Among the species of Orthophytum, one of the largest recognizable groups is Orthophytum subcomplex disjunctum. To oversimplify, these are the species that produce elongate inflorescences with specialized flower-bearing structures that look somewhat like small cones with their tightly spiraled, thick, stiff, usually recurved floral bracts (Fig. 1). These cones are always formed at the top of the aboveground stem, and in many cases they also appear as axillary branches from leaf-like structures that are technically primary bracts. With many species in the complex, it is common for offsets to be produced at the apex of both the lateral and terminal cones.

Among bromeliads, the resumption of vegetative growth at the tip of a fully differentiated inflorescence branch appears in some species of Orthophytum and most species/cultivars of Ananus. In a broader view, this resumption of vegetative growth from a fully developed inflorescences is quite rare.

When vegetative offsets are produced from these cones of the disjunctum subcomplex, they provide an easy method for propagating the species as long as you follow a few simple rules, based on the growth pattern of species within this subcomplex.

One important thing to realize is that plant growth in the disjunctum subcomplex takes place in two separate phases. In the first phase, the stem is typically buried under the soil, produces roots and closely spaced leaves that (when present) form die basal rosette. Basal vegetative offsets are produced from buds in the leaf axils during this phase of growth. Depending upon the species involved, these basal offsets may appear early in die growth of the plant and show up long before the first open flowers are produced (O. conquistense is a most dramatic example of this). In other species, such as 0. horridum, basal offsets often do not appear until much later in die growth cycle. This structure is morphologically the true 'stem' in the disjunctum subcomplex, but there is such a long history of confusion in the naming of the structures produced during die two phases of growth diat I will refer to this by the more descriptive term: underground stem'. Later on, it will become clear diat an underground stem' is not always underground.

A second phase of growth starts once the 'underground stem' reaches sufficient size, and begins to form a single 'above-ground stem' (Fig. 2) that is usually smaller in diameter than the underground stem and frequently tapers as it elongates. This above-ground stem never produces roots, usually elongates rapidly with widely separated nodes, never produces offsets in the leaf/bract axils, and produces the flower-bearing cones. Another distinction that is not evident most of the time is that the above-ground stem has a much more limited life span than the underground stem. Once the flowers have all bloomed on an above-ground stem, it starts to die. Once the above-ground stems have turned brown and shriveled, you can see the still live tops of the underground stems they were attached to, at ground level (Fig. 3). The rate of death may...