Winegrowers Supplies  -  Rootstocks for Grafted Vines

  5BB (Kober)

Adapts to the widest range of soil types. Very fruitful in light soils which are not rich in nutrients. Good for poor stony or shallow soils.
Good tolerance of limestone; can stand up to 40% total, 20% active. Resistant to chlorosis.

Very vigorous growth, it delays the vegetative cycle and is unsuitable for varieties which are prone to coulure / sensitive in flowering (except possibly in light and dry soils).
It easily goes to coulure when planted in soils that produce a lot of shoots and growth; at flowering it gives assimilates to the shoots and leaves and not enough to the embryo clusters.
In very wet years there have been cases of no fruit-set due to over vigour of shoots and leaves.

5BB is often chosen for varieties that are naturally low in vigour, such as Seyval blanc, Siegerrebe and Dunkelfelder.