How to Fertilize sword lily 'Black Jack'?
Weak bulb potash feed monthly before summer flower stalk emergence

sword lily 'Black Jack' · Gladiolus 'Black Jack'
Grow in fertile, well-drained soil in full sun, planting the corms 15cm deep in spring, on a bed of sharp sand to aid drainage; in frost-prone areas, lift when the leaves turn yellow-brown, and store the new corms in a dry, frost-free place until the following spring; in milder areas, add a thick dry mulch over winter
Weak bulb potash feed monthly before summer flower stalk emergence