Snapdragon (Antirrhinum majus) The unique flower of the snapdragon spike is a very familiar sight in most gardens. The flowers cover the color range from soft, pastel yellows and pinks to warm red, burgundy and bronze. They flower abundantly from May to frost. The plants come in a variety of sizes and are used for everything from edging borders to tall cutting flowers in the back of a bed. Snapdragons self-sow, yet are rarely intrusive. To maintain well-developed, free-flowering plants, be sure to pinch the plants. Plant snapdragons six to twelve inches apart, depending on the final plant height. Snap dragons like rich, well-drained soil that is high in organic matter. Soil pH should be neutral to slightly alkaline. Plant in full sun. Snapdragons are fairly heat tolerant.
Source: • Connecticut Greenhouse Newsletter #192