The vines in Alsace are taller than in the southern regions to benefit from maximum sun exposure all year round. Their average height reaches about 6 ft (1.80 to 1.90 m). They are trellised on five wires that maintain the foliage, a system favorable to the good maturation of the grapes. Depending on the planting density, the number of buds per branch is variable. There are 4,500 to 5,000 vines per 2.5 acres (1 ha) in the region. Line spacing is 5 ft (1.50 m), and spacing between stumps is around 4.5 ft (1.40 m). Winegrowers are currently experimenting with a 6.5 ft (2 m) spacing between vines lines.