v

LATE AUTUMN CULTURE

.

 

  •  Cymbidiums can be grown without supplementary heat in winter in this country, and in many temperate locations. Ideally plants should be brought into a porch or glasshouse, but can remain outside if covered, for example, by a sheet of plastic to divert the worst of the rain. Plants not in flower can withstand low temperatures, even down to freezing, although should be dept above 5o celsius if possible Flower are much more vulnerable to low temperatures, and plants in spike should not be allowed to fall to these low temperatures if possible.
  • If it is anticipated that the plants will be exposed to low temperatures during the winter months, then it is generally desirable to utilise a coarser growing medium, one that allows most of the water to drain away and which can be dept fairly dry during the coldest of conditions. If a plants roots are kept wet be a tight mix during cold conditions, growing difficulties are likely to be experienced. In particular cold and wet conditions will often result in the death of the roots, which can have serious a impact on subsequent growth and flowering.

  • To obtain the maximum growth of young plants, they should be maintained at higher temperatures, say above 10o celsius. Should young plants receive a set-back over the winter, this can retard the date of their eventual flowering considerably. Once they experience a check it can be quite some time before their growth can be brought up to a satisfactory level again. The provision of bottom heat at this time of the year will considerably increase the growth of small mericlones, seedlings and back bulb propagations.

  • At this time of the year, with vegetative growth at a low level, the frequency of watering should be reduced. If relatively warm growing conditions can be maintained, then watering once every seven to ten days will be adequate. If an unheated growing area is maintained, then the plants should be kept relatively dry.If wet and cold conditions are maintained at the plants roots, root death can occur, which will reduce subsequent growth and flower production. The plants which have the warmer growing species in their breeding, such as some of the asiatic miniature species, and standards such as Cym. erythrostylum and insigne will be more prone to damage under such conditions, and should therefore be kept warmer and dryer. Root damage is often revealed by the loss of flowers at the end of the spikes, the plant being unable to support all the developing flowers where appreciable root damage has occurred.

  • Some orchid flowers can be disfigured if water is allowed to remain on them during cooler weather. All watering must be completed during the winter with care, some clones in particular being easily damaged if caution is not exercised.

  • Fertiliser can be reduced in line with generally reduced plant activity. With cooler conditions, use inorganic fertiliser as organic material require biological activity to make the elements available, such activity being very efficient under warm conditions such as those experienced during summer.

  • In the autumn plants should be gradually exposed to increased levels of light, receiving full light by mid-autumn. This ensures the pseudobulbs are fully mature of he subsequent flowering. Any increased light should be given gradually to reduce the risk of burning of the foliage.

  • Spike management is important at this time of the year. The page on spike management should be noted.

  • Those who have glasshouses should check that they are in good condition for the winter, and that they are waterproof, with heating - if available - working properly. Remember, in a glasshouse, when night comes and temperatures fall, humidity will increase, and often condensation on the structure and plants can occur. With cold and damp, flower spotting and similar conditions can occur. Good ventilation and air movement can diminish these difficulties. The running of a fan, especially at night, assists in maintaining good plant health

  • Remember we have shows coming up. Think about preparing your plants now for display by cleaning them up, and by ensuring the best production and display possible.

  • Many plants will have showed, or are showing, yellowing and loss of leaves, especially from the back pseudobulbs. This is part of the annual growth pattern, and is nothing to become concerned about. If there is a wider loss of foliage, however, have a good look at the plants roots and assess your watering. Over watering at th is time of the year can be a serious problem - it may just be a leak in the roof that requires attention.

 

 


Site established 9th May 1998