Some popular garden perennials yield low numbers of viable cuttings per stock plant or produce cuttings that are slow to root, preventing propagators from meeting demand for rooted liners. We quantified the effects of a range of nitrogen (N) rates from 0 to 300 mg·L−1 N applied to stock plants on the number of cuttings (yield), rooting percentage, and subsequent root development of cuttings. Species studied include ‘Siskiyou Pink’ gaura (Gaura lindheimeri), ‘Pixie Star’ dianthus (Dianthus alpinus), perovskia (Perovskia atriplicifolia), and ‘Mainacht’ salvia (Salvia ×sylvestris). We found 100 to 150 mg·L−1 N to be the best rates for producing quality rooted cuttings. Little benefit was obtained from the higher rates, and the 0- and 50-mg·L−1 N treatments produced the lowest number of potential cuttings across all species.
Kiwifruit (Actinidia deliciosa) propagation: Influence of stock plant sexuality on root development