As all cut flower growers know, finding something new is important in this business. Customers are magnetically attracted to the unfamiliar, and we growers feel the urge to keep expanding our knowledge base. For those reasons, some strange species have made their way into the cut flower business lately. The prime example: Gomphocarpus, the bladder-like seed pods variously known as hairy balls, monkey balls, and bladderbush.

But I don’t want to talk about odd, ugly plant material. I want to talk about a plant that is strikingly beautiful, nostalgic and easy to grow. I’ve been thinking it could be the Next Big Thing in cut flowers.

Coleus is the plant I have in mind. Not the gangly purple thing that trailed from a pot in the window of my dorm room back in the 70s — that one has been relegated to the history books. I’m talking about the new coleus, the tall, bushy, brightly colored coleus that can be grown in full sun. These plants have swept into commerce as container and bedding plants, and consumers are reacting with enthusiasm.

After seeing how tall some of these new coleus varieties get in pots, I decided they might have potential as cuts. So I began preliminary trials this year to find coleus that would appeal to florists and look good in bouquets.

I decided that I would most like to have coleus in fall, when the field-grown annuals are starting to look tired. So I looked for coleus varieties with autumnal colors of copper, bronze, and burgundy. I chose a few chartreuse varieties, too, because that bright green color is always in demand with florists. Next, I looked for varieties that were described as being sun-tolerant. Finally, I looked for varieties that grow taller than 24 inches.

Setting those parameters from the outset is important, because there are so many cultivars of coleus. The website www.coleusfinder.org lists 1,431 cultivars. Many of these are just different names applied to the same plant, but there really is an overwhelming diversity among coleus. The species produces a lot of sports and these mutations are often different enough from the parent that they get named and propagated as a separate cultivar. There’s also some naming and patenting of old cultivars going on.

To wade through the confusion, I turned to Rosy Dawn Gardens, a small mail-order greenhouse in Michigan that sells nothing but coleus, and only from its web site, www.rosydawngardens.com. This is an excellent resource for the aspiring coleus grower. Rosy Dawn Gardens lists more than 200 cultivars of Solenostemon and the similar foliage plant Plectranthus. The online catalog lists cultivars alphabetically and provides a color photo, a verbal description, and a size category.

After spending an hour or so perusing the choices, I chose 16 cultivars. About half were described as sun tolerant; the others I wanted to grow in shade for the sake of comparison. Rosy Dawn Gardens sells only retail, $4.75 per plant, but that was fine for my experiment. There are many wholesale nurseries listed on www.coleusfinder.org but the selection of cultivars wasn’t as large. I figured I can look for a wholesale source after I have narrowed down my choice of cultivars.

I planted the coleus two plants per 5-gallon pot and grew them in various places with different amounts of sunlight. Some were more beautiful to my eye than others. Some were taller than others. But every one of them grew well.
So far, so good. The next part of the trial involved cutting them to determine if they would have adequate vase life. This is where the problems appeared. In some cases, two stems from the same plant would be placed in the same vase; one would wilt immediately and the other would look great for weeks. Those that didn’t wilt would root in the vase. Some cultivars wilted the first time I tested for vase life, but then did fine when I cut it again a month later, perhaps because they were getting less sun, cooler temperatures or shorter days. Some cultivars held their colors in the vase the entire time I had them inside (weeks, in some cases); others started to look dull within a week. According to an article in Greenhouse Product News in December 2005, five varieties of coleus (which weren’t named) were tested for vase life; all five wilted immediately, but after a week rooted and looked fine.
After watching these plants for the entire season, I chose two favorites:

In fall, I cut every stem I could and took them to the florist who buys most of my flowers. He was enthusiastic about the colors and the look. Coleus, he assured me, are trendy. He encouraged me to persevere in my experiments.

So next year, I’ll be growing my two best cultivars from this year in greater quantities, plus trialing another dozen cultivars. I’ll also be trying to figure out postharvest handling — whether water is better than floral perservative; whether the longest lasting stems are older or younger; whether stems that have started to flower hold up better than those that haven’t; whether sun exposure or day length affects vase life.

It’s a lot of trouble, but I think it’s worth it. The colors and patterns of the endlessly variable coleus would be a great addition to a cut flower menu.