Influence of Light and Heated Medium on Rooting and Shoot Growth of Two Foliage Plant Species

Abstract

Ficus benjamina and Codiaeum variegatum ‘Gold Dust’ stem tip cuttings were rooted in a mist bed at 290 or 90 µmols·m–2 Photosynthetic photon flux (PPF) with or without 28° ± 1°C medium heating and then potted. Number of roots in C. variegatum was unaffected by either PPF or medium heating; however, both factors enhanced root elongation. Forty days after potting, cuttings rooted under 290 µmol·s–1·m–2 had more lateral shoots than those rooted under 90 µmol·s-1·m–2 PPF. Although cuttings rooted in heated medium under the lower PPF had roots more than twice as long as those on cuttings rooted in unheated medium under the high PPF, it had little effect on subsequent shoot growth. F. benjamina rooting was improved in heated medium and was not affected by PPF. Unheated cuttings rooted better under high than low PPF. Shoot growth 10 weeks after transplanting was unaffected by the initial differences in root grade.