Calendula officinalis This old-fashioned flower has a long history as both an ornamental garden plant and as an herb. When dried, the petals of Calendula flowers provide a culinary substitute for saffron; in times past, they were used to give a rich color to cheese or butter. Medicinal uses included treatments for measles and smallpox, as well as for dressing wounds on the battlefield. As well as being the traditional flower for October birthdays, calendula symbolizes sorrow and sympathy. Germination: Direct sow in fall or early spring, planting Â¼ï¿½€ï¿½ below the surface. To start seed indoors, plant Â¼ï¿½€ï¿½ deep in individual pots or a flat; keep evenly moist and at a temperature of 60-65 degrees until germination, which should take place within 5-10 days. Transplant or thin seedlings to 8-10ï¿½€ï¿½ apart. Calendula can adapt to almost any soil, but prefers well-drained, poor or average soil. Since this plant prefers cool temperatures, it will appreciate filtered shade.