Many other methods of soilless culture are being used successfully. Some of the media used are peat, vermiculite, perlite, pumice, rice hulls, and plastic Styrofoam. Often mixtures of these media are used in various proportions. Growing trials with various mixtures determine which proportions are most suitable to the plants in question. For example, owering potted plants such as chrysanthemums, poinsettias, and Easter lilies and tropical foliage plants can be grown well in mixtures of peat-sand-pumice in a 2:1:2 ratio.