Just when I knew there was nothing else to write about, I was asked horticultural questions and the answers should be of interest to a wider audience.

A friend wanted to know why her clivia didn’t flower this year and frankly, I didn’t have an answer. That bothered me, so I read up on clivias. We have grown one for at least forty years and sold the rooted offsets in our flower shops. I knew that they will sometimes produce beautiful flowers and sometimes they just sit there and grow little ones but I had never bothered to go into the subject any deeper.

A native of forest floors of southern Africa, it was brought to England in the 1850s. The plant's ability to survive on shaded forest floors made it well suited to the large, shadowy parlours of Victorian homes. About the only way to kill a clivia would be to drown it. Clivia is a member of the amaryllis family. As with amaryllis, the leaves of a clivia are strongly two-ranked. This means that the long, strap-shaped leaves arise from the soil, directly opposite one another in an alternating sequence, forming what looks like a large flattened vase.

Clivia roots are thick, fleshy and well-equipped for water storage. On a mature specimen the swollen mass of roots often becomes so large that it will completely fill the pot, forcing the growing medium up and over the container's edge. Only when this begins to happen should a clivia plant be moved to a larger pot. In fact, the plants do best when their roots are somewhat constricted by a small pot, so it is best to resist the temptation to place the plant in a pot much larger than the one you are moving it from.

For best results, clivias should be grown in bright but diffused light, with the growing medium kept evenly moist during spring and summer. Ours thrives close to a south-facing window but behind sheer curtains. To encourage the plants to flower allow them to become quite dry for two months in winter while lowering the temperature to 10 - 15°C. The flowers are orange, lily-like, and produced in clusters on top of a thick stem. Once a flower stem has begun to emerge, watering should be increased and plants moved to a warmer location.

Sometimes a mature plant will attempt to flower even when no rest period has been provided. Those flowers are seldom successful because without the proper rest period, the flowering stalk won’t elongate, leaving the cluster of flowers compressed between the leaves near the base of the plant.

Propagation is accomplished almost exclusively by separation of offsets. After three or four years, a plant will have reached maturity. At this point, it will begin to produce one or more offsets each year. When an offset has developed three or four leaves of its own, it can be cut from the parent plant, being careful to include some roots, and placed in a small pot of its own. Clivia plants tend to be long lived, with individual plants surviving ten, twenty or even more years.