Size can vary from source to source.
They also have a large, well-developed root system. Grade 1 plants must be 2 years old when harvested from the field. These are generally premium-priced rose plants. They are often plants with very small canes, often substandard, and are usually not worth the extra effort required to nurse them along. It is usually better to buy several Grade 1 roses each year than a dozen inferior plants that may never result in good garden specimens.