Before I even made a decent start on the garden I bought quite a few lilies. I grew them in pots the first year and they made me very happy. They were then planted in the garden and happiness has been less abundant. Of course, no garden will suit all lilies and rather wet winter conditions have caused problems too. I was not sure that the Asiatic lilies would thrive because they prefer alkaline soil and my soil is acid. I did actually sprinkle some lime on them but they are fading away. The Orientals, on the other hand, are doing well, as they should since they require acid soil. Of the rest, the OT (tree) lilies and other complex hybrids have largely done reasonably, though, every year, I battle lily beetle and virus is showing up here and there, mostly from the few that were bought from garden centres rather than bulb suppliers.
The exception is ‘Fusion’ which is growing like creeping buttercup (well almost). This is a ‘wide’ hybrid, with the Asian Lilium longiflorum as one parent and the Callifornian L. pardalinum as the other. The result is a very vigorous plant with flowers resembling the American parent but without the fragrance of the white, trumpet-shaped Asian lily. I can’t say that it is my favourite lily but it is showy, much easier to grow than L. pardalinum, seems tolerant of rather wet winter soil and a great garden plant. I wish it was fragrant but you can’t have it all. Anyway, the five bulbs I planted have, over three years, become five clusters of bulbs and now they need to be divided so they have room to grow. They also tend to push themselves to the surface over time and need to be replanted so they are deeper and can root from the stems.
‘In the old days’ lilies were always sold in the autumn because the roots, that grow from the base of the bulbs, should not be allowed to dry out. Lily bulbs are not designed to be out of the ground and dried out. Before my time, long before, Lilium auratum and L. speciosum bulbs were imported from Japan and coated in wax for the long journey. With improved storage conditions the bulbs are usually sold in spring now. You can divide the bulbs at any time when they are dormant but I find it is easier in autumn because there is no risk of damaging the new shoots.
Not all lilies need division that often but Asiatic lilies often produce lots of tiny bulblets at the base of the stems and these can get crowded and need to be separated if they are to have room to grow. I find that OT hybrids do not ‘split’ much at all.
So lift the clumps carefully, making sure you dig deep and lift the clumps, then shake off the soil and cut back the old stems. You can then split the bulbs either singly or into groups of two or three.
Lilies like a soil that is not wet in winter and it is often said to plant them on a bed of sand but this never makes sense to me. Because I have quite a few to plant – the photos above are of a clump that was one bulb – I am replanting in a wide hole that has been dug over with organic matter added. Because roots are produced from the stem, they need to be planted 10-15cm deep. The next important thing to do is to mark where they are planted. If in pots, you will probably need to divide and replant every two or three years. Lilies are hardy and, if in pots, do not need protection from frost.