Lepidium sativum. The leaves of this unusual cress are flatter than its crinkly cousins, with distinctly serrated margins. The peppery flavour is a touch milder, but still tangy enough for salads and sandwiches. It makes an excellent micro-green. Grow Persian Cress Organic seeds outdoors in early spring and again in the fall and winter. Indoors, it can be grown under lights at any time of the year. Fast growing cress varieties work well in containers and belong in the lexicon of all chefs, both professional and novice Matures in 21 days.