We, gladiolus, are native to South Africa and the Mediterranean, which means we inherently enjoy warm summers. However, our growth cycle is not solely dependent on heat; it is triggered by a distinct cycle of warm growth followed by a cooler, dormant period. In Florida's consistently warm climate (USDA zones 8-10), this natural cycle is disrupted. The intense, year-round heat can exhaust our corms, and the lack of a pronounced winter chill prevents us from entering a proper dormancy, which is crucial for rejuvenation and next season's bloom.
To thrive in Florida, you must not treat us as a single-season planting. Our corms should be planted in succession, from late fall through early spring. This avoids the most intense summer heat during our critical flowering stage. Plant a new batch of corms every two to three weeks from November to February for a continuous display of blooms from late winter straight through to early summer. Bury us 4 to 6 inches deep in well-draining soil, placing the pointed end facing upwards towards the sun we crave.
Our greatest enemy in Florida's humidity is not the heat itself, but fungal rot fostered by wet conditions. We demand exceptionally well-draining soil. If planted in heavy, water-retentive native soil, our corms will quickly succumb to rot. Amend the planting site generously with organic matter like compost, peat moss, or well-rotted manure. For the best results, consider planting us in raised beds or large containers filled with a light, airy potting mix. This ensures excess water from heavy rains drains away from our sensitive corm base immediately.
We are sun-worshippers and require a minimum of 6-8 hours of direct, full sun daily to fuel our rapid growth and develop strong flower spikes. Water us deeply when the top inch of soil feels dry, but then allow the soil to dry out somewhat before watering again. Constant sogginess is fatal. For nutrition, we are heavy feeders during our growth phase. Feed us with a balanced, water-soluble fertilizer (like a 5-10-10 formula) when our shoots are about 6 inches tall and again just as the flower spike begins to emerge from the leaves.
This is the most crucial adaptation for Florida gardeners. Unlike in cooler zones, you cannot leave us in the ground year-round. The summer heat and rains will cause our corms to rot. Once our foliage has yellowed and died back after blooming, you must carefully lift our corms from the ground. Gently brush off the soil, cut the stem down to an inch, and allow us to cure (dry) in a warm, well-ventilated, and shaded spot for about two to three weeks. After curing, store us in a mesh bag or paper bag in a cool, dark, and dry location until it is time for our next autumn planting. This artificial dormancy mimics our natural cycle and is essential for our survival.
