Vine growth balance – Internodal distance and Root:Shoot Relationship
As a liana plant the wild vine initially grows in the semi-shadow of a tree. Here, poor light, a damp climate and little aeration are predominant. The plant’s aim is to grow faster than the tree and to spread itself in the tree’s crown. The vine develops a strong leader shoot in this environment.
Vineshelters recreate this "optimum", stress free environment.
The amount of growth experienced varies significantly from situation to situation, but the difference between a vine grown within a shelter and outside is consistently obvious. Early evidence of shelter performance indicated incremental growth of between x2 and x4 that of a control sample. Growth of up to 5cm per day has been observed. A vine can reach a trellis wire, height 1m, in just 3 weeks after planting, and ready for pruning in the first season.
Crops of between 3 – 4.5 tons per acre (7.5 – 11.25 tonnes per ha) have been achieved just 18 months after planting, even after cluster thinning to avoid overcropping.
However, the following factors will limit growth, even if a shelter is used:
- Poor soil preparation, over compaction of roots;
- Overwatering is the most common management error seen with vine shelters. Watering in excess of field capacity reduces soil oxygen. Overwatering is a common cause of shoot burn or, in less severe cases, reduced growth.