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|Vol. 10(12), pp. 4-9||The McAllen International Orchid Society Journal||December 2009|
The idea of orchid "WANTS" was the subject (some time back) of a presentation of Mr. Weyman Bussey to an orchid society in I believe) Hawaii. The following article is a somewhat (and Dr. Russell would add a somewhy) altered version of the Bussey presentation, but the original idea of "orchid wants" was generated by Weyman Bussey, not this editor/writer! Your editor has only embellished on his idea, and added a few of his own.
Orchid plants may be compared to humans in that both have wants and needs. Most humans, however, due to being almost constantly bombarded by advertising, tend to confuse a "want" with a "need." For example, your editor, with some effort, may sell himself on the idea that he "needs" a new car or pickup truck. However, the family jeep has just a little over 355,000 miles on it, the pickup truck shows a mere 251,000+ miles. Both get good gas mileage, are not burning oil or making strange noises, and neither shows any other signs of vehicle senility. The jeep even had a new engine installed at around 306,000 miles. There's always the pessimist who bleats that "anything might go wrong," but your editor's seen that happen even to million dollar fighter jet aircraft with less than 100 hours of flying time. There are also two other considerations: one is the several thousands of dollars a new vehicle would cost, and the second is the "Bubba factor!" Bubba regularly gets vehicles for trouble-shooting, periodic, and preventive maintenance, and that kills a lot of vehicle problems before they're birthed! Sum total: your editor can't even begin to convince himself, much less his wife, on any real need for a new vehicle!
Do you really "need" a new orchid plant? Any self-respecting orchid lover will always want another one, but to really need one is a whole different bag of fish, and the same is true of orchids. There are things an orchid plant might want, and there are things an orchid plant will need, and the orchidist should keep both in mind! There's one thing more to keep in mind: there is no such thing as a "houseplant!" Some plants are more tolerant of the abuse and deprivation of certain of its needs by being kept inside a house, but all plants are native to an outdoor environment somewhere. Its native outdoor environment just doesn't happen always to be the same as where you live, so--for the plant to do its best--the orchidist has to make up for what's lacking inside a house. In short, there are things any plant wants and needs, and if these are not provided, it will not do its best! In fact, the plant may simply go downhill and die!
Whether you grow indoors, outdoors, or in a greenhouse, you need to learn how to adjust the five basic factors influencing the growth of your plants. These factors are all interrelated and by altering any one of these factors, you will be required to adjust the other four. They must be balanced and the key to successful orchid growing is moderation in all aspects. The solution is relatively simple: visualize your personal wants and needs, and apply them to your orchids! If you lump Air, Temperature and Sunlight together, we can call them climate. What climate do you like? Face it, when you are comfortable in a climate, your orchids are comfortable. If you allow your plant's ambience to become so hot you can't stand it, most likely your orchids can't either! Remember their "WANTS": There's one for each finger on your hand:
Water - Quality, quantity and frequency.
Air - Quality and movement, for gas exchange.
Nutrition - Fertilizer, vitamins and alcohol.
Temperature - They do not use clothing!
Sunlight - The ENERGY that makes food.
Put each first letter together and you have WANTS. It's that simple. Now we'll break down each factor as far as time and space permits in this issue.
Quantity, amount: ONE INCH, is a good watering, but not applied in 30 seconds! Applied over 30 minutes or more it's great. It's like rainfall. It's refreshing. Fertilizers may be applied with each watering, but fertilizers cannot be applied with each refreshing.
Frequency: A GOOD WATERING might be every 4-14 days, depending on A,T and S (Climate). Refreshing may be as often as 3 times per day, just to wet the leaves and let them dry. Humidity in the plant's region should be above 50% if possible. If not, water more!
Water Quality: There's more to water than what's generally seen! Most water contains a certain amount of dissolved salts. These are measured in parts per million (PPM) or in the Electrical Conductivity available, and the plant grower should always get at least one complete water analysis. pH gives a measure of the water's acidity/alkalinity. If the water contains more calcium salts it will lean toward being alkaline (basic). If it has more sulfur or chlorine it will tend toward being more acidic. A pH of 6-8 is generally acceptable. In fact, orchids grown in pHs of 7-8 tend to have fewer disease problems because many diseases will not grow in these more-alkaline conditions.
Contaminants such as chlorine (e.g. city water that's been chlorinated), or calcium or sodium from water softeners are definite no-no things! Distilled water: Never use pure distilled water! The plant needs at least 80 ppm of "good" salts in its water, so remix regular water with distilled, at least 20 %. Rain generally contains 80 ppm's of good salts. It obtains these as the water passes through the atmosphere en route to earth.
Water is a very important factor, which may determine your success with any orchid. Quantities can be split into how much and when. Your water quality will affect greatly the amount of water you give with each watering. If your soluble salts are below 200 ppm then you will require less water, less frequently. Above 200 ppm, you will have to leach out the salts with larger amounts of water over a longer period of time during each watering and never allow the media to totally dry out. If it dries out too much, burning of the roots will occur due to the increase in concentration of salts. Regardless of the concentration of salts in the water, you should always water until it runs through the media and out of the bottom of the pot. Allow the pot to dry out between watering, unless you seek hydroponic roots. This will create problems for the plant if removed from the continuously wet conditions. The amount of time between watering will be determined by the pot size in relation to the plant size; the type of media used; the relative humidity in your greenhouse and the temperature. Where (the geographic area) the plants are grown will determine the type of watering that needs to be done, and personal observation is the best guide as to how often one should water. Let the orchids be your indicator. Give all of your orchids the same treatment and one should observe each new growth a little bigger and healthier than the previous one. If the contrary is observed, the situation will have to be analyzed and conditions adjusted to achieve the results desired.
AIR MOVEMENT is a must for all orchid species. When using high air movement, maintain high humidity! Moving air eliminates water logged conditions and also helps supply fresh gases for growth. Although people are generally daytime animals that sleep at night (exception: journal editors), plants work 24 hours a day! With proper daylight, they produce food which is consumed both day and night. They do produce oxygen during the day, and to do this, require carbon dioxide, which they also fix at night for consumption during the day. However, during the night they use processed carbon dioxide for root growth which also produces more oxygen as waste material. Constant air movement abets these gas exchanges. Not permitting a constant supply of air to a plant is similar to (although perhaps not quite as drastic) as an individual attempting to live with his head in a plastic bag!
There's more: Stagnant air is an open invitation to fungus growth! Plants generally don't want to be watered late in the day. Rose growers have known this for years! Water a rosebush late in the day and then look at all the little black spots on the roses the next morning. This is a fungus called botrytis, and it not only disfigures the flowers, but damages both flowers and plant parts. If it does this outdoors, it doesn't take a rocket scientist to deduce that this problem gets magnified in a closed-in greenhouse with relatively little air movement!
A plant's general cycle may be summarized as follows:
24H2O + 24CO2↑ → 2C12H22O11 + 25O2↑
(24 molecules of water + 24 molecules of carbon dioxide gas becomes (with sun-energy) 2 molecules of sugar and 25 molecules of oxygen)
Nutrition essentially boils down to fertilizing, which is feeding the plants the chemicals they need. Chemicals? Of course! Plants "feed" via two pathways: through the roots or the leaves (also stems). Animals ingest food and then digest it. Plants absorb certain necessary nutrients, and manufacture others, hence some nutrients need to be water-soluble so they can be taken up by the plant. In nature, epiphytic orchids attached to a tree obtain these needed minerals through windblown dust, debris, bird droppings and the like caught on the tree or in their vegetative parts, and absorbed by their leaves and roots. This sounds like a catch-as-catch-can system, and it is. That's why one doesn't see a plant flowering in the wild that compares to a similar-sized one in culture that's well grown and well fertilized. Good plant growth doesn't take much fertilizer, and too much can be just as bad as none at all!
Plant fertilizers are chemicals (salts), and normally the commercially available ones also contain a very small amount of trace elements (micronutrients) as well. Bussey advises that for those familiar with fertilizer calculations, 100-200 ppm every fifteen days of N -- P2O5 -- K2O in the irrigation water will be sufficient, or this can be supplied with every watering for greatly increased growth. He goes on to say that for those not familiar with fertilizer calculations, simply dissolving one (level) teaspoon of 20-20-20 per gallon of water and applying it to your plants once every two weeks will work (If the formula used is 10-10-10, then use 2 teaspoons, etc.).
Your editor modifies the above advice and uses 20-10-20. Orchid watering involves the pots (and mounted plants) draining considerably, and this translates (over time) to fertilized water draining from the greenhouse into the pasture, and phosphorus tends to be retained in the local soils rather than drained away with the rains. the result is that unless one has phosphorus-loving plants in the greenhouse-drain area, one eventually sees "phosphorus burn" on some of the grasses and other vegetation. In an urban environment, such water is merely transported into the population's sewage system. However, in a "country" environment one is living not only on the land, but with it, and what is one to do with the phosphates that are drained from the home's washing machine onto a section of somewhat remote from the home? Local climate permitting, banana plants are phosphorus lovers, and draining the wash water to the banana patch can use the phosphorus to good advantage! Result: it's now early December, and as the first frosts (and freezing temperatures!) begin, a stalk or two of ripe bananas is still being harvested! By January, the banana grove will look terrible from the frost and freeze damage, but will show new growth by mid April.
Bussey adds, "Do you take vitamins? I recommend "Superthrive" with every fertilization, especially between March and September. One to four drops per gallon, four in the spring and summer and one in the fall." Your editor has not jumped into this additive, but has heard from orchid growers who swear by it, and others who swear at it.
Another Bussey-recommendation is offered verbatim: "Adding the equivalent of one cc/gal (1 teaspoon in 5 gallons) of 180+ proof alcohol to every gallon of fertilizer water applied, will double growth, pop all dormant eyes, extend the life of organic media, quadruple your root system, and kill bothersome insect pests. Alcohol is an adjuvant, give your plants a Happy Hour!"
Your editor's comment: why might this have any merit? A local (tree) nurseryman suggests the addition of alcohol (grain alcohol, not the denatured rubbing stuff!) dissolves a certain amount of the waxy cuticle on the leaf and thus allows foliar fertilizers to be more readily absorbed. Draw your own conclusions, but do so after conducting some fairly well controlled experiments.
More Bussey advice:
"The delivery system! It may sound like rocket science, but it's just the placement of the fertilizer on the plants! Hose-ons, which attach to the faucet with a feeder tube on its side do not work, unless your hose is abut 15 feet long. For fertilizing I recommend the Gilmour end-of-the-hose sprayers with 5 or 6 gallon capacity. They cost $3 to $5 depending on where you get them. I think liquid feeding is the only way to go, unless your plants are outside and it rains on them every few days. If this is the case, then apply lightly, 10+/- granules of "nutricote," every 3-4 months per 4 inch pot. That is a pinch, and for every inch bigger in pot size add another pinch with each pinch spread out over the pot; not deposited in a heap.
Try to fertilize once a week, except that on bright, hot, sunny summer days it may be done twice. That usually should be the only heavy watering! Any remaining is used to maintain humidity and lower high day temps, which may be necessary as frequently as four times a day. Looking at the plants one can tell when they need more water, but this isn't on any real schedule other than a one minute sprinkle timer-programmed at 1:00, 3:00 and 5:00 pm. In southern Texas average summer daytime temperatures may reach 110o F.; much higher than South Florida., and plants requiring cooler conditions will have to be grown in a cool house.
When fertilizing, water the plants within 30 minutes before doing so. If there is too much fertilizer in the water, the plants have already made their initial absorption of plain water and they won't burn because they are sucking up volumes of salts. This pre-watering also breaks the surface tension on the surface of the roots and leaves, and allows the fertilizer water to come into contact directly with the surfaces. The plant will then select which nutrients and quantities it needs to absorb. Even if Nutricote, is used, one might also consider a supplemental watering with alcohol and organic micronutrients. The recommended fertilizing regimen is once a week between 9 and 10 in the morning."
Temperature is of major concern in successful orchid growing. Daily as well as seasonal temperatures are important. For a hybrid orchid, one should have a good ides of where its ancestors came from, and in the case of a species orchid, where it came from. In any case, knowing from where the plant or its ancestors originated can offer clues to the general culture in which it might do its best.
The orchids of Mexico are concentrated between latitudes 14 and 24 degrees north. There exists an average difference of 7-10 degrees C between summer and winter temperatures. Apart from this seasonal difference, we have the major division of species by temperature derived from elevation. For every 300m rise in elevation there will be an average drop of 1° C. Expressed in feet, the normal adiabatic lapse rate is 2° F. per thousand feet. Combining the effects of elevation and seasons, considerable extremes may be obtained. These extremes are what make Mexican species more tolerant of greenhouse conditions in higher latitudes and somewhat easier to grow than species collected near the equator. However, one must adjust fertilization and watering frequencies to go with growth cycles. Water and feed heavily starting around mid-February and ending in September. This is the time the natural sunlight is peaking along with temperatures, which is the time to take advantage of this free energy and grow those plants at their maximum. For simplification of temperature requirements, most growers divide genera into the following categories:
(to be continued)