Top Ten "Uncommonest" Questions Asked About Phalaenopsis

Q. My phalaenopis has a bloom spike arising out of the apical crown of the plant. What effect will this have on future flowering?

A. Probably this means that your plant has reached full maturity, and it will cease to grow and flower after this spike is finished. However, we've seen some plants resume growth, and thenceforth act in a normal manner. Some say this atypical flowering results from too much light; others blame insecticides, especially the systemics. A plant that does not resume normal growth will usually throw one or more new plants or "keikis: from the base of the plant, so don't throw it away. Until it does produce new plants, continue to treat it in a normal manner.

Q. My phalaenopsis plant has grown quite tall. How can I "top" it?

A. Select where you will cut the plant by examining it carefully, and determining a point where the cut will leave the top half with an ample root system to sustain it until it becomes established. You can remove the bottom part and repot it, or leave it "as is". To pot the top, be sure to cut off any leaves that will be below the potting media, and of course, use only a sterile knife. Remove any flower spikes to force growth energy into the division. Seal all wounds and cuts with a tree-seal paint. Withhold water from the bottom half for a few days to allow the injured roots to heal. Then keep it slightly on the dry side until one or more "keikis" appear - from one to six months. They can be removed when the roots are one to two inches long. As long as the bottom half remains alive, it will continue to produce, perhaps as many as six or more "keikis". You can give slightly more water than is usual to the top half until it is well established.

Q. When buying phalaenopsis seedlings, what kind of shape and color should I look for in the leaves and root tips to assure fine flowers?

A. We know of no correlation between flower shape and size, and the shape of the leaves or color of the root tips. On our bench of stud and award plants, you can find every type of leaf shape: pointed, rounded, long, short, etc. Certainly, in buying seedlings with color expectancy, you'll want a plant with some pigmentation in the leaves and/or root tips. But again, there doesn't seem to be any correlation between the amount of color visible in the plant, and the intensity of color in the flowers. From our experience, the only assurance of fine progeny comes from the use of fine parents. Of course, there is no hard-and-fast guarantee of success but the odds are in your favor.

Q. My phalaenopsis plant grows quite well, but doesn't bloom. Why?

A. One reason could be too high temperature. We find that phalaenopsis flower quite well at 62 degrees F. If you are growing the plants indoors, artificial lights nearby might cause long days and thus inhibit flowering. If the plants seem to be growing well, water and fertilizer applied as directed, temperature ideal, and still no flowers, then not enough light is probably the answer. Gradually increase the light intensity until you have about 1000 to 1500 footcandles, or roughly all the light the plants can take without burning. If growing in the home, move the plants to a nice, bright windowsill that receives an hour or two of direct sun in the very early morning or late afternoon.

Q. My phalaenopsis never quits blooming, and is badly in need of repotting. What should I do?

A. Repot it - now! We repot year round as the plants need it. If the plant is healthy and robust, you can leave the spike on. If, on the other hand, the plant is a seedling, is weak, has a poor root system, or if you are apt to damage a goodly number of roots in repotting, then sacrifice the spike to force growth energy into the plant.

Q. I seem to get a lot of crown rot in my Phalaenopsis. What can I do?

A. Prevention is the best answer. Always water your plants before noon, or so the plants are dry before the falling temperature in the evening. Keeping your plants slanted or at an angle make help keep water drained out of the crown. A regular spray program - especially in hot, humid areas - with a good fungicide will pay off.

Q. The buds on my phalaenopsis spikes open at funny angles, spoiling the spray arrangement for show and award purposes. Why?

A. Once the buds start to form on the spike, and after staking up the spike, leave the plant absolutely alone in that position. Phalaenopsis spikes (as with most flowers) tend to draw toward the light; the buds will twist and turn back toward the light each time the plant is moved, thus spoiling the arrangement

Q. I'm having trouble getting "takes" when trying to makePhalaenopsishybrids. Many times the ovary stays green, starts to swell, then turns yellow and falls off. Or, I may get a seed pod, but when I sow the seed, get no germination. Can you help?

A. Many of today's so-called "novelty crosses" are triploids, or have very unusual or dissimilar chromosome numbers. After pollination, hormones produced when pollen is introduced onto the stigmatic surface may start the ovary ripening. However, when fertilization fails to occur, the hormone process stops, and the ovary (old flower stem) turns yellow and falls off. We've found too, when crossing a small flower with a large one, pollen tubes produced by pollen from the small flower just aren't able to grow long enough to reach the ovules in the large flower. We always use pollen from from the larger flower onto the smaller flower. Another interesting point: after almost giving up trying to hybridize with certain plants over a long period of time, all of a sudden they seem to breed with almost anything - a kind of "puberty" some have suggested. We, and others, have used triploids successfully in breeding, so don't give up, although it may take many, many attempts. Dr. Sagawa has suggested that in certain complex hybrids many or most of the embryos may be dead by the time the seed pod matures. For this reason we use only green-pod or embryo culture methods, and take the pods about 120 days after pollination.

Q. I've heard that there's a lot of unexplored territory in breeding phalaenopsis, especially with some of the species. Where should I start?

A. First you might start by looking in Sander's List of Orchid Hybrids (AQ plus, RHS New Orchid Hybrids) to see what species have been used, and what ones have not. Once you find a little used species you would like to breed with, make certain you are, in fact, using that species… You'll probably have to grow 100 or more seedlings along in order to see a fairly accurate cross-section, but with good care, you should see most bloom within three years. You might also check catalogs, Orchids magazine articles, and contact hybridizers…to get more information on what has been done, and get some tips as to where to proceed.

Q. How can we assure a good phalaenopsis crop for a certain holiday or show?

A. Dr. Rotor, in Withner's book The Orchids, reports that short days and/or low temperatures induce flower initiation. He used Phal. amabilis, Phal. schilleriana and Phal. schilleriana hybrids with short days (black cloth) and a low temperature of 65° F. Long days (artificial lighting) delayed flowering. We've never experimented with black cloth or lights, but get continuous, year round spike initiation, we believe because of our cool (60°-62°F) night-time greenhouse temperatures. We are currently running a series of tests to determine the optimum low temperatures for spike initiation and how long it takes a plant to initiate a spike at that temperature. We feel that by using black cloth to delay flowering until a specific time - if for an extended time - would be detrimental to the plant's vigor, and possibly cut down on subsequent flowering.

George P. Woodward, Jr. (Santa Cruz, CA)
reprinted from the American Orchid Society Bulletin - March 1968