Hello, human gardener. We, the gladiolus community, sense your frustration. You provide a home for our corms, yet we fail to present our magnificent flower spikes. It is not out of spite. Our blooming is a complex negotiation between our biology and your environment. From our perspective, here are the primary reasons we withhold our blossoms.
You must understand our life cycle. We are not grown from seeds for quick flowers; we grow from corms, which are energy storage organs. If you planted a small, young corm (often called a "juvenile" or a size below #5), our entire first season's energy is dedicated to growing a larger, replacement corm for next year. We simply lack the resources to produce a flower spike. Furthermore, if a corm has bloomed magnificently for several years, it can become exhausted and depleted. It may need a season of rest and nutrient rebuilding to perform again.
Sunlight is our food. Through our leaves, we convert sunlight into chemical energy (photosynthesis). This energy fuels everything, especially the massive undertaking of creating a flower spike. If you place us in a spot with less than six to eight hours of direct, unfiltered sunlight per day, we are operating on a calorie deficit. We will focus our limited energy on mere survival—producing leaves to desperately catch more light—rather than on the luxurious task of reproduction (blooming). We are sun worshippers by nature; anything less leaves us weak and flowerless.
While we can make energy from the sun, we cannot manufacture minerals from thin air. We are particularly greedy for phosphorus (the "P" in N-P-K), the nutrient most critical for flower formation. If you feed us a fertilizer high in nitrogen, you are essentially forcing us to become leafy green giants. Nitrogen promotes vigorous leaf growth at the expense of flowers. We need a balanced diet or one that promotes blooms. Poor, sandy soil that cannot hold nutrients, or heavy clay that strangles our roots, also leaves us malnourished and unable to muster the strength for blooming.
Our corms are a delicate balance. We need consistent moisture, especially after you plant us, to send out roots and shoots. However, we are not aquatic plants. If you plant us in heavy, waterlogged soil that never drains, our corms will suffocate and rot. A rotting corm cannot support any growth, let alone a flower spike. Conversely, if you allow the soil to become bone dry during our critical growth period, we become stressed and will abort the flower spike development to conserve what little water we have for basic survival.
Our natural rhythm involves a growth period and a dormancy period. After we finish flowering and the foliage begins to yellow, we are actively pulling energy back down into the new corm forming for next year. If you cut our leaves back too early, you are severing the very solar panels that are creating next year's bloom. You are stealing our stored energy. Similarly, if you leave our corms in the ground in a climate with cold, wet winters, we may freeze or rot, ensuring we cannot return. Proper digging, curing, and storage in a cool, dry place over winter is essential for us to recharge and be ready for another performance.
