Some more questions:
1. What are the tomato plants?
2. What are the three spaces?
3. "D to A begins, then a little A to D, then the last D to A". Are you saying this happens from 7 to 6 to 5 to 4? Or from 0->7->6->5->4->3->2->1-0-> and then another 7->6->5->4?
4. Which values to you...