Twin-scaling success!

This month in the Propagation Department we are busy twin-scaling – which is a clever technique to quickly propagate bulbs that are otherwise slow to increase

This blog will give you a quick step-by-step guide of how to twin-scale and what materials to use. It is really easy once you know how, and you may be able to create up to 40 twin-scales from a large bulb.
Nerines, hyacinths and daffodils can all be twin-scaled as the scales in these bulbs are tightly packed; unlike, for example, fritillaries and lilies which have looser scales.
Twin scalingFirst we waited till the nerine had finished flowering and the bulb had gone dormant. Once we had sterilised our cutting board, we peeled off aged parts of the outer skin with a sterilised knife.
Now for the delicate bit. We cut the bulb into segments and detached two scales joined by the basal plate, starting with the outer scales using a sharp, clean knife.

Potting, not rotting

Twin scalingThen we placed the scales along with a little fungicidal powder in a clear plastic bag and gently shook the bag so the scales were covered in the powder and therefore less likely to rot.

Following this we put the twin scales and some vermiculite into another clear plastic bag (see left), inflated and sealed the bag with string and, importantly, added a label.
The twin-scales are now ready: the bag was placed in a dark cupboard at 20ºC (68ºF). You could use an airing cupboard at home. We check the bag containing twin-scales regularly to see if rot has affected any of them.
After 12 weeks, the fun begins; bulblets (mini bulbs) should have appeared on the basal plate. Gently remove any soft scales, but leave firm ones and pot up your new plant in a compost consisting of 50% loam-based potting compost and 50% grit for good drainage; finally, add grit on the surface. Water and label each pot with the plant name - and I find a date is always useful, too.
In summer, place the plant in a cool, shaded environment and in the winter a cold frame is ideal. Each spring or autumn the plants may need potting on if root bound.

The plants are ready for the garden when they reach flowering size in about three years or so.



Nerine bowdeniiTips for success

  1. The basal plate must be attached to both scales

  2. Ensure good hygiene of tools and twin-scales.

  3. Keep compost moist; not too dry or wet.

  4. Ensure warmth and good aeration.


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