Facts about the Growth of Clivias

Nicholas Primich
October 2000

It is not given to man to know everything, but he can certainly attain a far higher level of information if he applies himself. Your two botanists, who claimed to be unaware of how this phenomenon of horizontal, instead of vertical striping occurred, were just not inclined to go to the literature to find out exactly how it happens.

 In 1998 I attempted by transliteration to present to our members a clearer understanding of the behavior of variegation in clivia. That I did not succeed became obvious to me when people spoke to me afterwards about it and told me they could understand nothing of what I was writing about. Perhaps if I practiced it more often, I would develop a clearer and more readily understood style of writing. I will attempt to do so, and if there is anything I say that is not clear and readily understood, please let me know and I will rephrase it until it is understood.

In our clivia, the main growth comes from the apical meristem. Here leaves are generated on a regular basis, with flowers being formed every fourth leaf or so. The meristem is inside the bulb of the clivia. Some people call it an imperfect bulb. I cannot see its imperfection, so I call it a bulb as it works very well. True, it has no basal plate, but having the rhizomatous rootstock serves its purpose as it does not require an organ of perennuation. When a leaf is generated it is very small and only partially formed. As these leaves are formed the rhizomatous rootstock, which is the woody part where the roots come out, elongates. You will probably tell me rubbish, the clivia miniata stays the same length, it is the caulescens that elongates. But take your miniata out of the ground, clean it off and examine the rhizomatous rootstock carefully. Underneath you will see there is an area where attrition occurs, and it almost seems as if termites were gnawing the base off. I don't pretend to know what gnaws it off, but something does as the rhizome pulls itself into the ground with its new roots. This is quite common with bulbs and easily seen with the gladiolus. When new roots form they do not form at the bottom, but at the top of the rootstock.

Now a plant has several methods of growth. By growth I mean getting bigger. Firstly a miniature organ is formed, what is known as a primordium. Then, when the time is ripe this organ is pumped up much as a football bladder. Each cell is enlarged as much as ten times or more. Another method is somatic division of cells. Somatic means of the body without the germ cells. This is the normal growth division where one cell will split into two diploid cells. These cells are also known as meristem cells and are not found in certain parts of the plant. We are dealing with a monocot, and monocots have meristem tissue in the apical meristem, in the rhizomatous rootstock below the apical growth point, at the root tips, and also at certain positions on the root where a secondary root may branch off. There are also meristem cells in the leaf, both in the cuticle and in the mesophyll. In other words, without meristem there can be no new growth, no new cells are formed.

OK for now. Let me know if this is simple and plain enough. If anyone disagrees with what I have said, let him or her be heard. I am a human, and fragile and fallible. I welcome corrections.

Then if you wish to go on we can get into cells and variegation. It is up to you.