The vegetables will be planted in a 8ft by 13ft rectangle...OK?

The width of 8 feet = 96 inches...OK?

96 inches accomodates 9 "10 inches" widths...OK?

9 "10 inches" widths accomodates 8 rows...OK?

.................................edge

10

.................................row

10

.................................row

10

.................................row

10

.................................row

10

.................................row

10

.................................row

10

.................................row

10

.................................row

16

.................................edge

Hope that's sufficient for you to visualize this...