Commonly Asked Questions About Cattleyas

0rchids are increasing in popularity every day. More and more people are discovering their multiple attractions, not only as an intriguing hobby, but as appropriate and long-lasting gifts. It can fairly be said that much of this increased awareness of orchids as a whole has come as a result of the recent and rapid increase in phalaenopsis pot-plant production. Phalaenopsis seem to be everywhere. However, a survey by the American Orchid Society (prior to 1991) shows that cattleyas are still the undisputed “champ” in popularity. The Prom Queen’s corsage will always be the “mind’s-eye” image of an orchid. Although so much attention has been paid to phalaenopsis (and other) pot plants, a quiet, almost unnoticed revolution has taken place in the breadth and range of cattleya types available to the consumer. Adventurous breeders and aggressive tissue-cul­ture programs, especially in Japan, have given us an unprecedented array of colors, sizes, shapes and forms.

Cattlea Mini Purple var. coerulea
Cattlea Mini Purple var. coerulea

People will always be drawn to cattleyas; but their culture, so seemingly basic to more experienced growers, seems an impenetrable mystery to the newcomer to orchids. The mystery is compounded by the attitude that is pervasive in most available literature — that “simply everybody” knows how to grow cattleyas. Indeed, “cattleya culture” is a common description for the techniques of other orchid types. My long association with retail customers and the AOS “Ques­tion Box” has shown me that this simply isn’t the case. Many people, even some who think they are the most experienced, just don’t have a grasp on good cattleya culture. Several easy explanations for this come to mind. Because cattleyas are generally easy to grow adequately, growers are satisfied with less than the best a particular plant can do. In an almost contrary sense, some grow­ers try to make successful cattleya culture more difficult than it really is. This latter attitude can produce some very bizarre concerns to the grower. Last, despite what is widely said to the contrary, cattleyas are just not the best orchid for home growing. Oh, with careful selection as to type and a bit of extra work in providing what is not nor­mally available in satisfactory amounts in the home (i.e., light), an adequate job can be done; but optimum cattleya culture requires the conditions provided out-of-doors or in a greenhouse.

With all this in mind, it would be valuable to ask and answer some of the more commonly asked questions about cattleyas and their culture. The answers to these may seem obvious to the more experienced growers, and perhaps they are. Perhaps, how­ever, we could all learn a little more about how to grow our cattleyas to their fullest potential. Because no simple answers can be given about the “care and feeding” of any living thing, the responses may at times seem ambiguous or facile. This is not the intent. My goal is to provide enough infor­mation, symptoms, etc., to enable the grower to select what seems to be the right answer for him or her. I have yet to meet the grower who has exactly the right answer for another’s situation, and I sure don’t pretend to have it, either. The order of presentation of the questions car­ries with it no pri­ority but just hap­pens to be the order in which I originally wrote them down.

  1. Can I grow this in my home?

Of all the questions I am asked in the course of a normal year, this is the most difficult to answer in a way that both makes sense and doesn’t sound patronizing or facetious. Well, yes, you can grow them in the home, and, yes, it is okay to have them inside while in flower, but….

With sufficient light a cattleya should produce sturdy,upright new growths which do not require staking. Photo-graphy by Ned Nash.
With sufficient light a cattleya should produce sturdy,upright new growths which do not require staking. Photo-graphy by Ned Nash.

The problem with standard-sized cattleyas in most homes is twofold. First, a cattleya out of bloom is generally not a very attractive plant, so why insist on grow­ing it in the home when it might do so much better if grown out-of-doors on a patio or in a similar situation most of the year? Second, it is difficult if not impossi­ble to get adequate light to a standard-sized cattleya in a windowsill-type situation. The plant is just too big for light to reach all parts equally, given the incident (angled) light received in windows. Watering, humidity and day length are all problems in the aver­age home.

Far better, if you do not have an under-lights setup or a greenhouse, you should plan to grow the plant or plants in a protected outdoor location for the frost-free months of the year and bring them in to flower. The benefits of this scenario are many: You can use the space for foliage house­plants for the 11 months your cattleyas are out of flower. The plant will grow much better and be easier to care for out-of-doors, and it will almost invariably flower better under such cir­cumstances. Indeed, even plants grown in a greenhouse will enjoy being placed out-of-doors to enjoy the moving air and sunshine in most cases.

I can hear the “minicat” impressarios now: “Aha, but you wouldn’t have those problems with “minicats.” True, to an extent. Many outstanding cattleyas have been developed that are small enough to grow and flower well under average home conditions. Some will even have flowers that are close enough to the standard cattleya “ideal” to satisfy the grower who isn’t enchanted by small red-orange blooms. (Remember, most of the people asking these questions are real beginners at orchids and so have a mental image of a cattleya as being large and white or lavender.) It is a fact that the species that are used to “minia­turize” cattleyas have the potential to ren­der the resulting hybrids more sensitive to temperature, watering and potting season than a “typical” cattleya hybrid. Not always, mind you, but often enough so that this knowledge must be taken into account. If ever there was a customer who was able to say, “Well, that sure is a beautiful flower, but I know I can’t grow it,” this wouldn’t be such a tough subject. The lesson is, I think, that, yes, you can grow cattleyas in your home, but be prepared for some problems, some failures and some very happy successes after you have ironed out the particular technique that works for you under your con­ditions.

  1. When do they flower?

The unvoiced corollary to this question is “How often do they flower?” It is my expe­rience that probably 95% of all cattleya types are seasonal (i.e., they flower in their par­ticular season once per year). Yes, some hybrids will tend to “flush” two sets of growth per year that may end up flowering a month or so apart. And, yes, some few (very few) will flower as new growths mature throughout the year. Cattleya Esbetts, a large white, and Potinara William Farrell, an art shade, are examples of a type which can be counted on to send out a first set of new growths in summer (which “rest”) and set a second group of growths from their base before flowering in winter. While this habit is certainly desirable, and we do try to breed for it, it is not what I would consider truly flowering more than once per year. Of course, some hybrids flower on maturity of growth; the number of times per year they bloom is limited only by how fast and pro­lifically they can grow. The limiting factor in these hybrids is never — as far as I know — mentioned in the advertisements and arti­cles. Unless you live in an area where conditions permit year-round growth, such as Florida or Hawaii, multiple flowerings are the result of large plants and exemplary culture.

So, when do they flower? We are fortu­nate to be working with a group of orchids of sufficient diversity that with only a few plants, judiciously chosen, it should be possible to have at least a few flowers year-round. Cattleyas respond to varying day length and seasonal temperature fluctua­tion to “know” when they should flower.

Cattleyas, like other flowering plants, bloom at a given season when their pollina­tors are present. This is definitely a func­tion of season, the species being most pre­cise in their seasonal preference. For example, Cattleya labiata always flowers in September in the northern hemisphere; its hybrids are somewhat less precise, but a given plant will usually flower at about the same time each year. The flowering period can be grower-influenced by manipulation of day length (actually, night length) and temperature, though this is largely imprac­tical for the home grower. In past years, when cattleya cut-flower types were controlled for peak seasons, one couldn’t really know the “true” season until the plant had reverted to “normal.” But today so few plants are controlled that if you obtain a plant in a given season, chances are pretty good that it will flower then in coming years.

In a nutshell, the answer is that they flower when they flower, about the same time each year, rarely more than once per year.

  1. Why won’t mine flower?

In all fairness, it has to be said that some Cattleya-alliance species and hybrids are just more difficult to flower than others. Some examples might be jungle-collected Brassavola digbyana, some of which just never make up a flow­ering-size bulb, and some Lc. Quadroon cultivars that have gained a reputation as shy bloomers. How can you avoid such plants? The easiest way is to have a good look at the plant’s flowering “history,” espe­cially if the plant is mature. Look at the older bulbs for signs of regular flowering. Without evidence that the plant has flowered on every bulb, it is a good bet that it is a tough one to flower. The same can be said for younger plants, whether seedlings or meristems. If the plant is of reasonable size and shows no signs of having flowered, it is safe to ask why not. This is one of the dangers involved with buying young plants when a beginner. It is difficult or impossi­ble to look for the progression of bulb size and flowering history on plants only a few months out of bottle. Caveat emptor, bargain hunters.

Once you’ve made fairly certain that the plant or plants in question are not of the above type, and it should be their season to flower, you can be fairly certain that light is the problem, either too much or too little.

What? Sure, cattleyas need good light to flower —more than is usu­ally available in the home. Re­member that they are gener­ally plants of the treetops and forest edges, where they re­ceive strong, dappled sunlight most of the day.

You should be able to see a shadow (barely) as you pass your hand above the foliage. The pseudobulbs and spikes should, in most cases, stand natu­rally erect without the need of any more than cosmetic or supportive staking. The foliage is naturally a light olive green.

If the pseudobulbs are weak and spindly and dark green, the plant has not been get­ting enough light and won’t flower well, if at all. If this seems to be your problem, do not move the plant into more light all at once or it will sunburn, the same way you do if you spend too long on the beach after a long winter. Move it gradually.

Heat build-up from too much light caused the yellow patches on these  cattleya leaves. Photography by Ned Nash.
Heat build-up from too much light caused the yellow patches on these
cattleya leaves. Photography by Ned Nash.

Too much light? Well, yes, plants can be given so much light that they are too stressed to flower. This is not the most common way of giving “too much light,” however. Indoor growers, especially, can tend to think they can make up for poor quality light with quantity. That is, they will give longer hours of the poorer light in the belief that it is the total amount of light supplied, not the quality. This sort of regime is harmful in two ways. First, cattleyas for the most part are responsive to night length to trigger their seasonal flowering, and if the nights are interrupted by even a street light (sometimes), the plants simply won’t flower. Also, in the same way that if you were kept up all night, you would show signs of stress-related burnout, so will cattleyas. This causes those mysteriously burned leaf tips that seem to plague indoor growers who stay up too late at night reading to their plants.

The lesson with most orchids, cattleyas especially, is that the main reason for lack of flowering can usually be traced to prob­lems with light. Look at your plants. Do they look like they’re getting enough light to flower?

  1. How often should I water?

Here again is a hidden request: “Tell me when to water.” People do not seem to want to group cattleyas (or any orchids, for that matter) with other plants as to their water needs. The watering of container plants (any plant in a container) is influenced by a complex of factors: type and size of con­tainer, size of container relative to plant volume, season, location of plant/container, plant’s water requirements, weather and others. Not only will each of the men­tioned factors individually affect watering frequency, but they will act in concert with each other. For example, a large plant, well-established in a relatively small clay pot and grown out-of-doors, may require water quite frequently during the growing sea­son; on the other hand, a relatively small plant, recently potted into a plastic pot and grown under lights, will need infrequent watering during winter. A knowledge of how the various factors affect water use is basic to knowing how and when to water. Basi­cally, cattleyas like to approach dryness before being watered.

There are many ways which can help the grower to make his or her watering practices easier to manage. Use a uniform type and size of pot, for example. In this way, you can know that if one pot of a particular size needs water, probably all do. Arrang­ing your plants in size-place also helps in this regard. Uniform spacing of plants will help them to dry at a uniform rate. Container size or composition can be used to allow for plants that may have differing prefer-

ences for water. For instance, if a plant likes to run a little drier than most, use a smallish clay pot. Conversely, if the plant likes a little more moisture, a plastic pot can be used. Or, you can slightly vary your basic mix by adding moss for more moisture-loving cattleyas; or add perlite or charcoal for plants that like more drainage. Plants seem to be stay­ing too wet? Maybe more air circulation is needed. More frequent watering is needed during the warmer months than during cooler. Growers in more southerly climates will need to water more often than those in the north (at least in the Northern Hemi­sphere).

I think it boils down to the fact that we have no one simple answer to the question. The only person who can answer for a plant’s water needs is its observant grower. Rather than seeking a simple way out on watering, it is far better to take a moment to observe how and where the plant is grow­ing. Often, just a little observation and experience will go a lot further than sec­ond-hand advice.

  1. When should I repot? Divide? How?

Cattleyas first began to be more widespread among hobbyist growers after World War II, when the surplus of cut-flower varieties lowered their price to a point where they were affordable. The rules for when to repot cut-flower types were and are fairly straightforward. Pot immediately after flowering when the roots flush out from the flowered growth. Pretty easy, huh? Of course, there were corollaries: Pot before new growths emerge to avoid damaging them, or after the growths are at least halfway mature, so that they will form roots from the disturbance; don’t pot while growths are in bud; avoid potting after the new roots first emerge to prevent damage. As the range of available types became greater, as the hybrids began to include species with differing cultural requirements, as more species began to be grown in collections, “when to pot” became an increasingly difficult question to answer. But if the basic reason for the rule on pot­ting “standard cut-flower types” is examined, we can see that it still holds true for all Cattleya species and hybrids. Why are cut-flower cattleyas tradi­tionally potted right after flowering? Well, besides the fact that it ensures maximum time to become reestablished before the next flowering season (an impor­tant consideration when your livelihood depends on revenue from flowers), stan­dard cattleyas tend to send out a flush of roots from the most recently flowered pseudobulb right after flowering. So, when should a cattleya be potted? When it is ready to send out new roots.

These emerging new roots with bright green root tips  usually accompany a new flush of growth. Repot your  cattleya before such roots are more than an inch long to  prevent breaking them. Photography by  Charles Marden Fitch.
These emerging new roots with bright green root tips
usually accompany a new flush of growth. Repot your
cattleya before such roots are more than an inch long to
prevent breaking them. Photography by
Charles Marden Fitch.

Here is another instance where good observational habits pay off with your orchids. If you pay attention to your plants when you are watering (for example), you will note that a given type of hybrid or a particular plant will, all other things being equal, root at a certain stage in its cycle of growth, usually at the same time of season each year. Again, all other things being equal, it is hard to go wrong with potting in spring, as all living things respond to the warming temperatures and lengthening days. If you have been observant and have noticed that a certain plant tends to put out roots when the growth is, say, about half-developed, you should plan to pot that plant just before it reaches that stage of growth. This will enable the emerging roots to go right into the new mix with minimum, if any, damage or setback to the roots or plant.

You may al­so have noticed the consequen­ces of potting at the wrong time. This usually hap­pens with that one-of-a-kind, rare, expensive, newly discov­ered, award-po­tential, breedable plant that, be­cause it was pot­ted at a time other than when it was ready to root, languishes and dies. It has hap­pened to all of us. I have found that bifoliate Cattleya species are particularly sensi­tive to the timing of repotting. Some of the rarer forms of the unifoliate species can be this way as well. It makes sense in a way. Ever stop to consider why a certain plant or species is rare? Could it be that it is diffi­cult to grow and, hence, propagate? Some that have given us trouble are C. dowiana `Rosita’, C. amethystoglossa `Blue Bird’ and C. trianae ‘Blue Bird’, the single surviving selfing of which took from 1959 to 1983 to flower for the first and only time. It some­times seems to me that the only thing per­sistent about some of these harder-to-grow species is the people who just have to have a division. “Is it ready yet?” No, it grows straight ahead in a line, a bulb dying for every one that forms, and doesn’t have any appar­ent “eyes” on the backbulbs.

You should make divisions when the plant is ready for potting. But cattleyas, like most plants, do best when left to grow as large as possible before dividing. How large is large? That depends on the growth habit of the particular plant. Some will nat­urally form nice clumps, branching freely and maintaining their foliage for a period

of years. These grow with relative ease into specimen plants. The type that grow straight ahead and do not branch must either have their rhizomes severed three bulbs behind the lead or simply be kept as single divi­sions of 3-5 bulbs. When the plant gets too big to handle easily or has too many leaf­less bulbs in the center, it must divided. Don’t make the divisions too small. Keep 3-5 bulbs plus lead per division to ensure flowering the next season.

Properly positioned and staked, this cattleya division should  reestablish quickly. Photography by Ned Nash.
Properly positioned and staked, this cattleya division should
reestablish quickly. Photography by Ned Nash.

Although this isn’t really the forum for a potting lesson, a few basic hints should be mentioned. The “back” of the plant, the oldest portion, should be near the edge of the pot, with the lead growth toward the center with enough room for 2-3 years growth. The rhizome should be even with the surface of the mix, not above or below. This is the tricky part. The entire rhizome should be level with the mix surface, not just the lead bulb with the backbulbs sunk under the mix so that they are upright. If the plant is properly positioned, more often than not it will appear that the bulbs are tilted forward rather ridiculously. This is the right way! If you must, you may tie the bulbs upright, but the new growth will develop upright (assuming you’re giving enough light). Whatever material you elect to use, make sure that it is firmly and evenly packed, both to support the plant and to prevent the formation of water channels through the mix which will prevent even water distribution. Special care for newly potted plants is advocated in some cases. More shade, higher humidity and dryness at the roots are all given as aids to quicker establishing. If you have the time and space to do this, it couldn’t hurt. However, if your plants are potted as they need it, they will establish so quickly and well that the special care isn’t needed.

  1. Which is the best one?

I don’t think anyone likes to answer this one. “Why don’t you take them both, ma’am?” It’s like asking if the apples or the lamb chops are better. So much depends on who is asking and where they are growing their plants. Are green cattleyas better than lavender? Depends on who’s asking. Cer­tainly, for given situations, some types of cattleyas are “better” than others. If you are growing your plants out-of-doors in south­ern California, L. anceps hybrids are “bet­ter” than Broughtonia hybrids; while for Floridian conditions, the opposite may be true. Also, many beginners are too concerned with what the “system” says is good. If you like it, it is a “good” cattleya. It is not really fair to the person you are asking to make them state their preference when you already like one or the other better.

More to the point might be to ask how to select decent plants. What sort of ques­tions should you ask yourself in the pro­cess? Does the plant look generally healthy? Does it have roots? Are the pseudobulbs plump and upright? Is there a progression in bulb size from older to younger? Does the plant have a good history of flowering? Will it grow too big for my area? The last question to ask (usually the first asked) is “Do I like the flowers?” Of course, it also needs to be within your budget. A factor often overlooked in the acquisition of any orchid is the reliability and reputation of the sup­plier. Good cattleyas can be expensive. Would you buy a compact disc at a swap meet? Would you expect that compact disc to carry the same warranty (“express or implied” as they say) as one bought from an established and reputable dealer?

Growing cattleyas isn’t difficult. Even growing them well is easier than growing many of the more popular genera (miltoniopsis leap to mind). Growing them can be made difficult, if one insists. Obtain reli­able plants from reputable sources and use your common sense. Cattleyas are the most popular orchids for a reason. Maybe now is the time for you to find out why.

Article by Ned Nash, published in the “American Orchid Society Bulletin”, September 1991.