Common Name: Spitz's Catasetum [Brazilian Orchid Enthusiast 1900's]
Flower Size: 2.4 to 2.8" [6 to 7 cm]
Found in Brazil and Bolivia at elevations up to 800 meters in subtropical forests as a medium sized, hot to warm growing epiphyte with short, fusiform pseudobulbs carrying several, plicate, narrowly elliptic, acute leaves that blooms in the fall on a newly developing pseudobulb with a basal, 16" long [40 cm], horizontal, several to many [11 to 35] flowered inflorescence carrying color and size variable flowers.
This plant needs a decided rest after leaf fall and should get little or no water or fertilizer until new growth appears.
Internet Orchid Species Photo Encyclopedia. Photo courtesy Fred Clarke of Sunsey Valley Orchids
There are about 100 species in this more popularly grown genus. Vigorous growers that are less sensitive to cultural mistakes, Catasetums are the most easily grown members of the Catasetinae. Floral dimorphism, the production of male, female or hermaphrodite flowers, sometimes very different from each other, is a trait that adds interest and initially caused confusion. The showier male on the left (staminate) flowers that can eject their pollinia and the yellowish-green female on the right (pistillate) flowers usually grow on separate inflorescences that arise from the base. Occasionally, hermaphroditic flowers are produced, and at times male, female and sometimes hermaphroditic flowers can all bloom on the one same inflorescence depending on specific environmental factors. For instance, growing under greater sunlight tends to produce more female flowers.
Catasetinae are heavy feeders during their growing period but a dry rest period of differing lengths according to species is needed after flowering, specifically, once the plants start to drop leaves. Water is gradually reduced, then withheld. If at all, water sparingly only to prevent pseudobulbs from shrinking too much. Once new growth reaches 4 inches and new roots reach 3 or more inches long, watering is begun, with normal abundant watering taking place once the potting mix again approaches dryness. Fertilize well during the active growing season as the plant does not get a chance to be fertilized during its dry rest period. Catasetinae like humidity of 50-70% with warm day temperatures of 75-80 F (24-27 C) dropping 10-15 F (6-8 C) at night. Repot just as new growth is beginning at the end of the dry rest.
Catasetinae Plant Culture
Cycnoches, Catasetums, Mormodes, and Clowesia
The cultural information below is a generalization and will apply in most situations; however each grower and growing environment is different. I encourage you to make adjustments based on your own experience and growing conditions.
Catasetinae have a distinctive growth and rest period (dormancy). For best plant growth it is important to understand and respect these growth phases. When the plants are in active growth maintain constant root zone moisture and fertilize regularly. This is essential to optimizing the development of new growth. When the plants are dormant little or no water is needed as the pseudobulbs store enough moisture and nutrients to survive the dormancy.
Catasetinae plant culture is not difficult. All it takes is an understanding of the seasonal growth patterns. The plants' vegetative state signals to the grower their changing needs. Interpret the signals and make the appropriate cultural adjustments. Here is what to look for:
Catasetinae begin their new growth in early spring. However, watering should wait until the new growth has well-developed new roots. This means you should let the new roots grow to an approximate length of 3-5” before you begin watering. Let me emphasize this point. Wait to water until the new roots are welldeveloped. The waiting to water is not easy; my natural instinct is to begin watering when I see new growth, but I have learned through trial and error that it is better to wait to water than start watering too soon. I also believe that Catasetinae roots deteriorate during dormancy, and in the following year they are not as effective at taking up moisture and nutrients. This makes the new roots vital in the plants' health. This reinforces the message about not watering too early.
Once the new roots are sufficiently developed, this is the period where the plants are rapidly developing their new pseudobulbs. There is a surprising amount of growth that occurs in these 3-4 months; often the plants will double their size. Due to this, the plants require constant moisture and regular fertilization. In most cases, irrigation will be needed 2 or 3 times a week. A balanced fertilizer at full strength is suitable for this rapid growth. Light levels at or above those suggested for Cattleya will help insure strong good growth and flowering. This is the time when the fruits of your labor will begin to pay off as the flowering season is in underway.
Sometime after flowering, in the late autumn the plants will begin to enter the dormancy phase. Understanding the signals of the onset of dormancy and the factors triggering it are important to a healthy plant culture. The plant's first signals are the yellowing and browning off of the leaves, at this time stop fertilizing and reduce watering by one-half and when most leaves are yellow/brown and have dropped off cease watering altogether. The general rule to follow is: by the 15 th of November stop fertilization and reduce watering by one-half. Most leaves should have yellowed or fallen off by the 1 st of January. However, if the plants still have leaves all irrigation should be stopped at this time.
The onset of dormancy is caused by several factors; the maturity of the pseudobulb, shorter day length, cooler day/night temperatures, and a reduction of root zone moisture. In most of the country dormancy occurs naturally; however when the plants are cultivated in warm growing areas such as in South Texas, Florida, Hawaii, or in the home or under lights sometimes dormancy needs to be encouraged. I have found that stopping watering in early January regardless of the number of green leaves will trigger the dormancy.
Note: Watering during dormancy should only be done it the plant shrivels severely. Usually a single irrigation is sufficient to restore the bulbs.
Here's a summary:
- As the new growth develops wait to irrigate until the new roots are well-developed and are 3 to 5” long. (Don't be in a hurry to water; it is better to wait)
- Irrigate and fertilize frequently while the plants are in active growth.
- Stop fertilization and reduce irrigation by one-half around by mid November.
- Cease watering by the 1 st of January.Light levels: Catasetinae like light levels comparable to Cattleyas at about 2500-4000 foot candles (fc) However, the plants are widely adaptable and do well with light levels as low as 1500 fc and as high as 5000 fc. For optimal growth I suggest a Southern exposure or a location where all the plants will receive plenty of bright, filtered light
Potting mix: For mature plants I have been using a 3:1 of mix of fine ‘Kiwi Bark’ and medium Perlite. For seedlings up to a 3” pot size I like to use New Zealand sphagnum moss with the bottom 1/3 of the pot filled with Styrofoam peanuts. However, this genus is not too particular in what it is potted in, and any well drained media will work well.
Containers: I prefer to grow in plastic pots; however clay pots, baskets, and cork slabs will all work. Catasetinae don't like to be over potted; select a pot size that will allow for 2-3 years of rowth.
Fertilizer: When in active growth, regularly use one teaspoon of your favorite fertilizer per gallon of water.
Air movement: Catasetinae enjoy abundant air movement. If you are growing in a green house use air circulating fans. Also, hanging the plants allows for maximum air movement around them and often they do best hanging.
Repotting and Dividing: Is done as the new growth is just starting to develop and before the new roots start to show. (Remember no watering until the roots are well established, 3-5” long). Unlike most orchid plants Catasetinae do well when divided in to 2 bulb pieces. Divisions are made by cutting with a sterile tool or by pulling the bulbs apart. I try to keep the size of my plants between 2 and 5 bulbs.
Insect pests: Catasetinae are generally pest free. However spider mites are attracted to the soft leaves of these plants. Spider mites are quite small.They live and feed on the undersides of the leaves. Take care in checking for them as the plants are developing the new leaves and control them with a recommended mitcide from your garden center. Although the leaves will drop off during dormancy this is not an excuse to not treat for them.
Stephen's Catasetinae Culture
Catasetum, Clowesia, Cycnoches, and Mormodes are the primary genera that compose the catasetinae. They can be grown easily without the necessity of a greenhouse. They can grow in just about every kind of medium that you can imagine. Here's how Stephen grows his catasetums.
I grow all of my plants outside under a large shade house covered with 60% shade in the growing season and bring them into the greenhouse when the weather turns cold and they begin their dormancy.
I have seen them grown in rock, lava rock, rock wool, and all of the other orchid potting materials that are on the market. I use a mix of one part large sponge rock, one part medium charcoal, and one part peat moss. The pots are top dressed with a sprinkle of time release fertilizer and a thin layer of sphagnum to keep the fertilizer from splashing out. Since I grow outside under shade cloth I pot all my Catasetums in clay pots. They dry out faster and I do not lose any plants to rot whenever we have those months of rain every day for weeks at a time.
Spring Growth Cycle.
In the spring they will send up a new growth and start the growth cycle all over again. This is the time to repot the plants. Remove the plant from the pot and cut most of the old roots off. Leave enough of the old dead roots on to stabilize the plant. Repot the plant slightly below the top of last year\92s growth and position the new growth in the center of the pot. Move the plant to a warm growing area where it will get moderate light. DO NOT WATER AT THIS TIME! Wait until the new growth opens up with a leaf span of \BD to 1 inch across. Only then do you start to water and feed the plant. Any old back bulbs can be cut from the plant and repotted in a dry mix. They will send up a new growth in a month or so.
Growing Season Care.
Catasetums are heavy feeders and like a lot of water during the spring and summer. However, they do not like to be kept wet for an extended period of time.
Bring the catasetums into the greenhouse only when the weather turns cold in October. By this time most of the plants have begun to shed their leaves and begun their dormant period. At this time I do not water or feed them unless they are still in an active growing stage. Many of them will also be in spike and will be blooming for the second and third time. The plants should not be exposed to temperatures below 55F for an extended time. They can be kept on a window sill or somewhere in the house in the winter without any water or sun light.
Another significant advantage to growing Catasetums is that scale does not seem to favor these orchids. I have some trouble occasionally with mealy bugs and spider mites. I use a new product called Sorbishield that is a sugar based, nontoxic product for spider mites and mealy bugs and other soft bodied pests. So far this product has been very good.
Catasetum spitzii 'SVO Gold'
Catasetum spitzii 'J.E.M.'
|1999-02-13||CHM||AOS||81||JEM Orchids, Delray Beach, Florida|