growing orchids successfully - a beginners guide....
Generally, to grow orchids successfully, you have to try to reproduce the conditions in which the plant is used to in nature, hybrids are more adaptable than their parents, and will tolerate conditions which are to some degree either side of those best suited to their parents.
Orchids adapt to one of three zones or temperature bands, relative to where they grow, remember, that whilst an orchid may come from a warm country, it may well grow at a high elevation, and needs a temperature lower than that which would normally associate with that part of the world. These zones are referred to as cool, intermediate and warm, with normally a temperature drop at night.
The bands can be defined generally as follows:-
Cool growing.......48/55 deg f. winter overnight......55/70 deg f. summer day...........40/60% humidity Intermediate .......58/62 deg f. winter overnight......85/90 deg f. summer day........... 45/65% humidity.
Warm...................65/70 deg f. winter overnight......90/95 deg f. summer day............50/75% plus.
An idea of which temperature band the orchid belongs to may be gleaned from the leaves, cool growing plants by and large have thin leaves, whilst those used to much warmth have thick fleshy ones, there are of course as always exceptions to this rule, so be wary.
A good maxim for suitable conditions would be:- More heat + more light = more shade, more air, more humidity, more water. Less heat and light= less air, less shade, less humidity, less water.
Of course in addition to providing a climate in which they will be happy, the amount of sunlight which falls onto the plant must also be considered, in general terms, most orchids need shade from direct sunlight, and good air movement, just as we would if we had to stand in one place for all of our life!
Shading of at least 60% will be needed during the Spring and Summer, possibly even into Autumn if the weather is clear and warm and of course all year round in the tropics. To much light results in sunburned leaves or at least yellow (or dark red) and skinny foliage, not enough light and the result is dark green foliage and no flowers.
POTTING MIXES AND WATERING
See also our potting demonstration page
Before considering what the orchid books tell us about potting mixes, and watering, consider what will suit your needs also, if you are always around to water frequently, as and when the mix begins to dry out. a very open mix will demand during a hot period of weather, then regular watering is O.K. but if you cannot devote a daily regime of care, then perhaps a more water retentive medium may be better for the plants you are growing.
Most vandaceous orchids, some Phaleanopsis, and some Dendrobiums can be grown quite easily in wooden slatted baskets, without any compost at all, but obviously, this culture demands daily waterings.
Cymbidiums, and Cattleya varieties do well in a mix of bark chippings, mixed with a little perlite, and charcoal to keep it sweet.
Dendrobiums, Oncidiums, Odontoglossums, Catasetums, and many other species will also be happy in this mix, but when deciding whether or not to use a large, medium or small variety of bark chippings, consider the thickness of the roots, if they are thick, then the largest chippings will suit, if they are thin then a fine mix would be best.
Paphiopedilums and Phragmipediums seem to do better in a mix of rockwool, bark foam and a little sphagnum moss with some perlite, (or at least they do for us), and a pinch of dolomite lime does not go amiss with some of the Chinese species.
When watering, try always to use rainwater or that produced by a reverse osmosis system unless you are very sure about the quality of your towns water supply; having remembered to use the potting mix which suits your availability as well as the need of the plant, you should water when the plant has almost dried out, and the mix is just slightly damp, this means inside the pot, not on the surface, so if in doubt use a wooden stick to test for moisture, stick it into the mix, and if t here is water present, and the stick has darkened considerably, then perhaps the time to water has not arrived.
In most cases during the summer months watering would take place every 4/5 days here in the UK and perhaps only every 10/14 days in winter, or even longer. Always flush the pot through to get rid of any excess salts which may have built up in the medium due to feeding.
FEEDING Orchids are notoriously week feeders, and a solution of one quarter to half strength fertiliser is all most plants will need, a balanced 30/20/20 is best for plants potted in a bark mix, as the bark will neutralise the nitrogen, and a well balanced 20/20/20 mix for most others.
AFTER FLOWERING Remove any dead flowers and old flowers and sheaths, but take care not to damage the pseudobulb from which the inflorescence grew; in the case of Phalaenopsis, the flower spike would have grown from between the leaves on the plant body, it should be cut back to within an inch of where it appeared, or if you wish to flower the plant sooner, and the flower spike is still alive (perhaps an odd flower left on it) then look for a small node or bump below where the first flower appeared along it and trim just above there, if you are in luck it will produce a new spike from there and flower more quickly.
GROWING IN THE HOME ? If you want orchid plants delivered by post there are many links on our website where you can buy either cut flowers or orchid plants suitable for indoor cultivation. A good tip for cultivation in the home, stand the pot on an upturned saucer, which either rests on a gravel filled tray, or on another larger saucer, and maintain a little water in the latter, this will make the air around the plant more buoyant and help with culture.
Generally speaking, intermediate to warm loving plants do better in the home, but remember, if you live in a cold environment..... as heaters go off at night, the drop in temperature may be too much for your plant.
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