By Callen Outen
Spring bulbs, like daffodils, tulips, and hyacinths, will soon begin to fade, and the foliage of the hardy summer bulbs like cannas, gladiolis, dahlias, and lilies will start to emerge. Do not remove the foliage from the faded spring bulbs that have past their prime. The leaves are necessary for photosynthesis to occur, which will produce carbohydrates to be stored in the bulb for next year’s flower production. You should remove old blooms from the spring bulbs. This will allow the plant to send energy towards the bulb instead of producing seeds. Once the fear of frost has past, hardy summer bulbs, such as cannas, gladiolis, dahlias, and lilies, can be planted. When buying bulbs, always choose bulbs that are firm and blemish free. Cannas are a popular plant that have an extended flowering period. Their foliage is available in a wide variety of colors. Most cannas grow 3-6 feet tall. New dwarf cultivars may only reach two feet tall. Cannas bloom from early summer until frost if you remove old blossoms regularly so they do not set seed. Cannas need rich soil and good soil moisture. Plant the rhizomes 1-2 inches deep and 12-24 inches apart. You can divide the rhizomes in the spring if you want to increase your plants.
Gladiolis grow in a wide array of colors and flower best in full sun and most, well-drained soil. Space planting times a week or so apart to have gladiolus in bloom the entire summer. Plant corms 3-6 inches deep and 2-3 inches apart in a row. Rows should be spaced 20-36 inches apart from each other. Gladiolis will need deep watering throughout the growing summer. Avoid daily light watering.
Dahlias are available in a variety of shapes and colors and will bloom from mid-summer until frost. Dahlias prefer full sun and a rich, well-drained soil. Smaller flowering dahlias can be spaced 2 feet apart, while larger flowering dahlias should be spaced 3-4 feet apart. Fertilize monthly with a water-soluble fertilizer. To produce strong, bushy plants, pinch off the tips of the main stems three weeks after planting. To encourage continuous blooming, pinch off faded blooms during the summer months. Lilies are a very popular bulb with over 80 species and several hundred cultivars available. Lilies need well-drained soil and can tolerate sun or part shade. Space lilies 6-10 inches apart and 4-6 inches deep. All bulbs should be mulched to prevent weeds from growing in your bed and to help retain soil moisture. Mulch will also help to keep the roots col.
For more information on Bulbs in the Landscape, please visit the Home and Garden Information Center website at hgic.clemson.edu. Tune in on Tuesday nights to watch “Making it Grow” at 7pm on SCETV or mig.org. Email Outen at callenb@clemson.edu.
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