|Fall cutting from an oca plant that formed tubers|
Notice that the main stem has died and that it
has formed no roots.
The cuttings that we took from plants that had formed tubers are the more interesting case. Until recently, they looked as healthy as the other group of cuttings and they continued to grow indoors through the winter. About a month ago, I noticed that many of them were forming aerial tubers. The new growth branches began to thicken. Over the past couple of weeks, it has become obvious that the old stems are dying. On pulling them from the soil, the cause is clear: none of them formed roots.
The division between the two groups is very clear. Every cutting from the plants that had not formed tubers has well developed roots. Every cutting from the plants that had formed tubers has no roots. In addition, the stumps of the original plants, which obviously had roots, died back as well. So, it is not just a failure to form new roots; the roots on the original plants appear to die off after tuber formation.
|The new growth thickens into aerial tubers|
These can be plucked from the dying stem or
will eventually fall off on their own.
Each can be planted and forms a new plant.
This is an important consideration for the oca propagator. Plants can probably be continued from cuttings indefinitely as long as the plant is not allowed to form tubers. Cuttings taken from a plant that has formed tubers will be an intermediate step toward the production of sprouted aerial tubers which can be separated and replanted.