Clive Innes is reputed to
have said 'You just break a piece off and it will grow' and this is certainly true for most
succulents such as Schlumbergeras, Rhipsalidopsis, and the like. One grower does that and
puts the piece in a glass of water, and it roots!. But let them develop a callus first.
Cactus offsets don't root quite so readily but most will if not stressed. Sometimes, when
a cactus dies off over winter it is often possible to rescue parts of it and pot these up.
When a tall-growing cacti, such as a cerei, becomes too tall, or untidy
at its base, the top can be re-rooted. That top (the scion) is cut off
with a very sharp knife to be re-rooted and grown on. It is advisable
to bevel the edge of the scion base and remove any areoles. These might
otherwise root and spoil the symmetry of the new plant. The cut surface
should be allowed to dry, or callus, even for weeks in the case of a large
cutting. It should be placed in the shade and upright to avoid it developing
a bend. It should not be in contact with any soil or moisture at this
time. Quite often, the cutting will put out new roots during this drying
off period. The old stem-plant may, itself, put out new side-shoots from
the top-most areoles and may be re-rooted eventually.
Some plants which are sensitive to excessive moisture in the soil, or
are slow-growing, or otherwise difficult to cultivate, can benefit from
being grafted on to a faster-growing, more vigorous root-stock. Popular
at one time was to graft a Schlumbergera or Rhipsalidopsis to
produce what can become a very impressive 'standard'. Some suitable root-stocks
are - Cereus such as Cereus jamacaru or C. peruvianus,
Trichocereus pachanoi and T. bridgesii, or
Eriocereus jusbertii for example, and many more.
Grafting is similar to what was done above in 'Cuttings'. The top, or
scion, is cut off with that very sharp knife, and the root-stock similarly
prepared. But now one must act quickly to unite the scion and base as
quickly as possible to avoid any drying off. Care must be taken not to
introduce any dirt or air-bubbles between the two surfaces.
As before, the graft should be put in the shade, not watered or sprayed,
and after a few days watered from the below. It is usually necessary to
support the new graft in some way, and to ensure the two surfaces remain
in very close contact. This is usually done by the careful use of elastic
bands. Grafting is best carried out when plants are growing vigorously
as in summertime. See Teesside Branch for interesting information.