Propagation of Selected Culinary and Ornamental Herbs

Abstract

Ten culinary and ornamental herbs were evaluated for time and quality of rooting of tip cuttings. The taxa included in the study were oregano (Origanum vulgare), lemon thyme (Thymus ×citriodorata), applemint (Mentha suavolens), Persian catnip (Nepeta ×faassenii), lemon balm (Melissa officinalis), southernwood (Artemisia abrotanum), caraway thyme (Thymus herba-barona), hyssop (Hyssopus officinalis), `Blue Wonder' catnip (Nepeta `Blue Wonder'), pineapplemint (Mentha suavolens var. variegata). Four replicates of each species were used. The cuttings, untreated and rooting hormone treated, were placed under intermittent mist, then cuttings potted when a 1- to 1.5-inch root ball had developed. Most of the stock suffered from some chlorosis during rooting; southernwood cuttings particularly displayed severe chlorosis which was overcome with 2 weeks of constant-feed fertilizer after potting. Oregano displayed the best results, rooting in seven days with or without treatment. It produced a sellable 4-inch pot in 31 days from sticking the cuttings. Lemon thyme, applemint, Persian catnip, and lemon balm all rooted in 14 days if treated. No difference was observed in days to rooting between treated and untreated lemon thyme. Untreated cuttings of lemon balm, applemint, and Persian catnip rooted in 25 to 30 days. Treated applemint cuttings not only rooted more quickly but produced a marketable 4-inch pot in significantly less time. Southernwood and caraway thyme rooted in 25 days, with no significant difference between treated and untreated cuttings. Hyssop, pineapplemint, and `Blue Wonder' catnip took about 30 days, also with no significant difference between treated and untreated cuttings.