Colors in the same tonal range or vertical composition? The answer is that they are both. The combination of yellow pincushion protea, dried bird of paradise leaf and hosta leaf are in the same tonal range of yellows. If you look at the chart below you can see the different tones of yellow used in the arrangement.
The arrangement is also a vertical composition, it has movement from the bottom continuing upward in a vertical flow. Vertical composition doesn’t have to be straight lines, it can also have curved lines as long as it has an overall vertical composition.