I have been asked by Kenny to write an article for his Web Site and I have chosen to do so on hybridising. Hybridising is becoming more popular with amateur growers and some excellent hybrids are being produced, both for the Show-bench and general cultivation but initially it can be fun just producing a few blooms for your garden, to sell or just give away. Whatever stage you are at with regard to this aspect of growing begonias do not be put off by people telling you that it is too difficult or that you need to grow the resulting seed over the coldest winter months with heat and under lights, this is not necessarily so. However before we start I would like to address a few basic rules without getting too technical which, by keeping them in mind will help you better understand the results that you achieve. Rule One: The characteristics of the parent that you use may be either Dominant or Recessive. That will apply whenever you cross a species begonia. A species begonia will produce an identical begonia when crossed with itself. For example, when crossing a tall species with a compact species, one of those characteristics may be dominant and the other recessive. The first offspring of that cross (F1) will show dominant characteristics. You might be looking for the recessive characteristics in which case you would cross the offspring with itself or with each other. That gives the (F2) generation. Those offspring will show a ratio of about three with dominant to one with recessive in that particular characteristic. The same rule applies to other characteristics such as leaves, flowers and so on, so you should understand that the result that you desire may require several crosses of the (F1) offspring with each other or with themselves. You may also need to cross the (F1) offspring with one or both parents. This is known as �Backcrossing� and is a handy tool to use. Rule Two: When crossing a hybrid with itself, you will never get offspring that are identical to the hybrid. F2 hybrids are obtained by crossing two F1 hybrids and unless you can duplicate those you have little chance of success. When hybridising tuberhybrida you are working with the results of many years� crosses and backcrosses involving dozens of parents and grandparents. This is both an advantage and a disadvantage. The advantage is that you have a large gene pool that can give some spectacular results. The disadvantage is that it is not easy to identify the dominant and the recessive characteristics. The big problem in working with tuberhybrida is that the largest and best blooms are completely double and almost never show any pollen. Some are always sterile. Having dealt with some of the theory we now come to the practical aspects of breeding begonias. Unlike some many other plants begonias have separate male and female flowers on the same stem in the form of three flowers, a centre male bloom flanked by two females, which have a triangular shaped seedpod immediately behind their petals. On occasions one of these females may in fact be another male. When hybridising specie begonias and many of the multiflora types such as �Le Flamboyant� the process is simple as the male flowers are single with a plentiful supply of pollen on the centrally located stamens. With better quality large flowered double tuberhybrida however things are different as over many many years of selective breeding these central stamens have become petals. This of course poses a problem for the would be hybridiser. Pollen can usually be found in inferior flowers but of course the use of inferior stock will not help one�s cause to produce a better bloom. Therefore we have to hunt pollen so where can we find it? There are some varieties that will give pollen but this usually does not occur until the latter part of the season, when flowers tend to get smaller and often distorted. In these cases the centre of the flower is often replaced by pollen bearing stamens, some times just one or two, or rogue stamens, which appear among the petals of the flower. Pollen is generally easier to find among hanging baskets as the flowers age and become fully open. Another way to ensure a supply of pollen is to take early cuttings from selected plants and to grow them under harsh conditions by keeping them dry and deprived of nutrients. In such cases the small plants goes into self-preservation mode and produce distorted stamen bearing flowers. A further method, which assists in producing pollen-bearing flowers, is to place the cuttings mentioned above in a totally dark environment for at least 14 hours per day, the Black Out Treatment. The plants should be kept slightly dry and under fed and any buds present at the start should be removed, as these are unlikely to produce pollen. Pollination There are a number of ways to achieve pollination but here we will deal with just two. No matter which option you choose it should be done on a warm day in order that the �ripe� pollen adheres readily to the stigmas on the female flower, thus ensuring that fertilisation takes place. One thing to remember is to choose female flowers that have short stigmas, as flowers with long ones tend not to be as receptive. As insurance it is good policy to repeat the same transfer of pollen a day or so later. Method One For this you will need a small soft haired artist�s brush, preferably Sable. The next step is to find a male flower with pollen. To check if the pollen is ripe gently tap the stem just behind the flower, if ripe you will notice a yellow powder fall onto the petals. This powder (pollen) can then be picked up on the hairs of the brush and transferred to the stigma of the female flower. To ensure a good �take� the process can be repeated more than once. The brush should be washed and dried between pollinations of differing varieties or a number of different brushes used. A good tip is to wash the brush in Methylated Spirits as it dries very quickly. It is also essential that the female is receptive. The stigmas on a newly opened female flower will be green in colour and gradually over a few days turning gold. It is at this point when they are most likely to be receptive. This can be checked by using a good magnifying glass. If the stigmas have globules of nectar on their fine hairs they will receive the pollen well. Trying to put pollen onto the stigmas when to female is not receptive will result in damage to these hairs. Once the pollen has been transferred a small label should be tied to the stem of the female flower. It should record the name of the pollen parent and the female recipient plus the date.

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