The cultural requirements of Lilies are so diverse that only general guidance can be given. The conditions essential for growing Lilies successfully may be generally summarised: a cool rooting medium in open porous soil, perfect drainage and, for most Lilies, shade from hot sun near their roots. These conditions can be readily fulfilled when the bulbs are planted in herbaceous borders or among Azaleas and Rhododendrons. In such positions, the young spring growth is protected from cold winds and the ground is kept cool by the shade of the surrounding plants. This is especially needful in the case of those Lilies which make stem roots, as these are only developed freely in shade. The majority of Lilies should be planted 15-23cm (6-9”) apart, 15cm (6”) deep. Surrounding the bulb with sand helps drainage and discourages slugs. Lilies are remarkably resilient to drought but should never be allowed to dry out. Nor do they want to be sitting in a container without drainage, where a period of rain is going to drown them. Most Lilies grow well in pots. Make sure they are deep enough to allow at least 10cm (4”) of soil above the bulb and use a humus-rich compost. Give liquid feed in the summer. Remove faded flowers as necessary, but don’t cut back the whole stalk until the autumn. Top dress with new soil each spring and re-pot every two years.
The scarlet lily beetle is a growing menace. Spray as soon as you spot any conspicuous adult beetles or their larvae, which are hump-backed reddish-yellow and covered in black slime; these appear from May onwards.