Gladiolus

Lift the gladiolus corms before the first frost (from about mid-October to early November, when the foliage wilts), leave them to dry for one to two weeks in an airy, frost-free place and sort out soft or rotten corms. Store the healthy corms over winter dry, dark and frost-free at around 5 to 8 degrees (for example in a cellar) and plant them out again from late April, when frosts are no longer a threat.

The simplest and most reliable method is propagation by cormlets: when you lift the corms in autumn, about six weeks after flowering and by early October at the latest, you will find numerous small daughter corms at the base of the mother corm. Carefully separate these by hand, keep mainly the largest ones (about pea to marble size), leave them to dry for a few days in an airy place and store them over winter frost-free, cool and dry (ideally at around 5 to 8 °C), best in paper bags or loosely in sand. From late April, after the Ice Saints (mid-May), plant the cormlets about 5 to 8 cm deep outdoors. Allow two to three years of patience until the daughter corms are able to flower. In the first years they only form leaves and gather strength.

Alternatively, you can divide large, strong mother corms with several clearly visible eyes in spring shortly before planting. Cut the corm with a clean, sharp knife so that each piece has at least one eye AND a piece of the basal plate (the flat underside from which the roots grow). Without a basal plate the piece will not root. Let the cut surfaces dry briefly before you plant the pieces. This method gives plants that can flower sooner than growing on cormlets.

Trueness to cultivar is guaranteed with both methods, since you are propagating vegetatively. Do not propagate garden gladioli from seed. As Gladiolus × hortulanus is a hybrid, the seedlings do not match the parent cultivar and mostly show unpredictable colours.