Here’s a question: What do 1-gallon-size ‘Burford’ hollies from every retail garden center in your city have in common?

Greenhouse bedding plants
These greenhouse-grown bedding plants will be sold to retailers. But what sizes will they be labeled?
Photo Credit: David L. Morgan
Container Quercus phellos
It’s easy to go straight for a plant’s looks – but don’t overlook the container label!
Photo Credit: Hahira Nursery
Blue point junipers in containers
If all plants grew equally in size and shape, perhaps container standards wouldn’t be needed.
Photo Credit: Grandiflora™

Give up? Here’s the answer: Maybe nothing.

The reason is we’re not just talking about the plant – it’s the container, too. And here’s why: Since the start of the containerized plant industry in the1940s, pot manufacturers have set their own standards. Being competitive, they’ve designed better and more utilitarian “cans,” each with its own dimensions and, ultimately, capacity. In the absence of regulations, exact quart, gallon, liter and other “standard” sizes were lost in the process. Even more confusing, manufacturers also created their own sizing language. A “junior gallon,” for example, is actually a half-gallon, and a “trade gallon” measures three-quarters of a real gallon.

All of this means that the “2-gallon” holly you purchase from Garden Center A may actually be a smaller plant than the “2-gallon” one you could’ve bought at Garden Center B. Or vice versa.

For obvious reasons, you – the consumer – may feel cheated by these ambiguous notions and become suspect of plant growers and sellers.

Enter the American Nursery & Landscape Association (ANLA). To solidify standards in plant and container sizing, and at the same time bring credibility to the nation’s nursery industry, the ANLA published its American Standard for Nursery Stock, in which definite sizing rules are laid out. Selected plant retailers, have embraced these standards, asking their growers/suppliers to amend their pot-labeling practices to include more specific sizing information.

For example, the 1½- x 2-inch label on a “2-gallon” Norfolk Island pine sold by Lowe’s now gives the container’s true size in gallons (2.33), as well as liters (8.82), and identifies it as a #10-class container. That means it conforms to ANLA standards for that particular size. (many retailers also provide other helpful info on the label, like the proper identity of the plant, its price and the name of the grower. But these extras aren’t prescribed in the ANLA guidelines.)

Not all growers and retailers conform, of course, so it’s up to wise consumers to make their own comparisons as they shop for certain-sized plants for their gardens. If you’re about to make such a purchase, look for plant labels that show the exact container size to be sure you know what you’re getting. (It’s like reading food labels and seeing the exact ingredients and nutritional information – then making an informed decision whether to buy that product based on that extra info.)

The ornamental plant industry – both growers and retailers – hope these container issues will be resolved voluntarily before the states’ weights and measures commissions and federal regulatory agencies impose their own standards.

“We need to grow up,” one ornamental-plant grower suggested. “Other industries have their standards, and we should, too.”

In the meantime, the only rule that stands is caveat emptor – let the buyer beware. And if that buyer is you, keep reading those labels – and learn to shop around.