The Editor's Tutorial

.Starting from Seed

   An amazing feat of nature - to produce a full grown begonia from a tiny seed in just six months.
  Whether you have purchased the seed or obtained it by hybridisation, to grow plants by starting from seed requires a certain amount of care and certainly a delicate touch when it comes to transplanting.
  Unfortunately the very conditions that are necessary for starting are also an ideal environment for  fungal disease.

Carol Wilkins of Ballaarat

Begonia seed is minute, like pepper dust, shown here are 1,000.
Blackmore & Langdon supply packets of hand pollinated seed that produces excellent results of tuberous double begonias in mixed and separate colours.  

The compost that I am using is Scotts Levington Professional F1 (soilless), very lightly firmed and the surface levelled.  Once the seed is sown it will not be covered.
Water is soaked up from below in a bowl of tepid water until the surface of the compost has become moist. To achieve this without saturating the compost it may be necessary to dunk the tray more than once just for about a minute each time.

Because the seed is so small it can be difficult to spread evenly I mix a little dry silver sand to make distribution easier.  The mixture is spread from a sheet of writing paper which is gently tapped on the underside.  Once sown the seed is not covered.

The trays are placed in a heated propagator allowing some light to enter, but not direct sunlight.  A temperature of 70°f. 21°c. is ideal.  I find it convenient to place the propagator in the kitchen, (courtesy of a tolerant wife). Electric propagators are invariably low powered and often unable to cope with the chill of an unheated greenhouse on a cold night.  It does not seem economic to heat an otherwise empty greenhouse in late January.  

The compost must be kept moist, damp capillary matting under the trays ensures good humidity and a fine spray over the surface nourishes the developing seed.  .
This picture is eight days after sowing.  The centre tray (semperflorens) is already showing good germination.  Left and right hand trays (non-stop) are just beginning.  

Once germination has taken place more light is required and after about five weeks the young seedlings are ready to be thinned.  As this stage approaches the propagator tops can be removed during the day to acclimatise the seedlings prior to transplanting.  

The seedlings are best transplanted into fresh compost as soon as is practical, that is as soon as the first leaves are properly formed.  Great care is needed for this delicate operation.
The coin is a 5p. piece, 18mm across.

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