. In fact, it takes several years for a new plant variety to show up in a garden center. Have you ever wondered how plant growers gather information about the growing habits of plants in different growing zones? The answer is trial gardens.

Photo by: Tomas Espinoza Photography

Tomas Espinoza Photography

What is a Trial Garden?

It is a garden grown specifically for the purpose of testing and evaluating new plants. These gardens are operated by universities, plant breeders and garden-industry companies as well as private citizens and botanical gardens. The purpose of trial gardens is to make sure plants will thrive in home gardens. Brandon Coker, Trial Garden Manager at the University of Georgia says, “The purpose of trial gardens is pretty substantial in getting people what they need.”

Photo by: Tomas Espinoza Photography

Tomas Espinoza Photography

How Does a Trial Garden Work

There are about 42 trial gardens in the United States. Of the 42, roughly 16 are university trial sites. When a breeder is satisfied with a plant they developed, they send it to a trial site. The trial site is selected based on the growing conditions needed for the plant. For example, if the breeder wants to know how well the plant tolerates heat and humidity, it’s sent to a trial site somewhere in the Southeast. If they want to test it in an arid mountain environment, they will go out West.

Photo by: Tomas Espinoza Photography

Tomas Espinoza Photography

Before a plant lands at a trial garden, the breeders have already spent years developing and testing it. A trial garden is typically the last line of analysis before it shows up in garden centers. But that doesn’t mean it will be available to consumers in the next growing season. “I've actually had multiple plants that I've trialed more than one year in a row,” explains Coker. The breeder wants to make sure how the stock will grow in a “home setting” so they may require more than one growing season to determine the best selection of plants that customers will have the most success.

Seedlings in Greenhouse at UGA Trial Garden

Seedlings in Greenhouse at UGA Trial Garden

Photo by: Brandon Coker

Brandon Coker

Trial gardens don't just test starter plants — they also test seeds. Many gardens are equipped with production greenhouses to start seeds and monitor the seed's integrity before planting them outdoors.

Why Trial Gardens are Important for Consumers

When a consumer purchases a plant, they want it to be beautiful as well as hardy. If plant breeders want consumers to spend their hard-earned money on plants, they have to ensure that it will grow well. Trial sites report all information gathered during the growing season and the grower makes adjustments if needed.

Photo by: Kurt Reynolds

Kurt Reynolds

For the most part, by the time plants makes it to trial, the plant breeder is pretty sure that it will go to market. However, there are times that additional information cannot be determined until the plant spends a season or two in the ground. Coker explains, “We’ve had a variety of plants that look great to begin with, and then as the summer wears on them, they can quickly go downhill.” All of this effort is done to make sure that the plant will be successful for the consumer. The plants that do pass trial will typically show up in garden centers the following season. Some popular varieties tested at University of Georgia are Coleus Flame Thrower 'Spiced Curry' and 'Salsa Verde,' Pentas Lucky Star 'Pink' and 'Violet,' Petunia Vista 'Fuchsia' and 'Pink,' Geranium Calliope 'Large Dark Red' and 'Large Rose Mega Splash' and Salvia Skyscraper 'Pink' and 'Orange.'

Photo by: Tomas Espinoza Photography

Tomas Espinoza Photography

How to Support a Trial Garden

Most trial gardens are non-profit. They exist to gather and provide information that benefits both consumers and plant growers. If you are a plant lover, the best way to support your local trial garden is to visit. Most university trial gardens are open to the public and offer free admission and you will get to witness new plant varieties in action.

Many trial gardens will also have annual plant sales to help raise funds for the gardens. This is a great opportunity to get top-notch annuals and perennials at great prices. Of course, many trial gardens will gladly accept donations of cash, garden items and volunteer hours. Other organizations that have trial gardens include the University of Tennesse, University of Michigan, Colorado State University and the Dallas Arboretum and Botanical Garden. To find a trial garden near you, check with your local university, botanical garden or plant grower’s website.

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