Vegetative propagation of Perovskia atriplicifolia

Perovskia atriplicifolia is a beautiful silver-grey half-shrubby plant with a pungent odour, growing 1.0 to 1.5 m high, with blue and white flowers in July and August. The effect of the numerous flowering shoots and the grey foliage is good, and the plant is worth a place in the choicest garden for its graceful habit and long season of beauty. The purpose of this work was to establish the rooting cappacity of Perovskia atriplicifolia. We tested the influence of rooting substrates and the influence of stimulative solutions. The cuttings were rooted under greenhouse and mist, in two different rooting substrates: sand + perlite (2:1) and peat + perlite (2:1) For rooting stimulation, powder and solutions of Rhizopon AA and Rhizopon B, simple or combined in different concentration (50 7 100 mg/L), were used. Rooting performances were expressed in terms of rooting percentage, average root number per rooted cuffing, roots length, average number and shoot length per cutting. Cuttings rooted better in the peat + perlite substrate. The highest rooting percentage (86.66%) was obtained with 50 mg/L Rhizopon AA + Rhizopon B treatment towards of 26.66 rooting percentage obtained on Rhizopon AA powder treatment. Rhizopon AA 100 mg/L treatment on sand + perlite rooting substrate showed best results regarding roots number (7.2 roots/cutting) and roots length (5.4 cm). With the same treatment was registered the highest number of shoots/cutting (2.2) and the longest shoots (23.8 cm).