It is very important to understand in what climatic conditions Phalaenopsis will thrive best so that we can create similar ones as close to their natural habitat as possible. They are warm growing plants and therefore heating is required at a minimum temperature of 65° F. and maximum up to 80°F. This means that in summer ventilation of some sort may be necessary, such as an extractor fan controlled by a thermostat, or roof vents. They like lots of light but not the direct sun . Efficient shading is required in summer time, may be up to 70%. On the other hand in winter or when the light drops below 1500 candles , especially if you are growing seedlings, halogen lights will compensate the light and speed up the growth, which will make a great difference. Next we have to consider air circulation by using electric fans. This air movement is just as important in culture as anything else. The last thing to take into consideration is the humidity. The plants require a humidity between 70% and 80%. To obtain that we need some sort of floor watering such as an under bench water sprinkler and some sort of fogging device for the larger greenhouse. Both of these can be automated by connecting through a humidistat. An example of a fogging system which could be improvised is by using a car wash high pressure water pump and reducing the outlet to an 8 mm copper tube onto which you can connect a few very fine nozzles. You can then mount this high up in the greenhouse and it will produce reasonable fog. To control it, you connect it through the humidistat control and time switch and of course the water intake is from a rain water tub or tap if your tap water is suitable. See diagram below.
The resulting fog and the humidity at about 80%
Now that we have created ideal growing conditions, let's concentrate on the plants. As Phaleonopsis plants do not have pseudobulbs, the strength of the plants is in their leaves and fleshy roots. The leaves are leathery and large. It is important that you have both of these things in mind when you are dealing with the culture. The compost should be evenly moist at all times, not soggy wet or dry; both of these will kill the root system. That means the compost we choose must have good drainage and at the same time retain moisture. I prefer to use medium bark mixed with moss, and a little bit of perlite (approx. ratio 8 to 1 to ½ perlite). Make sure that the pots are not flat on the bottom, otherwise as soon as you put them onto a flat bench the drainage will stop, and it would be even better if they had additional holes on the side.
The next important factor is the quality of the water you use. Tap water varies from area to area. For example, my tap water is very hard and measures about 550ms using a conductivity meter. So using rain water or reveres osmosis water is a much better choice. Remember that the water temperature should be the same as the greenhouse temperature, and also you may need to water twice or even three times to start with to keep the compost wet. And water only when necessary. You can judge if a plant needs watering by lifting the pot and it will be very light if it is too dry.
To feed the plants, use a well balanced fertilizer such as Peters 20-20-20 at about 300ms or 150 ppm., using a conductivity meter to measure the amount (approx. ¼ tea spoon per gallon of water) or Dyna-gro Liquid Grow (7-9-5) at ¼ tsp per gallon of water. Every 4th watering rinse the compost well with clean water by watering several times . This is to reduce any excessive salt accumulated in the compost. Measure the last drop of water from the bottom of the pot using a conductivity meter. The reading could be very high. Too much salt kills the roots.
RO water or rainwater is about PH 7.1, but after adding fertilizer to it, it drops to below PH 6.5. Phalaenopsis absorb most of the trace elements between PH 5.5 and PH 6.5. If you wish, you can adjust the PH.
I suggest watering the plants early in the day so that the leaves are dry by the evening. And don’t leave any water in the crown, otherwise it will rot. You may on a sunny day foliage feed using seaweed extract fertilizer. It may be also helpful to feed with Epsom salts once or twice a year.
If you keep water in the tank too long and it becomes stagnant, it is more likely to develop bacteria known as psudonomea cattley . This will rot the leaves . You can use a pinch of permanganate of potash in the tank, which will kill the bacteria. It is also useful to spray systemic bactericide / fungicide such as Dithane, Physan 20 or Kocide 101 once a month to cope with the threat or danger of rot especially in the winter time.
Keep the plants clean from insects and pest (scale and mealy bug) by using Provado spray or brush them with methylated spirit or any other good products. Slugs are controlled best by using slug spray or pellets.
Another very distructive insect on Phaleonopsis is False spider mite, known as Tenuipalpus pacificus or Phaleonopsis mite. With their needle- sharp mouthparts, they puncture the epidermis of under leaf of Phaleonopsis and suck out the juices. this causes the leaves to go yellow and the turn brown and fall off.
If detected in time False spider mite can be easily controlled with Provado spray.
It is good practice to re-pot at least once a year or every 18 months with fresh compost.
If you follow these simple rules you are most likely to enjoy a good crop of flowers. They are some of the most rewarding orchids to grow.
To sum up, Phalaenopsis grow throughout the year with little or no rest, but they grow faster in brighter and warmer conditions
C. KovacBack to top