Rootstalk Recommendations

Use semi-dwarfing rootstocks, such as M.26, M.9, RN29, and NM.106 (Ontario).

References

  • Cline, J. Commercial Production of Honeycrisp Apples in Ontario. Ministry of Agriculture, Food and Rural Affairs. Factsheet ISSN 1198-712X. http://www.omafra.gov.on.ca/english/crops/facts/05-047.htm
  • As crop density decreases, fruit size and color improves (Wright et al., 2006). Use detailed spur pruning, blossom thinning, and fruit thinning to obtain optimal crop levels. (Embree and Nichols, 2005). Fruit with less than 6 fruit per cm2 trunk cross-sectional area tend to have earlier harvest dates in Nova Scotia. Avoid excessive nitrogen regardless of tree vigor (Nichols et al., 2008).
  • Use NAA at 5 ppm or 2.5 ppm NAA plus 1 pint of Sevin XLR per 100 gal to thin fruit at 10-12 mm (0.4-0.48 inch) growth stage (Schupp, 2003). However, may not get adequate return bloom with thinning at this stage. For stronger thinning, use 5 ppm NAA plus 1 pint Sevin XLR per 100 gal. 
  • Cropload affects fruit size, return bloom, leaf chlorosis, fruit soluble solids content, fruit color, and fruit storage quality (Robinson and Watkins, 2003). For fruit between 200-250 g (7-8.75 oz), New York researchers recommend aiming for a cropload of less than 5 fruits per cm2 trunk cross-sectional area. As cropload increases, get decreases in return bloom, leaf chlorosis, fruit soluble solids content, fruit redness, fruit firmness, bitter pit levels, and postharvest senescent breakdown, rot, and superficial scald, but can get increase in soggy breakdown.
  • Preharvest fruit drop can be a problem in Ontario. Use ReTain to prevent this drop. Preharvest fruit drop is not a problem in western New York (Wargo and Watkins, 2003).