Adventitious rooting and subsequent development of rooted cuttings were evaluated for terminal, single-node, and tip cuttings of catnip (Nepeta cataria L.). During an eight-week production period, cuttings were treated with indole-3-butyric acid (IBA) at 0, 1, 3, and 8 g/kg (0, 1000, 3000, and 8,000 ppm), rooted for one to four weeks, and then grown in the greenhouse for four to seven weeks. At harvest, a first experiment showed that terminal cuttings propagated for four weeks accumulated less shoot dry weight (24 g) than cuttings propagated for two (36 g) or three (31 g) weeks. Terminal cuttings treated with 3 g/kg of IBA and propagated for four weeks had the highest root dry weight, which averaged 12.1 g. In the second experiment, length of the longest shoot and primary root and the number of roots and shoots were greater in single-node cuttings propagated for two or three weeks than those propagated for one week. A third experiment revealed that the development of primary roots in single-node and tip cuttings was similar during a 15-day rooting period.
Contribution of the New Mexico Agricultural Experiment Station, New Mexico State University, Las Cruces.