Phalaenopsis Journal Third Quarter 22(1&2) 2012 | Page 8

photosynthesis . Deficiency symptoms include wilting , stubby roots , chlorosis ( yellowing ) and bronzing . Flower scent may be decreased . Nickel ( Ni ) is required for iron absorption . Plants grown without additional nickel will gradually reach a deficient level at about the time they mature and begin reproductive growth . If nickel is deficient , plants may fail to produce viable seeds . Sodium ( Na ) is involved in osmotic ( water movement ) and ionic balance in plants , much as it is in people . Cobalt ( Co ) is required for nitrogen fixation , so a deficiency could result in nitrogen deficiency symptoms . Silicon ( Si ) is found as a component of cell walls . Plants with supplies of soluble silicon produce stronger , tougher cell walls making them more heat and drought tolerant . There is also some evidence that silicon plays a role in the prevention of fungal infections in the case of tissue damage .

How Much Fertilizer Should Be Used ? Like pretty much all other factors of orchids growing , there ’ s no set answer , and “ it depends .” As a general rule , fast growers in bright conditions require more food than do slow growers in heavy shade . Similarly , those trends can apply to your specific lighting conditions . A grower in Florida has more light flux than we do here in Pennsylvania , and we have more than someone in Canada , so the food requirements decrease as you move north . That analogy may be applied elsewhere as well , for example to HPS versus fluorescent lighting . While that may suggest general trends , it doesn ’ t provide the quantitative answer we need . Many professional growers base their nutrient concentrations on the amount of nitrogen provided to the plants , with 100 to 250 parts per million ( ppm ) N being common . It appears that in epiphytes , the plants ’ demands for potassium and phosphorus appears to be REALLY low . At First Rays , we shoot for roughly 50-75 ppm N , based to some degree upon the learning with animals ( including humans ) are healthier and have greater longevity with a limited , but complete diet . Why not plants , too - especially ones that come from notoriously low-nutrient environments . We settled in on that level because of our varied collection : Vandas may like more and Phrags less , but we ’ re way too busy to cater to the individual , so we came up with an average and feed at that rate at every watering . Others find that increasing the concentration is beneficial , but irrigate with fresh water periodically to flush residual minerals from the medium . You can determine the amount of fertilizer to use based upon the formula of the blend you have using the simple calculators posted on our website : http :// www . firstrays . com / fertcalc . htm . Additional culture information can be found on the First Rays website , http :// www . firstrays . com / free _ info . htm .

8

IPA DONATIONS

IPA gratefully acknowledges gifts from the donors listed below . Their generous and heartfelt donations help make the services of IPA , including the quarterly journal Phalaenopsis available to the alliance ’ s worldwide membership .

Platinum - $ 5,000 or more Gold Medal - $ 1,000- $ 4,999 IPA Region 12 ( Southeast ) Dr . & Mrs . Olie Garrison The Robert Gordon Family in Memory of Robert J . Gordon

Silver Medal - $ 500 - $ 999 Karen Armstrong IPA Region 13 ( Piedmont ) Houston Orchid Society

Bronze Medal - $ 250- $ 499 IPA Region 3 ( Northwest ) Supporting Donations - up to $ 249

Robert Bannister George Vazquez IPA Regions 9 & 10 ( Midwest ) Maynard C . & Helen V . Michel Mr . Louis Barnaire David ( Mike ) Ingle Ray Barkalow Robert Fuchs & M . Coronado Alvaro Rosales Julius Ellison Jim Pearce T . Lyn Pearce Ron Melander Janice Mazur Judi Ream

Third Quarter , Vol . 22 ( 1 & 2 ) 2012 - Phalaenopsis