Nothing says springtime like freshly blooming flowers, but for many gardeners, the winter is simply too dreary and gray. Forcing bulbs such as the gladiolus to bloom indoors can add a bit of spring to the long winter months.
"Forcing" is the term used to describe the process of encouraging a bulb to bloom out of season. Once a bulb has bloomed, the leaves of the plant continue to make food via photosynthesis. The plant stores the food in the bulb for the next season. Forcing the bulb is tricking the plant into thinking it has survived winter and that spring has arrived. Forcing spring bulbs, such as the Hardy Gladiolus, is a way to enjoy a dose of spring color any time of year.
Familiar in formal flower arrangements, gladiolus are easy-to-grow summer blooming plants. Commonly planted in the spring in U.S. Department of Agriculture zones 7 through 10, many varieties of gladiolus are not suitable for forcing. The Hardy Gladiolus is more cold hardy than other glad species and is an ideal choice for forcing.
To force a gladiolus, begin with healthy, well-shaped bulbs from a garden center or dug out of the yard. Place the bulbs in shallow pots filled with soil-less potting medium, setting them so that the tips are just at or slightly above the surface of the soil. Water the bulbs thoroughly. Set them in a cool place such as a root cellar or refrigerator. Leave the pots in the cold for three to four months, keeping the medium moist. To force the plants to bloom, remove them from the cold and place them in a warm, sunny location or under grow lights.