The Editor's Tutorial |
.Propagation |
 |
Propagation is an important part of the seasonal cycle. Tuberous
begonias do not not grow true from seed, so the only way to increase
identical stock is by taking cuttings. (Tissue culture was tried for
several years but was never really successful).
Cuttings can be taken either directly
from the tuber in the form of surplus stems (basal cuttings), or as side shoots of the main
stem (stem cuttings). The earlier in the season they are taken the longer they have to
develop worthwhile sized tubers.
It must be remembered that the aim
is to produce a tuber and not a flowering plant, for this reason the
growing tip is pinched out once the cutting has rooted and the plant restricted to a relatively small pot. |
Fred
Martin |
. |
 |
This is what we are out to achieve, large
plump tubers that will give worthwhile results the following season.
Do not be concerned that the shape may
be irregular, unlike tubers produced from seed those developed from
cuttings will often appear somewhat misshapen. |
. |
 |
The compost I am using is SCOTTS Levington
F2 premixed with sufficient water to make it cling together. |
. |
 |
Additional water, then silver sand is poured
into a hole in the centre of the compost of each 3½" 9cm pot. I believe that the sand
encourages root action and helps tuber development. |
. |
 |
This is a newly acquired variety,
to build up stocks I am going to take off as many cuttings
as possible this year. The strongest stem will be left and the
others removed for basal cuttings when about 4" 10cm. in height. Later
in the season as many stem cuttings as possible will also be taken. |
. |
 |
Basal
Cuttings are taken straight off the tuber
and may well produce the best new stock for next year because they can be taken
early in the season. They can be removed with a sharp knife
but I find it easier to just pull them free. With any luck a few
roots will also be included. The wound on the tuber is dressed
with a little green sulphur and left uncovered for a few days. |
. |
 |
Stem Cuttings these are really
potential flowering side shoots and removing them will affect the final
appearance of the plant, I would suggest however that priority is given
to build up stocks of any newly acquired variety. The shoots form at the
base of a leaf axis. |
. |
 |
Take care not to cut into the main stem or
leaf but to include the eye which is
protected by a bract. The knife, or better still scalpel, is
dipped in methylated spirits after each cut to sterilize the blade. |
. |
 |
Once the cutting has been severed it is potted
individually in a 3½" 9cm pot, rooting powder is not necessary. |
. |
 |
After about 4 weeks in a heated
propagator placed in a well shaded spot (under the staging is ideal) the cuttings
should be rooted and the propagator top can be removed. During this whole
period it is necessary to inspect regularly as any rotting leaves will quickly spread
through the whole tray.
After a few more weeks the cuttings will be
ready for potting on. I use Levington M3 which is stronger than
the F2 used to strike them in. The growing tips are pinched out and all
buds removed. |
. |
 |
A
large plant can be grown from early cuttings, but this is not the aim, the
idea is to produce a worthwhile tuber for the following season and for
this reason the developing plant should be restricted to a relatively
small pot.
Towards the end of the season my cuttings are placed into a
heated sandbed, on top of the sharp sand is a layer of soil less compost and
the pots are partially buried into this. A soil temperature of 55ºf. 12ºc is
set. This will keep the plants in green leaf until about late
November. During this time watering is maintained. |
. |
In 1971 I purchased Melissa from Blackmore & Langdon and the
following year Roy Hartley from T.White & Son.
I am
still growing both these varieties today and my present stock originates
from these two tubers bought over thirty years ago. Goodness only knows
how many cuttings have been taken in that time .
Named varieties are not cheap, but when you consider the pleasure and
value that I have received during that time then the price becomes
less of a purchase and more of an investment.
The moral to this story is when you obtain a
new variety KEEP IT, take cuttings.
|
. |
|
|
|