Propagation from cuttings of two woody ornamental Australian shrubs, Boronia megastigma Nees (brown boronia) and Hypocalymma angustifolium Endl. (white myrtle)

Abstract

Summary. While many woody plant cuttings respond to propagation conditions in similar ways, results presented here indicate that some responses are species specific. Propagation of Boronia megastigma and Hypocalymma angustifolium cuttings was successful except when cuttings were struck without auxin treatment in a pinebark-based propagation medium. More stem H. angustifolium cuttings (100%) produced roots than terminal (shoot tip) cuttings (45.2%). Benzyladenine and gibberellic acid treatment of stock plants decreased endogenous starch concentration and propagation success of both species. Boronia megastigma cuttings propagated poorly when taken in winter when flowers were developing on stock plants. Conversely, adventitious rooting of H. angustifolium had greatest success when cuttings were taken in winter during flower development. Seasonal variation in propagation success may be mediated through changes in the endogenous plant growth regulator or carbohydrate concentrations.