Growing Instructions - The Cattleya Alliance

Cattleyas are the classic orchid. With large, orchid-purple blooms, they are among the most beautiful and famous of all flowers. Along with these classic types, there are also many other variations in form and color so as to make the genus Cattleya far more than large purple blooms; a rainbow of colors, a plethora of forms. The Cattleya’s related genera - Brassavola, Encylia, Laelia, Schomburgkia, Sophronitis - and hybrids between them, contribute to a fantastic assortment of flower types, plant habits, culture and seasons (blooming once a year), making up what is known as the Cattleya Alliance.
This wonderful alliance is spread throughout the Americas from Mexico, throughout Central America and down both sides of South America, all the way to thePampus. This extensive geography, with its obviously varied conditions and extremes, dictates the culture for the various species.

Location: Where a plant is grown may be the most basic and influential aspect of its culture. Different types, depending on their native climate and habitat are suited for different conditions, such as growing outdoors, indoors, or in a greenhouse. As a general rule, types from high elevations are hardier and can be grown outdoors in subtropical climates, and lower elevation or tropical orchids are grown indoors or in the greenhouse. In all cases, factors such as light, temperature, water, and growing medium are most important.

Light: Bright filtered light is necessary for healthy growth and blooming (2000 to 3000 footcandles). Plants can take some sun, as in the morning or late afternoon, but too much will result in burning (seen as scorches at the point where sun hits the hardest). Outdoors, we recommend 50-60% shade; indoors, a southern exposure with some shading, or an east or west window.

Air Movement & Humidity: Air movement promotes healthy growth and helps prevent disease. Plants should be spaced to allow air flow between them; if they are grown indoors they might be placed near a window open to a breeze, or near fans. In dry conditions, humidity may be supplemented with misters under the bench (providing evaporative cooling in the summer) or humidity trays (filled with gravel and water, so long as the plant is above the water level) in the home.
Temperature: Optimum temperatures for most varieties are in the 70's and 80's in the day and 55-60F at night (although temperatures up to 100F and down to 50F are tolerable to all). Several species and hybrids grown at Santa Barbara Orchid Estate are selected for temperature tolerance (such the bifoliate cattleyas from southeastern Brazil, the fall-blooming Mexican laelias and the summer-blooming Brazilian laelias) and can take temperatures to freezing and below for short periods. We favor these kind because they thrive outdoors in subtropical climates such as coastal California; actually growing better outdoors than indoors (more robust growth and vibrant blooms). People living in more extreme climates are able to grow these types outdoors most of the year, bringing them indoors at the first frost and for the winter. (Most SBOE plants are labeled as to their temperature tolerance, or if they require warmer conditions.)

Water: Watering, like all other orchids, is done as needed. Water thoroughly so that the medium and roots are well soaked, but do not allow them to sit in water; let drain and nearly dry before the next watering.  Under our conditions, we typically water once a week with occasional wetting down during hot and dry times.  Mounted plants dry out quicker and are wet down regularly on summer days.
Shriveled or weak growth can be signs either of underwatering or overwatering! By overwatering or leaving a plant in poorly draining mix, roots will rot and consequently, the plant can no longer take up water and nutrients, thus showing symptoms of drought. This can be determined by pulling up gently on the plant to see if it still is well anchored - a healthy root system will hold onto the pot - or by pushing one’s finger into the mix - mix that has been kept too wet and has decomposed (or was poor mix to begin with) will feel soft or crumbly. If this is the case, plants should be repotted into new, firm mix. If this is not the case and the roots and the condition of the mix is fine but you are still seeing weak or shriveled growth, you might increase your watering and/or consider other factors such as light, air movement, and fertilizing.

Fertilizer: Regular feeding promotes good growth. We recommend a balanced, water-soluble fertilizer used year-round with regular waterings such as Dyna-Gro 7-9-5 or one a little higher in nitrogen such as 10-5-5.

Repotting: Cattleyas and their related types are epiphytes; in nature, they grow attached to trees and rocks, not on the ground in soil. In most cases, we find that it is unnecessary to regularly repot these types. Rather, we leave established divisions in their original pot, and when they begin to outgrow that pot, simply set the whole plant - pot and all - in another empty, slightly larger pot. The roots crawl around in the air-space between pots and the larger pot simply provides support for the plant to grow outward. Our largest specimens are often in a relatively tiny pot, set in several successively larger empty pots, with the roots exposed. As time passes, the mix virtually vanishes, or there is such a minimal amount that there is no worry of its decaying and the roots rotting. Specimens may also be set into empty hanging pots or baskets, allowing the plant to grow over the sides and onto itself for great, round displays. Typically, we only repot 1) if we are making new divisions, 2) if we are starting a plant from seed, potting up until the plant gets to its mature, blooming size 3) if the plant is declining because of decomposed mix or failing roots. When we do repot, we select a pot which has good drainage and just fits around the root ball, allowing about 1-2 years growth before the plant goes over the edge. Plants that are over-potted have a harder time getting established and the mix tends to break down sooner. Plants should be potted firmly by pressing the mix in tightly around the roots.
Orchid growers generally settle on a mix (potting medium) that works best for their plants and conditions. At SBOE, we are still trying various medium including bark, coconut chips, and rock. Plain, firm, medium-size fir bark has been quite reliable, and more and more we are potting into rock (crushed granite) which will undoubtedly never break down!

Dividing: There is nothing like leaving a plant to grow into a large specimen with multiple flowering spikes; however, plants can reach a point where they are best divided (when they have grown all to one side or lost sections in the middle), and they can easily be propagated by cutting divisions. The best time to divide is just after plants have flowered, when the new growth is just starting. Plants bloom from the most recent mature growth, and that same bulb produces the growth for next year’s flowering. Follow a plant back from its newest growth at least two or three bulbs and cut the connecting rhizome to make a two-bulb or larger division. Always use sterilized cutting tools between plants as a precaution against spreading disease.

Mounting: Indicative of their natural habit, many of these types can be mounted on trees or cork slabs. As when dividing, the time to mount is when new growth is just about to start (when they are just nubs at the base of the most recent bulb), so that the roots of the new growth can take to the slab and establish the plant. Basic divisions with one to two lead-growths are preferred for mounting; larger plants with more bulk are more difficult to establish. We prefer cork-oak slabs; other woods that are coarse in texture and resistant to decay should do as well. Select a piece that fits the plant, with room to grow upward and that suits your eye. The new division should be firmly secured to the slab with the new growth facing toward the slab in order to take to it; we typically drill two holes at the lower end of the cork and run a wire over the rhizome (the part of the plant that connects the bulbs), through the holes and tied in back. Water mounted plants frequently (weekly to daily), particularly when new growth is developing (generally April through November). Hose them down to get them well soaked, allowing them to dry between waterings. Fertilizer may be applied to the roots with a spray bottle. Bulbs are ideally plump and just as big or bigger than the previous year’s.

SANTA BARBARA ORCHID ESTATE
1250 Orchid Drive, Santa Barbara, CA 93111 +++ 1-805-967-1284 +++ www.sborchid.com