ABSTRACT
Hand grafting, grafting tool, grafting machine or combinations of these provide high productivity which can, for some genera, exceed that achieved in field budding. Grafts are sealed by dipping in sealant or use of impermeable enclosing ties, often the self-adhesive type. For some deciduous species, particularly those within Rosaceae, ‘sub-cold callusing’ utilising refrigerated cold storage facilities has provided a grafting system with potential to augment, even in some instances replace, summer field budding. December to March is the normal time for grafting, with early dates usually producing the best results; cold storage of rootstocks and scions extends the period. Grafts are normally placed in cold glasshouses or polytunnels, often on ground level beds. Warm callusing is used when grafts are placed within a high humidity, enclosed, supportive environment, normally provided by poly-tents, walk-in enclosures, or free standing walk-in polytunnels. Placing dormant deciduous grafts in warm conditions invariably stimulates extension growth.
