This time of year, Lois Stack is a Black Magic woman.

Black Magic Rose geraniums, that is. The flowers are among the 2002 All-America Selections winners on view at Rogers Farm in Stillwater. Stack and a group of volunteers tend to hundreds of plants in the farm’s two display plots, where gardeners and greenhouse owners can preview annuals that will fill nurseries and seed catalogs next year.

“Gardeners love new plants, so that’s a very important part of what we do,” said Stack, an ornamental horticulture specialist with the University of Maine Cooperative Extension. “If you’re thinking of next year’s garden and you’re trying to visualize a plant’s potential, it’s a good time to stop by.”

The plants are in full bloom now, with cascades of petunias and fiery chili peppers filling the gardens with color. There are fruits, vegetables, flowers and foliage with names such as Lavender Wave (a petunia), Orange Smoothie (a pumpkin), and Black Heart (an ornamental sweet potato vine).

The Cooperative Extension’s display garden program started in 1988. Each year, the Extension has grown two groups of plants in side-by-side plots. One garden shows the All-America Selections winners from the previous five years as well as those that will be introduced in the coming year. These are propagated from seed. The other garden shows “vegetative annuals.” Don’t let the name fool you, though. These plants are grown primarily for their flowers, not their vegetation. “Vegetative annual” is synonymous with “clone” – they are started from cuttings and each new plant is genetically identical to the plant from which it came.

Plant breeders submit seeds to All-America Selections, a nonprofit group that sends the seeds to independent, unpaid judges who evaluate the plants for hardiness, color, flavor, resistance to pests and disease, earliness to bloom, yield, length of flowering or harvest and overall performance. Very few (about 10 a year) make the cut.

“If it’s judged to be a superior plant, a unique plant, it is identified as an AAS winner,” Stack said. “It means that that plant has performed so well in so many locations. For a gardener, that’s a pretty good recommendation. You can expect that plant to do well.”

Though there is a trial site in Maine – Johnny’s Selected Seeds in Albion – that doesn’t guarantee every winner will be a smashing success here. The Maine growing season is one of the shortest and coolest in the country. Seeing how the plants perform in the display garden is one way to gauge how they’ll fare in your back yard.

“Almost without exception, of the plants I would expect to succeed with in Maine … the AAS winners have been superior to others on the market,” Stack said. “There are always some plants that you just have to use common sense on.”

You don’t have to worry when you plant Bright Lights Swiss chard or Baby Bear pumpkins, though. Robert Johnston Jr., who owns Johnny’s Selected Seeds, introduced those AAS winners in recent years.

“It’s kind of neat to say that a plant was introduced by a gardening company in Maine,” Stack said.

While fruits and vegetables are well-represented in the All-America Selections garden (located on the left when you walk onto the farm), the other plot is geared more toward container plants. In the vegetative-annual garden (on the right), the focus is on vibrant foliage or compact, fast-growing, bushier plants that flower early and often. That means you’ll see a lot of petunias, coleus and verbena, along with a few less-common varieties, such as the Tiny Mice cuphea, which hides its little red flower “heads” under the leaves.

“They’re capable of filling out a container and really look lush,” Stack said. “They’re constant color for the rest of the season.”

All the plants in this garden are patented and sold under brand names such as the familiar Proven Winners. In the past 10 years, demand for these plants has skyrocketed. Stack attributes this to busy lifestyles, lack of gardening space for people who live in apartments, and the plants’ relatively low maintenance.

“This industry has started in response to the gardening popularity of containers,” Stack said. “That’s become quite a large part of the industry [and] that has created a demand for plants that do well under those conditions.”

Stack grows them to show the public and people in the industry how the plants perform. That way, she can give recommendations to greenhouse and nursery owners or warn them when a plant has problems such as susceptibility to disease.

“By the time a grower in Maine would start growing these plants, I’ve already gone through it,” Stack said. “I know some of those things about a plant because I’m a year ahead.”

Though Stack is a gardening guru, there are so many new developments in the industry, that even she can’t keep up with them all. For her, managing the display plots at the university’s farm helps keep her current.

“This industry has changed so much that there are whole groups of plants that I’ve never heard of before, even though I studied plants and taught horticulture at the university,” Stack said. “It’s a great learning experience.”

Lois Stack loves giving garden tours. For more information or to schedule a tour, call her at (800) 870-7270. The display gardens are located at Rogers Farm on the Bennoch Road in Stillwater (between Stillwater Avenue and Route 43). The gardens are open to the public and all plants are marked. Plant lists are available free of charge in a box at the entrance to the garden. If you go, be sure to bring a pen and paper.