Gladiolus is a classic perennial known for its tall flower spikes and large, colorful blooms. Great cutting flowers, gladioli look spectacular in summer bouquets. Hereâs how to grow gladioli in your garden.Commonly called âglads,â these lovely flowering plants are available in a multitude of colors and typically reach between 2 and 5 feet in height. Their blooms also range in sizeâfrom âminiatureâ flowers less than 3 inches in diameter, to âgiantâ flowers greater than 5 inches across!
Water the gladioli once or twice weekly, or when the top 1 to 2 inches of soil begins to feel dry. Provide about 1 inch of water weekly during dry weather. Cover the soil with a 2-inch layer of mulch, and replenish it each spring, to help retain soil moisture.
Apply a slow-release 5-10-10 or 10-10-10 fertilizer every month after new growth emerges each spring. Apply 1 tablespoon of the fertilizer to every 1 square foot of gladioli bed, sprinkling it on top the soil 6 inches from the plants. Water after application so the nutrients soak down to the roots.
Cut back the gladioli to within 1 inch of the ground in fall when they yellow and die down naturally. Dispose of the removed plant debris so it doesn't harbor pests in the winter garden.