Myriam, your breakdown wouldn't work because we don't think in terms of inches after the first 24 or so. Many roses, for instance, are 3-4 feet tall. Breaking that down into inches (36 to 48) would necessitate the use of two of your categories, and might sound too vague, not to mention being inaccurate as it would imply that these roses are 30-50 inches tall -- too broad a range to be helpful. It also might be just as big a deterrent to using our database, because people would have to convert those inches to feet in their mind.
Unless someone wants to manually add the metric measurements in parentheses to 500,000+ plants at this stage, and I doubt that anyone will, a conversion key seems to be the only answer.
