The most common reasons for gladiolus not flowering are because of too much shade, too much fertilizer, frost damage and slow draining soils which causes the bulb to rot rather then flower. Gladiolus thrip feeds on sap which can harm flower buds. Gladiolus takes up to three months to flower after planting.

Why is my gladiolus not flowering?

If the area has become overgrown or shaded by a tree or hedge, there will be no blooms on gladiolus since the plant needs full sun to bloom. ... Fertilizer: Newly planted corms may also not bloom because the corms were too small.

Why do my bulbs not flower?

The most common reason for a bulb not flowering is that it has been planted too shallow. Whilst the plant is in leaf, but not flower, is the best time to dig up the bulb and re plant to a greater depth.