platinum coast orchid society

Orchid Culture

photo courtesy mawilkinson.com

The following are a collection of articles written by Society Members and published here, for all to access:


What Is It
Have I Got It Already
What About Cultivars
Who's Your Daddy
Is It Real
Curing Black Spots on Cattleyas
Orchids and Availible Water sources

What Is It?

By Craig Helpling


So, you bought that new orchid at our show, but what is it? Does it have a simple name, or do you have to try to pronounce some lengthy hybrid combination? Here's how to find out. Whether you can get access to the Internet with a home computer or at the public library, the Royal Horticultural Society can help. The recognized international authority for registering orchids, they maintain a web site that provides easy access to their official information called, "The International Orchid Register." Start at the address: http://apps.rhs.org.uk/horticulturaldatabase/orchidregister/orchidregister.asp. Click on Parentage Search. On the next page you'll find four boxes. Using the label on your new orchid, enter the information in the same order. You do not need to enter all of the details. For example, with the hybrid Blc. Ruth Davis x ("x" means "crossed with") Toshie Aoki, you can enter only those parent hybrid names in the boxes marked "Grex." Then click on the word "search" at the bottom. The next page gives the results: Brassolaeliocattleya Hawaiian Features. That is now the grex, or registered hybrid name, of that popular cross. Click on the Hawaiian Features name and the next page will show you the details of the registration. You now know you actually own a Blc. Hawaiian Features! If no result comes up, it means the cross has not been registered yet and you'll have to continue identifying it by the lengthier name on the tag.

Have I Got It Already?

By Craig Helpling


In the last article, we looked at how to see if your new plant has a hybrid, or grex name registered in The International Orchid Register maintained by the Royal Horticultural Society. Besides trying to find out if you can refer to your orchid with a single name, there is another practical aspect to using this web-based resource. Orchid hybridization is a BIG business. Thousands of new crosses are created each year. If a cross eventually becomes a successful one that people actually want to buy, they are usually registered. However, there can be a significant delay in how soon that registered grex is used in common practice. For the Blc. Ruth Davis x Toshie Aoki, the single grex name Hawaiian Features was created on November 30, 1998. At our show recently, I saw vendors selling orchids labeled Blc. Ruth Davis x Toshie Aoki. I also saw Blc. Hawaiian Features for sale. Both labels are correct, but if you bought both, you now have two of the same orchid! If you have an "orchid wish list" you are looking for, it would be a good idea to regularly check the web site: http://apps.rhs.org.uk/horticulturaldatabase/orchidregister/orchidregister.asp to find out if a cross has been registered yet. If so, you will know to look for the name either way. That will keep you from buying multiple plants of the same kind, unless that is your goal!

What About Cultivars?

By Craig Helpling


The web site of the Royal Horticultural Society provides a great deal of information about registered orchids in The International Orchid Register. At an orchid show, you will find established crosses that have been given a grex, or hybrid name. You will also find the latest and greatest crosses, some of which are destined to become popular, but have yet to be registered, even if their parent are. You may even find older hybrid crosses listed that have not been updated with the newer grex. (In a future article, we'll also see that some names may never be registered, a decision of the hybridizer.) But what about awarded cultivar names? When an orchid receives an award from the American Orchid Society, for example, the owner of the plant can add a cultivar name. Remember the Blc. Toshie Aoki used as an example on how to search the RHS web site? The actual Blc. Hawaiian Features I own was made with Blc. Ruth Davis crossed with Blc. Toshie Aoki 'Pizzaz'. The 'Pizzaz' variety, cultivar, of Blc.Toshie Aoki is very popular, but it is not distinguished from any other cultivars in the RHS database. Omit the cultivar name when searching. So, even though an awarded status of the parent plants is not reflected in the RHS web site, it is still interesting to see what is registered. I have learned that my Ascd. Jiraprapa crossed with V. Rasri Gold is registered as Ascda. Jakkit Gold. The Mokara Sayan x V. Rasri Gold is Mokara Yellow Star. And finally, my Ascda. Pudtan x V. Manuel Torres is known officially as Ascda. Newberry Blue Skies.

Who's Your Daddy?

By Craig Helpling


Have you wondered how your favorite orchid hybrid was created? The International Orchid Register database can help. Visit the web site of the Royal Horticultural Society http://apps.rhs.org.uk/horticulturaldatabase/orchidregister/orchidregister.asp to find out not only 'Who's your Daddy', but 'Who's your Mommy' as well. At the site, scroll down and click the link Grex Name Search. On the next page, enter the grex, or hybrid name on your plant's label. For Blc. Ruth Davis, put Brassolaeliocattleya in the Genus box and Ruth Davis in the Grex box. Note that the common genus abbreviations will not work. You cannot enter Blc., but you can get by with entering only the first letter, B with no period. Then click search. The next page shows the "Daddy" and the "Mommy"! Blc. Ruth Davis was created by taking pollen from Blc. Oconee and crossing it with the seed from Lc. Bethune. The name Ruth Davis was registered for this cross by Carter & Holmes in 1992. Now you know. This can be very helpful if you want to enter an orchid for AOS judging. The registration form requires that the parents be listed. Use the database to find out. Knowing the parents can also help uncover clues as to how to care for your hybrid. You can keep tracing the parents back to the species that are the Original Parents of every hybrid. Besides being able to trace your orchid's "family tree" this way, the identity of the species may help you understand what kind of cultural conditions could benefit your orchid. Beyond all that practical stuff, it's just fun!

Is It Real?

By Craig Helpling


All new hybrid crosses start with species plants, with hybrids that have been created, or with any combinations of the same. New grex names are not usually created for the hybrid cross until after the plant is successful, which means people want to buy it! The Royal Horticultural Society maintains The International Orchid Registry. Here, official hybrid, or grex, names are registered for new orchid crosses. There is a fee for registering the grex name, but it allows the orchid hybridizer, the vendors, and the potential customers to all know, at least in general, what the orchid is. But, not all orchids are registered. I have an orchid labeled Dtps. Man Chung Hong. That may be a real name in somebody's world, but it has not been registered to date. That also means I cannot find out its parents. It cannot be entered in AOS judging, either. The label does not give any hint that it is unregistered. At our show, at least one vendor was selling an unregistered hybrid. The tag said Phal. Anthura Gold. However, the vendor was honest; the tag also said in parentheses, "Not Registered." I have seen, and even own, other orchids with the word 'Anthura' in them: Dawson, Dublin, Halifax. But, using the RHS web site, you will discover that no orchid of any type has yet been registered with the name 'Anthura' in any portion. Go to the web site www.anthura.com and you'll find the source of these orchids explained in the native German or in other languages including English. All are very nice orchids, but simply not "real" as far as international recognition is concerned.

Curing Black Spots On Cattleya Leaves

Charlie Bishop has discovered a new treatment to cure black spores on catt leaves. The tip of a new growth on a 'Lc Mary Elizabeth Boyd Royal Flare' started turning black, as though rotting. He cut the leaf back to healthy tissue with a sterile clipper, and treated the open wound with Ban-rot, a powerful fungicide. A week later, the area beneath the wound started turning black, and he used the same procedure. Another week and the same thing happened. So he figured it might not be a fungus, but a bacterial infection. Reasoning that a human might use triple antibiotic ointment for a bacterial infection, he mixed a small amount of the antibiotic ointment with Ban-rot to make a thick paste, and applied it to the fresh wound. Not only did the infection not recur, but the pseudobulb on the leaf produced a sheath and ultimately three flowers. Charlie points out that this does not prove that the antibiotic ointment was the curative agent, since it is an oily substance. Perhaps Vaseline would do just as well. Further experiments are ongoing.

Orchids and Availible Water Sources

By Craig Helpling


Reclaimed Water

Some of the public wastewater utilities in our area have reuse programs to manage part of their treated wastewater. The raw sewage arriving at the plant is treated by various methods to produce effluent that fully complies with state law. This treated, 'reclaimed water' is pumped from the treatment plant back to some neighborhoods and is safe to use for irrigating residential lawns and landscaping. Is it good for orchids?

Reclaimed water usually does not contain a lot of nutrients, such as nitrogen or phosphorus. State rules require the wastewater to be treated to remove such nutrients. What 'safe' really means for reclaimed water is that it has also been treated sufficiently to remove all harmful bacteria and viruses. But, even though reclaimed water has very low nutrient content and contains no bacteria or viruses, that does not mean it is always ideal for use on orchids.

The state rules for domestic wastewater treatment do not address total dissolved solids. Dissolved salts and other minerals are in the raw sewage when it gets to the treatment plant. The biological, filtration and disinfection methods used at the plant to clean up the wastewater do very little or nothing to reduce those mineral and salts.

When the water in the ground is influenced by brackish or salty water, it is common for the domestic sewage arriving at the plant to be more salty than the wastewater leaving the houses. Sewage collection pipes and manholes, especially ones built many years ago, often leak. But, with a high water table and deep sewer lines, raw sewage does not leak out; ground water leaks in. Commonly on the barrier islands, it is more likely that the ground water is salty and this infiltration adds dissolved solids to the collected sewage; dissolved solids that won't be removed by the wastewater treatment processes.

Reclaimed water that is low in total dissolved solids content can be an ideal source for irrigating orchids. However, whether you live on a barrier island or on the mainland, it's best to make sure how salty the reclaimed water is before you use it. Take a sample to the local Agricultural Extension Office and ask that it be tested. The service is free. When you get the results, then decide if it might be good for your orchids, or if it is so salty it might damage them.

Well Water - Shallow and Deep

In most of the central and southern areas of our county, water wells used strictly for residential irrigation come in two versions: shallow and deep. (Please note that this article does not apply to private wells used for drinking water. That will be addressed separately.) While there is no specific depth used to distinguish between the two, there is one general important difference. A shallow well withdraws water from the surficial, or water table aquifer. A deep well obtains water from one or more zones that are under artesian pressure. Deep wells usually flow some due to the pressure and shallow wells do not. Both use well pumps to provide pressure to a home irrigation system.

Instead of the specific depth, the more important distinction involves the quality of the well water. Again in general terms, shallow wells usually provide less salty water than deep wells. However, shallow wells can contain a lot of iron salts that cause rust-colored staining. Deep wells don't usually have much iron content, but they always contain higher mineral salts and some hydrogen sulfide that produces a rotten egg odor.

For both types of wells the advice is the same. Before using either one to water your orchid collection, take a sample to the Ag Center and have it tested for total salts. Water from some shallow wells may prove to be a good source if the salts are low enough. The water quality from deep wells will invariably be too salty for orchid growing.

Rain Water

One of the most ideal sources of water for orchids is rain water. If you grow orchids outdoors – under trees, in a pool enclosure or screened lanai, or in a shade house – you probably know how well orchids respond to a good rain. After all, species and natural hybrids survive in the native habitat with only rain, dew and humidity supplying the needed moisture. But rain provides more than just water.

Rain is good for orchids, but not because it is a "pure" source of water. If distilled water can be considered as pure, containing no dissolved solids or nutrients, rain by comparison is quite the opposite. Rain water is usually 'soft', containing only low levels of dissolved solids, and that can help leach out any excessive fertilizer salts that tend to build up. But besides containing small levels of micronutrients, rain can also contain some of the fundamental primary nutrients required by all plants.

The atmosphere is composed chiefly of dinitrogen gas, N2. This combination of two nitrogen atoms is very stable, with strong molecular bonds. However, the forces holding the nitrogen atoms together are no match for another natural phenomenon, lightning. The power in a lightning bolt literally splits the dinitrogen gas molecules apart, creating nitrite, nitrate and ammonia. These components are picked up by the condensing moisture, becoming part of the rain. This natural process becomes one of nature's ways of fertilizing plants, including our outdoor-grown orchids.

But, the problem we face is the timing of the rains. We seem to get too much or too little to fit our preferred cultural practices. So, how can you make use of rain water on your schedule? A rain barrel is the simplest answer. Positioned to receive rain running off the roof of the house, rain barrels can collect and store the water for your use. Except during prolonged drought periods, this stored rain water can be used for general irrigation, or as a source of good water to mix with your fertilizer program. A delivery system, such as a pump sprayer or electric pump, is needed to water your orchids.

Pond & Lake Water

Modern subdivisions in our state often include one or more lakes. Besides the obvious marketing motivation of offering "waterfront lots", there are more practical reasons for finding so many lakes in planned residential neighborhoods.

First, many land parcels are not high enough to build on. They could experience flooding if left at their natural elevation, in violation of local land planning regulations. To correct that problem, fill dirt is needed to raise the land. Developers often dig lakes and ponds to obtain their own fill to build up the lots and minimize the flooding potential.

To further minimize the flooding potential and offsite water pollution, land development regulations also require developers to manage storm water. The same ponds and lakes dug as borrow pits for the fill dirt, often conveniently serve the storm water retention needs of the development.

Since they are designed to receive storm water, it's logical to conclude that the ponds and lakes contain very fresh water. That would then mean the water would be a safe and good alternative for watering orchids. But, whether pond and lake water in a subdivision is actually ideal for orchids depends on a few factors.

Most retention ponds are semi-closed systems. They are designed to receive and hold most of the rainfall runoff, allowing it to percolate into the ground or evaporate. Overflows are provided to off-site systems by design to minimize flooding inside the neighborhood, and work only during high rain periods. This means that the lakes and ponds do not get 'flushed out' very often. Even when they do, the typical overflow system removes the waters flowing near the surface, not the water stored at depth.

Storm water entering neighborhood retention ponds comes from land and street runoff, which means it can carry a multitude of contaminants with it. Fertilizer nutrients, pesticides, herbicides, oils, and organic constituents can all be carried into the ponds and lakes. Many of these contaminants undergo change within the ponds, subject to natural chemical and biological processes. However, over time, the amount of total dissolved solids can increase in these relatively closed ponds. The salts and minerals have a tendency to concentrate, left behind by evaporation and percolation. The pond water may not really be as 'fresh' as rain water, especially if the neighborhood has existed for some time. Before using pond water on your orchids, go see the Ag Agent with a sample. Be sure the water is actually as clean as you thought, or at least within an acceptable range.

Drinking Water

In most cases, if the tap water from your faucet is good enough for you to drink, it's good enough for your orchids. That comment and the ones that follow are true if you receive your potable water from a public water utility. (However, one caution: If you have a home water softener, see the next article on 'Softened Water'.)

Municipal and even privately-owned public water utilities are subject to federal and state rules that apply to the quality of water that can be sold for human consumption. Regardless of the original supply source of that water, the treatment, filtration and disinfection requirements are intended to ensure public health and safety. Drinking water regulations apply to total dissolved solids, pH, hardness, chloride, metals, and a wide range of other parameters. The public utility cannot deliver water to your residence that does not meet all of the applicable standards.

Some people have expressed concern that chlorine used to disinfect drinking water may be harmful to orchids. Actually, chorine is becoming less common in public water treatment systems. Utilities are opting for other chemical and physical processes, such as UV light disinfection. (If you keep tropical fish, you may know that some chemical processes may be harmful, but that same caution does not apply to plants.) No matter what disinfection method is used, there is very minimal risk, if any, to your orchids.

The only real drawback with using drinking water to irrigate an orchid collection is cost. If your house is also connected to a public wastewater treatment plant, not only do you pay for the water treatment of each gallon of water you use, you also pay for each gallon to be processed by the wastewater treatment plant. That's because the billing for both drinking water and sewer service is based on your water meter readings each month. It does not matter that the water used on your orchids does not enter the sewer system. If the water went through your water meter, you pay for both services.

Drinking water from a public utility is a very good, stable source of irrigation for your orchids. With proper attention to careful watering practices and habits that conserve water, you can keep a healthy collection of orchids without paying an exorbitant cost for irrigation.

Softened Water

A number of people use water softeners to treat their home drinking water. Water softening equipment is commonly used when a private well provides the drinking water for household use. However, a growing number of people are opting to install a whole-house water softener to further treat the drinking water received from a public water utility. While the first example may be an unavoidable necessity, the second should be very carefully considered since it could be not only a significant waste of money, but a possible health threat as well.

In either case, water that has been processed through a water softener should never be used on orchids!

Conventional, and effective, water softeners use an ion exchange method to reduce the hardness of the original water source. New 'non-ion exchange' systems are showing up on the market, but their effectiveness and viability are questionable. Hardness can't be reduced by a water softener without altering the water chemistry. These newer systems claim to change water chemistry, but don't claim to actually remove any dissolved salts. Therefore, they may not produce water suitable for orchid irrigation.

Minerals dissolved in the water create the hardness. A conventional water softener works to reduce that hardness by tying up those minerals with an ion exchange process that then keeps the minerals out of the water entering the house. The minerals usually dissolved in water that produce the hardness are a variety of ordinary salts, most of which include a bond of some metal with carbonate. When passed over a resin system containing sodium, many of these compounds give up their bonds, take the place of the sodium in the resin, and release the sodium into the water. This reduces the hardness. When the resin system "runs out" of sodium ions to exchange, a brine made from added salt renews it. But, the point is, this ion exchange process leaves behind high levels of sodium in the 'finished' water. If you are on a low sodium diet, you should talk to your doctor before using a softener. High sodium can be bad for you, and it is absolutely lethal to your orchids!

R/O Water

Water cleaned and purified by Reverse Osmosis, R/O, is becoming more common with the advent of small, self-contained systems. In fact, some orchid and plant supply companies have started marketing low output R/O units specifically for the purpose of irrigating sensitive plants. Some advertisements claim this to be the ideal source of water for the orchid hobbyist.

Reverse Osmosis uses pressure to literally push water through a membrane. The holes in the membrane are so small, dissolved salts and minerals are stripped from the water on the molecular level and filtered out. The concentrated minerals are flushed from the unit and discarded, leaving only very clean water.

But, while very "clean" water means no harmful salts or minerals, it also means there are no beneficial salts or minerals, either. The R/O system essentially removes everything! Orchids have to have nutrients and some minerals, called trace elements, in order to thrive. They might survive without enough trace elements, but they will never grow to their potential if they do not receive completely balanced nutrition. To correct for this situation, special orchid fertilizers are marketed for use with R/O water sources.

If the problem of balanced nutrition is solved, there are other problems with R/O that must be addressed. Cost is the obvious first consideration. There is the initial cost of the R/O unit, but there are also recurring costs for replacement membranes and even possibly de-scaling chemicals that may be needed to cleanse the nanofilter, depending on the quality of the source water used. If you are buying your source water, from a municipality for instance, that cost has to be added when considering the complete expense. Fertilizers formulated for use with R/O water tend to be more expensive; they have to contain more constituents. Finally, small R/O systems take time to produce the pure water, need some way to store the water, typically make relatively small quantities of water each day, and a spray tank or pump system must be used to irrigate your orchids.