Showy annual plants from southern Europe belonging to the Daisy family, Compositive. They have simple alternate leaves and branching stems 1 1/2-2 1/2 ft. high, bearing large heads of yellow, yellowish or orange-colored flowers which are in full beauty during the summer. Calendula is derived from calendae, the calends, the first day of the ancient Roman month-an allusion to the almost continuous flowering character of this plant. Calendulas do best in full sunshine and in rather dry soil. They are raised, from seeds sown out of doors in the spring or early autumn where the plants are to bloom the following year and are very easy to cultivate.
The seeds are sown in ordinary soil in a sunny position outdoors in spring to provide flowers during the summer and, in mild climates, in September to furnish plants that will bloom in winter and spring. They may be scattered broadcast or sown in rows 12-16 in. apart. The seeds are covered to a depth of 1/4 in., and the seedlings are thinned, as soon as they are an inch or so high, to about 12 in. apart. The seedlings may be transplanted if desired. Frequent hoeing between the plants is necessary to keep down weeds. The flowering season is prolonged if the flower heads are removed as soon as they begin to fade. The plants from the spring sowing begin to flower in July and continue to bloom all through the summer and far into the autumn except where very hot, humid summers prevail. Such conditions cause Calendulas to produce fewer and smaller flowers or to cease blooming entirely and perhaps even to die. Plants raised from seeds sown in a comparatively cool location in July or August and later transplanted to their flowering quarters will bloom in fall until killing frost. They are
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