Lemnaceous plants, namely Lemna minor and Landoltia punctata, have been used in various types of biological research. The effects of Murashige and Skoog (MS) and Hoagland media on vegetative growth rate of both species during in vitro and ex vitro cultivation were investigated. Under axenic conditions, frond proliferation of L. minor and Lan. punctata in Hoagland medium are 8 and 11.5% respectively faster than that in MS medium. Biomass production in Hoagland medium also increases 2.2-fold (L. minor) and 1.4-fold (Lan. punctata) compared to MS medium. The roots of both species in MS medium are distinctly shorter than those in Hoagland medium. In contrast, ex vitro regeneration of frond colonies in MS medium is 22.2% (for L. minor) and 17.1% (for Lan. punctata) faster than in Hoagland medium. Similarly, ex vitro biomass production of both species in MS increases 1.8-fold (for L. minor) and 1.3-fold (for Lan. punctata) compared to that in Hoagland medium. Root elongation of the frond colonies in MS and Hoagland media is comparable. The distinct effects of MS and Hoagland media on vegetative growth of both species and the pre-determination of ex vitro growth rates in each medium are demonstrated.