A cactus expected to grow round becomes a rippling band. Another forms a low mass that seems to spread like moss. At the 13th Omoshiro Cactus Competition, opening at Izu Shaboten Zoo on 10 October, two Mammillaria specimens depart from the familiar outline in different ways. Rather than passing them as curiosities, it is worth asking where the direction of growth changed.
Begin with the round form
The operator’s official announcement says the show presents ten plants selected from the zoo’s collection. One is Shikishima cristata, a plant whose ordinary rounded growth has developed a band-like growing point and folded into something like a length of ribbon. In the official photograph, bright green ribs rise from the centre of the pot and continue as a chain of waves. It is more than an isolated curiosity: beside the ordinary form, it becomes a record of how far an outline can change.
Mammillaria bocasana ‘Fred’ is labelled sekka—monstrose growth—in the same announcement. The usual Takasago form is a rounded cactus wrapped in white spines, while ‘Fred’ gathers small glossy green masses and spreads close to the surface. The cristate plant repeats a band; ‘Fred’ appears as a cluster whose centre is harder to read.
Calling both simply “strange cacti” reduces the difference to spectacle. Hold the normal form in mind and ask whether roundness became a band or loosened into many small masses. Shape then becomes more than ornament: it becomes a record of growth. A collection is not only an accumulation of names. It can preserve different passages of time from a similar rounded beginning and place them close enough to compare.
When a point lengthens into a band
University of Wisconsin–Madison Extension explains that normal growth in the apical meristem is concentrated at one point, producing an essentially cylindrical axis. In fasciation, that growing point elongates sideways and creates flattened, ribbon-like or fan-shaped tissue. In cacti, the band may curve and fold as it continues, producing contours often compared with the ridges of a brain. Thinking of an upward point replaced by a long edge makes clear that the wave is not a surface pattern; it is the shape of the growing region itself.
In the photograph of Shikishima, the key is not the impression of several stems splitting apart, but the lengthening of the growing edge itself. Ribs and areoles continue across the band, while its upper margin bends instead of extending in one direction. Following those lines from the base of the pot to the crest brings the mechanism closer than the dramatic silhouette alone.
The cause of this particular plant cannot be diagnosed from a photograph. The RHS lists several possible triggers for fasciation, including genetic change, microorganisms, frost, insects and mechanical injury, while noting that many cases remain unexplained. Wisconsin Extension also notes that unusual forms may be maintained by vegetative propagation and collected, while some plants can produce a return to normal growth. A display label helps us read the form; it is not permission to assign the same cause to an undocumented plant.
Look three times before voting
At the display, begin with the outer contour of the whole plant. Then lower your gaze to the point where a band or small masses rise from the pot. Finally, move closer and follow the directions of the areoles and spines. Moving among those three distances keeps the broad wave of cristate growth distinct from the fine repetition of ‘Fred’. Folds that overlap in a flat photograph also reveal depth, shadow and the thickness of the band in person; that difference is a reason to see the plant rather than only its image.
The show runs through 23 November in the Fifth Greenhouse’s Mexico section. Visitors can vote for a favourite among the ten plants, and an official social-media broadcast with commentary from the zoo’s cactus specialist is planned. Check the official site for current park hours and visiting conditions before travelling.
A vote need not be a choice of the most bizarre silhouette. Remember the ordinary form, trace the outline, imagine the altered growing point, then return to the same pot. That movement turns a “rare oddity” back into an individual plant that has spent time making its shape.