The Orchid Garden

Sphagmum and Fertilizer

Question:

*SNIP!* I’ve been hooked on orchids for about 2 1/2 years now and because of several moves have not determined the best medium for my phals yet.  My question is how to fertilize my phals that are potted in sphagnum without burning roots and growing lots of algae. I grow under fluorescent lights in a sunporch during the winter, use rainwater and Dynagrow 7-9-5, though sometimes they get a cocktail which includes Peters 30-10-10.  Is the urea in the Peters the problem?  In the past, I had more problems with root tips burning, that isn’t happenning at all now but the algae does develop. One solution that did not work for me was to put a layer of charcoal below the top layer of sphagnum.  Thanks in advance for suggestions,                                        John Whistler                                Will it really snow again this weekend                                in Chesapeake, VA?  75 and overcast today

*SNIP!*         Hi, John!         I like to grow in sphagnum myself, but not pure- there are some problems with growing in 100% sphagnum (like burning, I have found, along with premature decomposition). My favorite mix (and anybody who has been on here for more than a few months can probably say it in stereo along with me) was OFE’s old orchid mix with… well, most everything in it. They discontinued it, as cork nuggets went sky-high.         So, I went and bought a bunch of plaques, and gave myself blisters cutting the stuff up with a little knife, but- hey! I got what I wanted. So, when I play a little tune for my Phals, it goes a little something like this…         A handful of sphagnum (the long-fiber stuff, pref. New Zealand)         A handful of cork         Equal parts of chunk perlite or rock-wool (something inorganic that is big enough to keep from falling out of the drain holes in the bottom), to season (between 1/2 handful and 1-1/2 handfuls)         As much orchid bark as you want (1/2 to 1-1/2 handfuls).         Lots of charcoal, to season.         Some people exclude the charcoal, citing how it will tend to accumulate the salts on the outside of the nuggets, inducing root burn. I have never experienced this, but some people swear it occurs.         Then, mix it all up. If you have problems with burning, put the sphagnum at the bottom, fir bark on top. If you have an older Phal that is growing like a weed, but no burning problems put the sphagnum on top. And here is why….         Most peoples Phals die as the result of dehydration. The ACTIVELY GROWING ROOTS appear at the base of the plant- right under the newest pair or trio of leaves, commonly ripping other leaves in order to get out. These poke on out, and if there’s no moisture or moist air, they perish- dried out by the sun and wind.         BUT… if you carefully pack the base of the plant in sphagnum, being careful not to keep any of the leaves too wet for too long when you water (just so the new, adventitious roots stay moist for a few minutes each time you water), YOU’RE SET!         Your particular problem (watering with rainwater, but STILL getting root burn) can be attributed to one of two things.         1) You’re fertilizing too often. Most growers that I know of use the fertilizer at 1/2 strength, once per week or two AT MOST. Anything more than that causes the bio bugs to go into overdrive, and eat the media like my newphew sucks down M&M’s. It leads to massive media decay and, at worst, root rot and (if you haven’t a strong stomach) nausea when you repot.         Ewww.         Me? I fertilize once a month, but water every week with a vitamin suppliment (I won’t name names, but it’s SUPER and my plants THRIVE on it). Of course, I live in the desert (Socorro, New Mexico), and the heat may have done something to my brain.         2) I always had problems under lights with low humidity. So, my plants would be bone dry after about 12 hours immediately after watering. No joke! The heat and the low humidity just dried them out. So… the salts would accumulate every single time you watered. The most basic solution to ANY kind of salts accumulation is to FLUSH with lots of fresh water, each time you water. Put enough water through so that the entire pot is flushed. And water *just before* the plant dries out, so the salts haven’t all hit the solids stage, and are therefore less soluble.         The *real* trick is to water, flushing the pot, then water again about 6-8 hours or more later, when the hard salts have gone back into the solution phase; when you water again, you then flush ALL that stuff out.         Aren’t I sneaky? *grin*         And, if you’re really cheap about fertilizer, and don’t have a problem with root burn, try this: water your plants. The next day, go around with a mist/spray bottle full of fertilizer soution, and spritz a bit into the pot; it distributes better, and you’re not wasting $$$ on fertilizer flushed down the drain. *grin*         Hope this helps.         -AJHicks         NMTech

Response:

I’ve been hooked on orchids for about 2 1/2 years now and because of several moves have not determined the best medium for my phals yet.  My question is how to fertilize my phals that are potted in sphagnum without burning roots and growing lots of algae. I grow under fluorescent lights in a sunporch during the winter, use rainwater and Dynagrow 7-9-5, though sometimes they get a cocktail which includes Peters 30-10-10.  Is the urea in the Peters the problem?  In the past, I had more problems with root tips burning, that isn’t happenning at all now but the algae does develop. One solution that did not work for me was to put a layer of charcoal below the top layer of sphagnum.  Thanks in advance for suggestions,                                         John Whistler                                 Will it really snow again this weekend                                 in Chesapeake, VA?  75 and overcast today

Response:

j jI’ve been hooked on orchids for about 2 1/2 years now and because of jseveral moves have not determined the best medium for my phals yet. jMy question is how to fertilize my phals that are potted in sphagnum jwithout burning roots and growing lots of algae. jI grow under fluorescent lights in a sunporch during the winter, use jrainwater and Dynagrow 7-9-5, though sometimes they get a cocktail jwhich includes Peters 30-10-10.  Is the urea in the Peters the jproblem?  In the past, I had more problems with root tips burning, jthat isn’t happenning at all now but the algae does develop. jOne solution that did not work for me was to put a layer of charcoal jbelow the top layer of sphagnum.  Thanks in advance for suggestions, j                                        John Whistler j                                Will it really snow again this weekend j                                in Chesapeake, VA?  75 and overcast j                                today John, If you’re keeping your phals a bit on the wet side and not flushing the pots occasionally, I’d be pointing my fingers at the 30-10-10. Wetter Sphag is much more likely to grow bacterial cultures than drier and you’ve probably got nitrogen overload around the roots. For future reference, make sure you keep plenty of air space around the roots when using Sphag. As for the algae, if you’ve got algae on the surface put that charcoal right on top. If you’re using clear pots and are worried about the algae on the inside surface, it’s not really a consideration. The algae can only penetrate so far into the media before it runs out of light, so as far as any impact on the plant goes, it’s probably negligible. On the plus side, it probably assists in gas exchange within the pot. A nice bonus. -Rod- Rod & Susan Venger, Venger’s Orchids Homepage address http://www.usa.net/venger/ Listings Available – Email us for your copies Order Line 1-800-483-6437 —

Response:

- Hide quoted text — Show quoted text – Newsgroups: rec.gardens.orchids I’ve been hooked on orchids for about 2 1/2 years now and because of several moves have not determined the best medium for my phals yet.  My question is how to fertilize my phals that are potted in sphagnum without burning roots and growing lots of algae. I grow under fluorescent lights in a sunporch during the winter, use rainwater and Dynagrow 7-9-5, though sometimes they get a cocktail which includes Peters 30-10-10.  Is the urea in the Peters the problem?  In the past, I had more problems with root tips burning, that isn’t happenning at all now but the algae does develop. One solution that did not work for me was to put a layer of charcoal below the top layer of sphagnum.  Thanks in advance for suggestions,                                    John Whistler                            Will it really snow again this weekend                            in Chesapeake, VA?  75 and overcast today

For whatever may be worth. I use special media which looks like dirt and styrofoam.  I get it from Orchids and Ferns here in Houston.  That is what they use for all their orchids.  Phals do great in it.  The best thing is that it will not decompose or turn ’sour’.  Also, you can use regular orchids fertilizer instead of high first number due to nitrogen depletion by bark. Living is like licking honey off a thorn

Response:

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