The Rose Grading System
The American Association of Nurserymen, an organization I belonged to for many years, released the following information on how rose plants are graded for sale. Back when I was working for a nursery when I was in my mid-20s, our nursery bought #2 bare root roses which came in large cartons. The nursery bought from a reliably good rose grower who always gave us better than #2 roses.
Our job was to trim off any broken roots or canes, put each plant into a 2 gallon pot and fill it with our own homemade potting soil. The roses were then put in the garden center shelter and mulched until the weather began to warm. We would then line them out in the sales area where they would leaf out and start blooming around Mother's Day. You might keep the grading system in mind when you shop for rose bushes. The better the grade, the more healthy and robust the plant will be. If you buy your roses at a discount store, you are assured of the lowest quality, culled-out rose plants. (The kind of root graft also has a lot to do with how strong, hardy and robust a plant will be, and cheap roses have a poor quality rose root graft which is why many are not reliably hardy). Here's the commercial grading system that commercial rose growers and buyers use:
Grade #1 - The Best Grade of Rose available commercially
Hybrid Teas and Grandifloras must have three or more “strong canes,” two of which are at least 18 in. long. The canes should be well-spaced around the graft (rather than all on one side).
Floribundas meet the same standards, but the canes need only be 15 in. long.
Polyanthas must have four or more canes at least 12 in. long.
Climbers and ramblers must have three or more canes 24 in. long.
Note: “Strong canes” is not defined, but is generally accepted to mean canes which have attained their mature size in diameter. As a minimum, at least one cane must be at least 1/2 in. in diameter.
Grade #1 1/2
Hybrid Teas and Grandifloras must have two or more canes at least 15 in. long.
Floribundas must have two or more canes 14 in. long.
Climbers must have two or more canes 18 in. long.
Note: Polyanthas that do not meet Grade 1 standards are not graded.
All classes must have two or more canes 12 in. long.
However, the mass-market rose producers have their own grading system. They use an arbitrary numbering system that has little or nothing to do with the standard grading system, so just because the package at K-Mart says "#2" doesn't mean it actually conforms to the grading system used by quality rose growers.
Here's what we used to get at the nursery in big cartons, wrapped in peat moss. A rose bush you buy should have a vigorous, strong root system for you to have success. If it's a plant that's all wrapped tight in a little tube, or you can wrap your fingers around the package where the roots are, you don't have enough roots to have a good plant. Don't waste your money on cheap rose bushes, you are assured of being disappointed. Buy a well-established plant from nurseries that observe the quality grading systems. I've bought many times from Antique Rose Emporium and can highly recommend their roses.