how to divide cymbidium orchids
It is best not to divide a Cymbidium as dividing causes the plant considerable stress because, when dividing, the potting soil must be disturbed and this generally damages the roots.
If a plant must be divided, try and divide the plant into pieces consisting of at least 3 or 4 bulbs. A good plant will generally produce flower spikes the season following division. As a rule of thumb it will probably produce half the number of spikes that it would have produced if it had been left undivided.
There are only three reasons for dividing a cymbidium:
1. If the plant has become too big and you wish to reduce the size of the plant.
2. If you wish to have more than one piece of that plant, for example if you wish to sell a piece or perhaps you want to have one piece for exhibition and one piece to breed with.
3. If the plant has become untidy due to poor culture with dead bulbs in the centre it is necessary to divide the plant to remove the bulbs.
when to divide
A plant is best divided as soon as it has finished flowering. If the plant has not flowered for some reason, divide the plant during the winter months. When dividing plants, work out how the plant grew. Bear in the mind that the backbulbs are the oldest part of the plant from which other parts have grown and generally removing a backbulb will cause a plant to fall into 2 or more pieces.
After you have divided a plant, sell or give away the pieces that you do not require. Because a plant generally doubles in size every year, unless you have unlimited space the production of flowers from your collection will be reduced as the plants become more crowded. If you are not exactly sure where to cut the plant to divide it, a good guide is to simply cut the backbulbs in halves and then pull the plant apart.
After dividing a plant, reduce the length of the leaves by one third on the older bulbs in order to reduce transpiration from the leaves which will lead to bulb shrivel on a newly divided plant. Place the plant in heavy shade for 4 weeks.