The National Begonia Society


The Champion's Diary  2007
A Year with Begonias

John Chiswell
National Cut-bloom Champion 2006

   I live in Midsomer Norton, North Somerset, which lies in the mendip hills in the south west of England.

   I have been growing and showing begonias for 9 years. Prior to that I grew chrysantheums for 22 years, where I became the national champion for large early chrysantheums 4 times, and won the Bentley trophy for ‘best exhibit’ in the national show twice.

   Following redundancy from my office job in shoe manufacturing some 10 years ago I started my own business selling hanging baskets which meant I no longer had room for the chrysanthemums. I hang my baskets in a 25’ x 50’ nethouse prior to delivery which fortunately leaves room in my greenhouses for the begonias from the middle of May.

   In the 9 years I have been showing begonias at the National Show I have been 3rd,4th,2nd and finally last year I came 1st. This was due to my having produced the best flowers I have ever grown, in a season where it had been difficult for most people with the weather we had. I hope to build on the success of last year and look forward to competing in the nationals again.

   Thanks to the national-begonia website you will be able to follow my year with begonias up to and during the National Show with regular updates and pictures. Fingers crossed for another good year!

   What a summer! Sorry, non summer!
   What with the rain and low night temperatures, down to 5ºC at night, at the end of June and early July. Here we are last week of July and I still haven’t got any flower on my runner beans.

   I have moved most of my begonia’s intended for the national back into the greenhouses and covered those left in the net-house with corolux sheet to keep the rain off.

   The timing of flowers for the national differs by variety but in general most take 35 days from buds the size of a 50p piece to fully out with me. Some varieties, i.e. Powder Puff and Mandalay, take 30-32 days and others such as Roy Hartley and Tom Brownlee take 40-42 days. Timing is something that you can only learn with experience and is unique to your own personal situation.

   I remove all buds, 50p size and above, 7 weeks from the show. At 5 weeks from the show I select the bud that will be allowed to flower. Using 50p size as a benchmark, I leave larger buds for the varieties that take longer than 35 days and smaller buds for those varieties that take less.

   A feed is given of mono ammonium phosphate, 1oz to 4gallon of water, 4 weeks prior to show. Approximately 1 week later, the buds are protected from damage by using 8” polystyrene plates and cotton wool. The plates have a slit cut in them as shown in the first picture below.

   I buy cheap pillows for cotton wool as they contain synthetic wool which does not cling to leaves or buds as natural cotton wool would.

   All plants have another feed of mono ammonium phosphate 2 weeks from the show.

   Hopefully I shall have some quality blooms for the National Show at Kingsheath, Birmingham on the 1st & 2nd.September.

Plates to protect blooms.


Blooms for the Portchester Show.

Plants for the National Show.


Begonias in the net house.




   When begonia pots are full of roots, that is roots just reaching the bottom of the pot NOT potbound, they are moved into final pots for flowering.  They are potted on two sizes up, 4" into 6", 5" into 7", and so on.
  The final mix is 5 parts soil from stack, 3 parts Vapagrow Container, 1 part Perlite, 1 part Vermiculite, and 1 part shredded beach leaves.  To each 8 gallons of mix, 6 ounces of John Innes Base and 1 ounce of trace element frit are added.
  Begonias final potted before the end of May are allowed to flower for the Portchester Show  on the 4th.& 5th. August.  Begonias that are final potted in in June are flowered for the National Show on 1st. & 2nd. September.  Any pots not full of root by the end of June are just grown for tuber.

  Cuttings rooted in March and up to mid April are now in 4" pots and should be ready for final potting by mid June.  Two thirds of the flowers taken to the National last year were from similar early rooted cuttings.

  The key to good plants and then ultimately good flowers is control of the watering can.  Do not water until the pot is completely dry.  If in doubt leave another day, but when water is given it must be sufficient to completely soak the pot contents.


Cuttings ready for 4"potting.

This year's seedling ready for 4" potting.

Plant ready for final potting.

Cuttings on the hotbed.



  Now we are approaching the time when we are going to move the tubers and cutting tubers into their first pots.

  When the cutting tubers are about 2 inches high they are potted on in 3½ inch pots.  The compost mix I use in my pots is 2 parts soil, 4 parts Vapagrow Container, 1 part Vermiculite and 1 part Perlite.  The reason for a higher amount of peat than would be the norm is that cutting tubers need to be weened  from the peat mix of the hotbed before they are able to flourish in the John Innes type mix.

  The larger tubers are moved from the hotbed when the shoots are about an inch high, if they are left  on any longer the root ball will be too large for the ideal sized pot.  The pot size to use is the smallest that the root ball will comfortably fit into, this is usually about 5 inches, but some of mine can be as large as 7 inches.  The compost mix I use on these larger tubers is 4 parts soil, 4 parts Vapagrow Container, 1 part Vermiculite and 1 part Perlite with 4 ounces of John Innes base to every 8 gallons of mix.  These larger tubers are more vigorous and are able to cope with the higher proportion of soil to peat.

  I have changed to Vapagrow Container instead of my usual peat because I have had problems with old stock which has gone sour, and Vapagrow has the date of packing marked on the bag therefore giving you the confidence of its freshness.  Vapagrow do various grades of compost with the container type being a favourite of mine with its coarseness giving a nice open mix.

  As soon as the weather is dry enough I will be making my soil stack for 2008.  My local garden centre saves all unsold turf for me which I buy at a fraction of its normal cost.  It is good quality red Mendip loam, I even know the field it has been cut from!  The soil stack is made from layers of 12 rolls of turf covered with 2 bags of well rotted cow manure and 1 bag of Beech leaves.  The stack is made 4 layers high and prior to its use the soil is broken up with a rotavator.

Larger tubers on the hotbed.

Cutting and larger tubers in pots.

Soil stack.

Rotavated soil stack.



  All tubers and cutting tubers are started in 4 parts irish moss peat, 1 part perlite and 1 part vermiculite. Small cutting tubers are started in cell trays and are moved to the hotbed as soon as a shoot appears.

   The main hotbed is 8’ by 6’ with a 300watt heating cable set to give 25ºC around the tubers. The hotbed is lined with polythene and filled 3” deep with the peat mixture. 2x 400watt sodium halide lamps are suspended about 4’ above the hotbed and are on from 06.00hrs until 20.00hrs every day. 

   Cuttings rooted prior to September last year were left with no water from the end of November to die back in their original pots until the beginning of January when the small tubers were transplanted into the cell trays and put on a probagater. When they start to shoot they are taken from the cells and moved to the hotbed. 

   Cuttings rooted in September and October were left growing until the middle of January and then had their leaves removed. By the end of January most of the compost was removed from these plants, their roots were trimmed and they were put straight onto the hotbed. 

   Last years flowering plants had been kept growing until the end of November at which time water was withheld. The tubers were finally removed from their pots early January and were put on the hotbed in the 2nd week of February. These tubers will be flowered for the Portchester Show at the beginning of August providing the hot weather doesn’t ruin them as happened last year!

   The cutting tubers and any early cuttings rooted from the larger tubers that produce multiple shoots will be flowered for the National early September. All the flowers I showed at the National were from this selection of plants.

View of the hotbed.

Stage at which cutting tubers are moved to the hotbed.

Close-up of late rooted cuttings on hotbed.

Cutting tubers in cell trays.