As a gladiolus, my life cycle is dictated by the seasons. I am a tender corm, which means I cannot survive freezing temperatures in the ground. Therefore, the optimal time for you to plant me is in the spring, after the last frost date has passed and the soil has warmed to at least 55°F (13°C). I am impatient to grow, but a cold, soggy soil will cause me to rot. I thrive in a well-draining location that receives full, glorious sunlight for at least 6-8 hours a day. My ideal soil is loose, fertile, and slightly acidic to neutral (pH 6.0-7.0). If the soil is heavy clay, please amend it with compost or peat moss to give my roots the airy, comfortable environment they need to explore and anchor my tall form.
Planting depth is critical for my stability and health. A good rule is to place me in a hole that is four times my height. For most of my corm varieties, this means a depth of about 4-6 inches. If you are in a warmer region (USDA zones 8-10), you may plant me a little deeper, around 6-8 inches, to help protect me from the intense heat. Please space us about 6-8 inches apart. We need this personal space to access sufficient nutrients and water from the soil without intense competition. Crowding us can lead to fungal diseases and spindly growth. Remember to place me with my pointed end facing up towards the sun; that is where my shoot will emerge from.
To fuel my rapid growth and support the development of my magnificent flower spike, I require consistent moisture and nutrition. Water me thoroughly after planting to settle the soil around me and eliminate air pockets. As I grow, provide me with about 1 inch of water per week if rainfall is insufficient. I prefer deep, infrequent watering that encourages my roots to grow downward, making me more drought-resistant. Please feed me! A balanced, water-soluble fertilizer (like a 5-10-10 formula) applied when my shoots are about 10 inches tall and again when the flower spike starts to show color will provide the phosphorus I need for spectacular blooms.
My growth is a race against the season. After blooming, my focus shifts from reproduction to regeneration. I begin storing energy in my corm to create new corms for next year. Do not cut down my foliage immediately after the flowers fade. My leaves are my solar panels, and I need them to photosynthesize and replenish my energy stores. Allow my leaves to remain until they turn yellow and die back naturally. In colder regions (USDA zones 7 and below), you must dig me up after the first frost blackens my foliage. Gently brush off the soil, let me dry for a few weeks in a warm, airy place, and then store me in a cool (35-45°F), dry, and dark location for the winter, ready to be planted again when the earth warms.
