Gladiolus ‘Red’. Gladiolus are real summer bloomers that can bloom until autumn. This rich flowering, large-flowered gladiolus grows to 100 cm and is also a wonderful cut flower. So be sure to plant a row of gladiolus in your cut flower garden. gladioli are very floriferous and should therefore not be missing in your summer flower garden. You can plant the gladiolus tubers about 7-10 cm deep in the spring. First loosen the soil well and sprinkle a layer of sharp sand at the bottom of the planting hole. This allows rainwater to drain well under the tubers. Space the tubers about 10-12 cm apart. Add some good potting soil when planting. Mix heavy (clay) soil with sharp sand before planting. This large-flowered gladiolus likes to grow in a warm sunny spot. This large-flowered gladiolus is easy to combine. You can make special combinations with it in the border with tall perennials and dahlias. Preferably plant gladioli in a different spot every year.