CANNA Terra Professional is a nitrogen-rich potting mix for plant cultivation. Your plants grow best in a nitrogen-rich potting mix. CANNA Terra Professional potting mix is unlike anything you will find in a garden centre. It contains a blend of sphagnum moss peat, compost, worm castings, perlite and a special ‘natural plant booster’ which is a blend of organic ingredients. If you are going to grow indoors or outdoors, this is the potting mix you want to use.