Calendula officinalis. Maayan Dark Orange Organic Calendula seeds produce lovely, dark red/orange, fully double flowers with a ruffled look on highly branched, sturdy plants. These compact annuals grow to about 45-51cm (18-20″) tall. Calendula is easy to start from seed either in the spring or from overwintered fall plantings. It may self-sow in mild areas, but it’s easy to control and will not become weedy. This drought-tolerant plant is a good candidate for xeriscaping and requires little care once established. It’s also really nice in patio containers where it can be kept carefully deadheaded and tidy looking.