Liner Propagation Method Influences Growth of Container Grown Bottlebrush

Bottlebrush (Callistemon vinimalis) is a widely propagated and cultivated ornamental large shrub with large red bottlebrush-like flowers. Traditional clonal propagation using stem cuttings may be replaced with tissue cultured liners. In this study, we established a container-grown field experiment of bottlebrush ‘Little John’ using liners propagated from both rooted stem cuttings and tissue culture. Growth index was recorded by propagation method periodically through the 34-week period, and both fresh and dry weights of roots and shoots recorded at experiment’s end. Final growth index of plants grown from tissue cultured liners were significantly greater than growth index of plants started from rooted stem cuttings. Both fresh and dry root weight means were significantly greater in plants propagated by tissue culture. Further testing of containerized bottlebrush production, through the flowering stage, will better determine whether tissue-cultured liners accelerate production time vs. liners from stem cuttings.