2018 ASHS Annual Conference

Budding and micropropagation are the typical clonal propagation methods for difficult-to-root nursery crops. These methods can be more time consuming and expensive that cutting propagation. The forestry industry has adopted a commercially viable hydroponic stock plant strategy for difficult-to-root species that emphasizes plant nutrition and juvenility to establish cuttings that root at high percentages. A similar system was developed for a difficult-to-root nursery crops using eastern redbud (Cercis canadensis) as a model. Redbud stock plants grow vigorously in the modified hydroponic sand beds. It was determined that plants responded equally well when irrigated at full or half-strength nutrient solutions. Stock plants produce shoot growth that permitted cutting harvest every two to three weeks. The highest rooting for seedling and clonal cuttings was at 10,000 and 15,000 ppm auxin as a quick dip. Rooting was very similar for cuttings taken from hedged greenhouse and field-grown stock plants. Seedling cuttings were easier to root compared to cuttings from clonal plants. The highest rooting for clones was approximately 30% compared to 55% rooting in cuttings from seedling stock plants. Also, ‘Oklahoma’ cuttings consistently rooted at lower percentages than ‘Appalachian Red’. This research is supported by a grant from the Horticultural Research Institute.