The search for the wondrous orchid fertilizer continues. There is over on the gallery a picture of my B. nodosa. Every summer when growing conditions are to its liking it blooms. It also tries to bloom sometimes in winter and the flowers abort and no amount of fertilizer then (wondrous or non wondrous) will make any difference. Growing conditions then are just awful (for B.nodosa).

Now despite all these trials that tell you that so and so fertilizer is just great the problem that i see is that everyones growing environment is different, light, temperature. different water quality, different potting mixtures and methods . I think i'm trying to say that these growing conditions might have very little in common with those used in trials. So the fertilizer manufacturer has a a little bet each way and and gives you a fertilizer that will perform well in average conditions.

I think we're throwing the baby out with the bathwater here.

John

Please explain.

Well ok. I think good orchid culture happens incrementally from a gradually expanding knowledge base. You improve this little bit, then that little bit and through it all you're learning, hopefully. To suggest what people are already doing is good enough because they probably have crappy light anyway isn't expanding anything for anyone. In my opinion.

For anyone who may be interested, the article is written by a couple, Marvin and Rene Gerber, who have been growing orchids for 31 and 33 years respectively. They are both AOS judges. Marvin Gerber has served various offices in the AOS, including Executive Vice-President from 1994-96, and AOS President from 1996-98. Together they have over 100 AOS quality awards for their plants including some of their own hybrids. It relates what they learned from certain well-known and well-respected professional growers in their quest to become more knowledgeable about orchid nutrition. The title is, "Orchid Growing 201".

The side pane, from which I drew my comments in this thread is entitled "A Short Course in Nitrogen." It is written by Ron McHatten, Phd, and AOS Director of Education.

John

I'm confused and i have been growing orchids for 100 years. One old time grower told me he had never used any fertilizer that would make the plants "jump out of the pot".

Looking at the label of my "water soluble orchid plant booster"
NPK 12-12-20 and yes it is twice as expensive as say Miracle-Gro all purpose plant food.

I use this stuff most of the year except in summer months when horror upon horrors i use Miracle-Gro all purpose plant food.

Getting down to the nitty gritty. Total Nitrogen (N) 12.2%
Nitrogen (N) present as Nitrate Form 4.3%
Nitrogen (N) present as Ammonium Form 3.9%
Nitrogen (N) present as Urea 4.0%

Interesting that the dilution is 5Grams in 5 litres of water for most orchids except Phalaenopsis where the recommended dilution is 5Grams in 10 Litres of water.

As i said in my post above the fertilizer manufacturer cannot control what happens in the customers growing environment so they try for a middle of the road formula.

So, you could provide a better fertilizer for your growing conditions by analysis of your water supply and the PH of your potting mixture. But i question the benefits and cost of such procedures.

By the way, the horrible conditions for B. nodosa in winter are due to the stinge bag writer not supplying enough winter heat at night rather than lack of light.

Now waiting for a boffin (Scientist) to tell us us all why most fertilizers have the three forms of Nitrogen present.

I'm not a real boffin but I play one on the Internet. This Pretenders take on your question, Arthur, is as thus:

The article I linked in my earlier post stated thus: "Some plants prefer the ammonium form of N, and others like to take up nitrate first. The majority appear to show no real preference, or research has not been completed that shows a preference exists." Well, if you were a general purpose fertilizer chemist charged with creating a formula that will show results in as wide a population of growing plants as possible you would likely hedge your bets too, thus ensuring that no 'chid is left behind by the formulation that you release to the public. Privately, you might have your opinions on the matter and seek specialist formulations that promote a particular form of nitrogen source but that would be your responsibility and to pursue your ends on company time might earn you a reprimand. Keep that in mind. And speaking of mind, would you mind if I left character for a moment, um, John? Where is the love, man? I'm feeling a little hostility here. I didn't mean to dismiss your post, only to explain why possibly the issue hasn't exactly set the orchid world on fire. Please put that emoticon thingy back in your signature... thanks Arthur.

H

Needless to say (but I'm gonna say it anyway), I haven't been growing orchids for 100 years; but Arthur has an excellent point (if I understand correctly--please forgive me, Arthur, if I don't): In the fine tuning of fertilizing orchids, there comes a point of diminishing returns for most growers.

Hail to those who study and test to develop the perfect fertilizer. And to those who run controlled studies on the usefulness of fertilizer ingredients. Growers who pay attention can benefit from their work. I suspect, however, that most orchid hobbyists are unwilling to pay an arm and a leg for each year's "perfect" formulation.

And hail to you "confused (I doubt that)," but experienced, or boffin pretenders, who take the time to share information with facts, figures, and humor (!) in the intelligent and amicable discussion of orchid culture. You enrich the forum.

"..that no 'chid is left behind...." :)

I Love this forum!

Sweetcicely

As I said before, the point is being missed. None of this is about the perfect fertilizer. It's about increasing our understanding of what orchids respond to and why. But hey, if no one cares then far be it from me.

Howard, I don't believe you've done this forum any service by your inexplicably negative response to this subject matter. To actually state that you'll get back to everyone after you've done a few web searches is an absurd response to a broad-based article written by individuals who indivdiually have a large bank of experience and knowledge to draw from, let alone the cumulative experience reflected in the piece. Where's the love? My love is honest and active inquiry. I thought I had some company here. My mistake.

John

John, i do have access to a scientist. Asked him about the Urea thing and he told me that at normal growing temperatures Urea is quickly converted to a form that the orchid can use.

Said scientist could also tell you exactly how much and what fertilizer to apply to a cotton crop for maximum yield once climate, soil and water data is known. This knowledge comes from numerous trials and is available for plants grown in commercial quantities.

The problem with orchids is that the home grower has an environment that may bear no relation at all to that of the advanced expert grower and that is why this forum exists.

Typical example. I grow Phals on windowsills. That is about 17 feet of windowsill length and of course, I am growing too many kinds and perhaps the fertilizer, watering routine and potting mix are unsuitable for those conditions. There will be a very slow evolution as species and hybrids are discarded or die and i am left with the ones that grow well and flower.

Contrast this with a Phal. expert who has two purpose built large Phal. houses that are set up specially to grow Phals and nothing else. No wonder he wins Champion Phal at various open to all shows in the spring showing season here.

So, when the Phal guy comes to talk at the local Society he has to set his talk at the level of a windowsill indoors grower with no lights because that is the set of conditions most members are blessed with.

After growing for twenty years and not growing for almost as long, I have come here to learn. All I can say is that this is "deja vu all over again"!

Laurel

Well, to return to the original subject - I think - it's gone so far afield I'm not sure what the original question was. I currently base my feeding program on the Fender's Flora newsletter entitled "A Feeding Program for Your Orchids" or something pretty close to that title. It's only 1 page, so I recommend reading it from their website, but the backbone idea is small dose applications of Dynamite 13-13-13 (a time release fertilizer) 6 months apart and supplemental feeding during the spring/summer/fall. It's easy and effective - I can see a difference in my orchids from about August when I started the first few on this program. It works for me because I don't like to fuss. We'll see if I get to the supplemental feeding stage, but at any rate they're getting fertilized more regularly than they were before, and seem to be responding.

Thanks Arthur. I appreciate your checking with your scientist. I sometimes find when two authorities disagree on a point, that when the discussion is carried through they often end up with correlated statements. For example, "quickly" is a relative term. Whereas the statement, "urea must first be converted by soil organisms into nitrate, a process that can take several days" seems a bit more on point. There are three specific reference points here. First "soil organisms" (are their soil organisms in standard orchid mediums, and if so which ones and to what extent?) Second, urea converted into nitrate (oh, so orchids can only absorb nitrogen in nitrate form why not give it to them that way in the first place? and by the way are orchid roots evolved to absorb nutrients quickly given their special adaptation as epiphytic organisms?). The third is "several days" (depending on watering/feeding practices, that could be a lot of nitrogen down the drain). Theres a lot of information in that one sentence.

The second concern is that the conversion process significantly acidifies the pH of the medium. Since many of us have found non-organic mediums to be attractive choices, and since these have no buffering capacity against an acidifying agent, this would also seem pertinent.

Arthur, I take your point that not everyone really cares about this stuff. On the other hand, there are several advanced growers that participate in the forum who may be interested and others who may simply be intrigued. Certainly enough that would justify the imparting of nutritional information on a fairly basic level, which this was meant to be, without having to battle other members as to its relevance. That is all I take issue with. I cant believe how much energy Ive had to spend defending the relevance of this topic which is far different, and far more exhausting than the topic itself!

I see absolutely no difference in a small hobbyist and the large professional grower when it is a matter of ensuring that your plants are receiving the nutrition you are intending for them. Granted some just want good enough. Fine. And granted, it could be a bit much for beginners. But even beginners would benefit from at least acquainting themselves with nutritional options, and even considering a solid, not particularly complex, nutritional program for their plants that is a cut above what you can pick up in Walgreens. It all goes into the mix.

One last point the authors of the article are home growers, not professionals. They simply surmised that they could do better for their orchids than the standard 20-20-20 thing that most people accept as sufficient. So they talked to professional growers and after having implemented a fresh regime tailored to their needs as smaller growers, have seen marked improvement in their plants. In itself, this could be dismissed as subjective wishful thinking. But when there is a correlation between perceived results over a period of time and long accepted-nutritional practice among those whose livelihood depends on healthy, performing plants, its probably worth a gander.

John

"Well, if you were a general purpose fertilizer chemist charged with creating a formula that will show results in as wide a population of growing plants as possible you would likely hedge your bets too, thus ensuring that no 'chid is left behind by the formulation that you release to the public."

To quote howarda, I also like to hedge my bets. As a fertilizer chemist puts three types of nitrogen in his formula to cover all bases, I alternate my fertilizer formulas. I don't limit my fertilizing program to one or two particular types of nitrogen knowing that possibly some orchids prefer one type over another and without knowing which ones do, I would inadvertanly be excluding some. Rotating different types of nitrogen makes sense to me.

It seems like the debate over nitrate, ammoniacal and urea nitrogen will go on forever. I could be wrong, but my understanding of what the article in the AOS really meant was that orchids don't really need lots of nitrogen simply because someone once decided that the degrading bark uses up lots of nitrogen and the plant would therefore be deprived of nitrogen if enough wasn't used. In reality the extra nitrogen only helps the bark to deteriorate faster.

Please let this thread die as you have already run off the original poster and have me wondering what's up here. I have a background/degree in biochem and a longtime relationship with orchids, in and out of greenhouse, and don't get this contentiousness at all. Some of you might know more than others but how does the direction of this thread help the original poster? In any forum there are people of all abilities. This does not give us, as participants, carte blanche to ignore other posters or to discredit individual successes or opinions. In my opinion the "window sill growers" have given great advice and support to the original poster. If you want to make fert theory/research a debate, then why don't you start a new thread? In this case I might have participated (that's if you could promise to be civil). Otherwise, it's almost Spring, I have a farm garden in addition to orchids, and it's time to collect manure elswhere.

Thank you for acting as moderator and thank you for being so civil. Love "it's time to collect manure elswhere." so clever and so rude.

After a lot of interesting, if sometimes contradictory reading, it seems to be generally accepted that conversion of urea into ammonia nitrite by hydrolysis and nitrite into nitrate by nitrification is the roadway for urea to be useful for any plant. The sources I read, which have no direct connection with orchids at all, generally agree that these processes occur before absorption by the plant and are dependent upon bacterial and microbial action in soil. Since it seems doubtful that these would be present in orchid potting medium, it also seems doubtful that urea is an efficient source of nitrogen for orchids, even if as some sources state, a relatively small amount of urea and ammonia can be absorbed directly by the plant. I realize that this is not "fresh" information, but I have found these central ideas repeatedly contained in the scores of different sources I've perused over the weekend.

As well, even if urea is converted to ammonium nitrite which in turn is converted to nitrate by oxydation, the process has an acidifying affect on the medium, which would not be welcome by most epiphytic and semi-terrestrial orchids. Yes, a buffer could be used but who is that in love with urea?

Soooo, even in spite of the annoying marketing practices that tend to make everyone cynical about fertilizers in general, the balance of information that I've been able to absorb seems to point to the advantage of a nitrate-based nitrogen source. Urea free? No, why bother. But a heavily urea-based fertilizer intended for soil growing, acid-loving plants? I don't think so.

I'm just going to make sure that the product is substantially nitrate based for optimum efficiency. I've read good things about Peters Cal-Mag, which maybe now is Jack's Cal-Mag. And I'm going to look into a micro-nutrient product called S.T.E.M. to use as an additive.

Sorry for the slight hullabaloo. It's clear that the thread has gotten away from the original poster. But it is entitled "ferts" after all, and it isn't nearly as flamey as a multitude of other threads I've come across here over the years - some quite recent. And, finally, hopefully some of this will end up as food for thought as well as for orchids.

John :>)

Have enjoyed the point/counterpoint and picked up some thoughts to mull over for my conditions. This is the kind of thread that I have to save for rereading and future reference.
Thanks!
Jan

arthurm-
You're kidding right? Must be a cultural/gender schism here to call me "LOVE". How condescending=sexist=(c)rude and disrespectful. I might be willing to chalk it up to the fact that you've been growing orchids "for over a hundred years" as you have previousley stated. Me as a moderator? No thank you. Those were the days of the old Compuserve fora. Negotiator, facilitator and general ass kicker? Yes. Please feel free to email if you want to continue your rant, otherwise...
Cheers,
Laurel (laurelburrows@mindspring.com)

P.S. John...thank you for your sensibility in a storm. I have enjoyed seeing the info presented although, as previously stated, I see nothing new that was not known twenty years ago and there were several "regulars" who tried to offer support and good advice to Deirdre. Hopefully she will take their advice. The rest reaffirms every ego of the amateur/expert. We can all go on line for that, but it is good to do research and share and help those committed to learning more. Perhaps a thread that could share the above would be beneficial. Don't try to pass this off as serious academic research unless you can provide the stats to back it. There are many behind us and ahead who can teach us if we open our minds. I would like to see as much current research as possible, but more importantly, I'd like to see as many beginners learn the ease and joy of growing without tryng to add smoke and mirrors. I didn't think my knowledge re:ferts (which is not original to anything mentioned here) would help the average grower or have been appropriate to this thread. If you could think about your experiential growth in becoming an orchidist, please (and I'd like to say this without being slammed) be sensitive to the new hobbyist as their interest has got to be the source of all the new and easier to grow orchids we have today.

To Deirdre, and those new to orchid growing, who ask questions, please keep on asking as, I can assure you, no one has all the answers.

Thanks, John I do find the article interesting and would like to read it. I have had problems with fertilizers in the past and over the years developed a system which works for me. I would be interested whether they mentioned what type of water they used - tap, well, RO?

pH plays a large role on how fertilizer is utilized and broken down. I have used urea nitrogen for years with good results. I've always had a problem with the argument against it.

I did not want to get involved in this argument because I grow on trial & error. I have conditions which are different from other growers and I have to play with how I feed and treat my plants to fit those conditions. I have no scientific knowledge of the 'rhyme or reason' why some things work for me and others don't.

Inert media, pots, baskets,etc. can, and will grow bacteria which helps convert urea and nitrates. I have had very good results using urea especially on dendrobiums. I never could figure out why. I think I know now, but I do think another thread on fertilizers would be a good thing. I would suggest getting your water tested before making major changes with your fertilizers. Sometimes 'what ain't broke'....

This is a very interesting topic which deserves to be explored. I don't think it's beyond the realm of new growers. Anyone who has gardened for a few years has some basic knowledge of how fertilizer works. People who have never grown anything before need to learn.

Jane

This really has been an interesting and enjoyable thread.

Deirdre received quite a lot of helpful advice, specific to her questions, early on. The discussion that followed is full of thought provoking, on-topic information for all who care to read it, whether experienced or not.

I appreciated John's digest of an article that many, here, may not soon see, unless they are subscribers. I also appreciated the ensuing discussion of the article's findings. It didn't seem particularly contentious to me. (Having no idea of the forms or proportions of nitrogen that I was feeding my orchids, I had to run and get the container to read it!)

Laurel, far be it from me to put words in Arthur's mouth, but I truly think that you have mistaken the beginning of his comment on your manure collection as a term of endearment. I think he simply left off the personal pronoun: '[I] Love "it's time to collect manure elswhere." so clever and so rude.'

Sweetcicely

Here's a new one to throw into the mix.

We all live by weakly weekly, well at least most of us do.

But...

At the orchid show I was just at we were discussing this and realize if a fert. is designed for orchids it is already diluted and should be used at "full" strength.

Orchid fert. is more expensive because urea based nitrogen is cheaper, and why it is used more widely and in more cases can break down in soil and be available. Orchids live in trees (mostly) get their nitrogen from animals over head (ammonia) and plant matter breaking down around them (nitrite).

I always go back to their natural culture for ideas.

I maybe way off and wrong, but the "right" way does not always work.

Jane, your point about water quality is of course well-taken. I'm sure that what ultimately works best is whatever the grower feels is yielding results.

As for trying to pass anything off - if I've conveyed that, it wasn't my intention. I do believe that there is quite a lot going on in some heads that has very little to do with what they are reading here.

As for the fert. subject - I accept defeat. It's too nebulous to do what I had in mind, which was to develop a basic, coherent and not overwhelming synthesis that conveyed good basic knowledge to novices that went a little beyond weakly-weekly with whatever is easy to find. But as things are, that still seems to be decent advice. Either you skate on the surface of the issue or you find yourself swimming for your life.

At least I learned several new words!

John :>)

Just a bit more.
Question to Scientist. Would the Urea free fertilizer as discussed earlier be fine.
Answer "positively".
What about the Ammonium Form.
Answer. "generally it is the best form for plants, but at certain PH levels in the media it degrades into Ammonia and the benefit is largely lost to the plants.
Do they put the Urea form into the fertilizer to save money?
No!
So it all comes back to the fertilizer manufacturer hedging their bets and thank you John for raising the question. It made me do a bit of research and ask a few questions. It has also made me confident that the fertilizer i use is fine for my conditions.

So. How much more expensive is a urea free fertilizer versus a more conventional fertlizer in the USA?

Sweetcicely. Your interpretation is 100% correct.

I've looked at a few today - the much-touted MSU formulas - and about $6 a pound seems a favored rate in the US. But that's for small quantities. I'm sure larger lots would be cheaper.

John

John, FWIW, I have grown to like the MSU forumula. I use the one for pure water as I use RO or rain water (when its not frozen) and it seems to work gently on my plants. I sometimes use their Tap Water in Spring. I have never liked high N formula's, even during growth periods. Nitrogen can produce rapid growth which is weak. I like slower growth as I think it makes for a healthier plant.

Me is correct, you really shouldn't dilute the recommended amount. That is another misconception. I think it probably started as advice for new growers who tended to over-due a good thing. When I fertilize, I fertilize full strength or not at all. Always have without a problem. I do not fertilize at all in winter unless a plant is starting new growth. I never fertilize a plant in bloom.

There are so many different ways we all handle our plants and it comes down to what works best for our conditions and lifestyle. This is a very good thread and deserves a new post.

Waiting on you John -

Jane

John et al,

MSU formula is available in a 5 lb container @$14,
25 lb @$40

These prices were noted from the web site of that fella in PA whose name is verboten here.

--Stitz--

Oh c'mon. Pennsylvania? That's a lot closer than the source I was looking at. Any chance of emailing me the link, Stitz? I only had one idea as to whom you were talking about but I didn't know FRs was in Pennsylvania.

My tap water is very low alkalinity, has average TDS of 50(!) and a pH between 7.1 and 7.3. Really good. Calcium content is 5.4ppm and magnesiuim content is 1.2 ppm. But I don't know what that calcium content means in terms of what orchids need. I suspect it is low, but how low? WAY low, or sorta low?

When I know this I'll be able to take one more step in deciding among the MSU pure water formula (12-6-13-7-2), the MSU tapwater formula (17-9-18-4-*) and the 15-5-15-5-2 Cal-Mag.

I'm really leaning towards the Cal-Mag even though I can't find it in any quantity under 25 pounds. It's a bit less calcium than the MSU Pure Water Formula and is less highly buffered as well.

I used the MSU pure water formula for awhile and my fussy brachy paphs really complained after awhile. But I think pre-watering would probably solve that problem. The pure water formula offers 7% calcium. Just don't know if I need all that.

Also, the instructions included with the MSU formulas are 1/2 tsp. every other watering. I.e., 1 tsp. per month, just as I was thinking. Let's talk more about this.

John :>)

John,

I tried to email you through the GW Orchid Forum. I believe that my email was NOT sent.

Email me. I will share more info.

--Stitz--

Stitz, you have mail.

I ordered the MSU tap formula after talking to the man at Roberts Flower Supply, whose name, inexplicably, is Wayne. He was nice enough to have a short chat with me since I was armed with my city water report when I called. This in spite of his being in the middle of trying to shovel snow which at the time was at 8" and mounting. Nice man.

If he'd had the Cal-Mag I would love to have chatted him up about that. I'm still going to look for it. It's a fixation now.

John:>)

Thanks for the thread, everyone. Fascinating, esp. about using orchid fertilizers at full strength, which I've been doing.

From "the clash of titans" comes much useful information.

John & others, one of our OS members buys MSU in the large quantities and repackages it in 6-oz. containers and sells it at OS meetings. Makes a profit, plus pays for his own supply.

Early on, several sources said not to use urea-based ferts for orchids, so it's been Green Jungle (available locally, so no shipping) or MSU. Because I'm new, the subtleties of a fert working or not working aren't fine-tuned - too many variables still being adjusted.

Thanks, Whitecat8

Ah why not throw another variable into the mix. Well two I guess...

How do you apply your fert., when?

Some argue fert. will not be absorbed if you don't wet the roots first.

some say the roots will only take in so much at a time, so if you water first no fert may be taken up.

I am still undecided, I switch between soaking them in fert. infused water, and watering them first then spraying them with fert. water.

Good idea... are we going for a hundred?

Dr. Motes, premiere vanda grower here is S. Florida, strongly discourages watering first for exactly the same reason you state.

If you do semi-hydro you use half strength fertlizer which sits in the reservoir. Once a month you flush with fresh water to dissolve salts that might have concentrated.

But then, a lot of very successful growers here, go along with the watering first method. I wonder if they truly water heavily first or just mist to get the stomata (is that the right term?) to start to open?

Anyhow, I don't water first. Not as faithful with fertilizer as I would like to be so figure they need all they can get. I do often water in between fertiizing.
Jan

I personally never prewet, too much hassle and I don't think it matters in my situation. I water mainly with a watering can. I heavily mist my non-spagh based mounties, but use the watering can (after slight misting to help prevent run-off) on the ones mounted with spagh.

Bob

Have you ever written a long post and then hit "Return to Forum" instead of Preview. Auuuuugggggghhhhhhh!!!!!!!

Re: prewetting. My own understanding is that prewetting is especially helpful for orchids with sensitive roots like paphs. If you pre-wet, plain water buffers sensitive roots that may have become dryish between waterings from concentrated chemicals. When you follow with a nutrient solution, it effectively replaces the pre-water in the medium and nutrient absorbtion continues as long as the medium remains moist and ion exchange takes place (so they say). Not necessary with all orchids. I usually dont' pre-wet phals or catts.

I'm confused as to concentration that people are using now. It might help if people give the concentration of the fertilizer, the rate they use in tsp./gallon (unless they're using a proportioner), and the frequency. Maybe I'm under-feeding. Some of my phal leaves are kind've mottled. Older catt leaves are a little yellowish. Sounds like underfeeding to me.

So are people using 1/2 tsp. of a 20-20-20 (or equivalent) as a constant feed with one drench per month?

Thanks!

John :>)

John wrote:
"It might help if people give the concentration of the fertilizer, the rate they use in tsp./gallon (unless they're using a proportioner), and the frequency."

Good idea! Sometimes it is hard to keep it all straight.

I use Schultz Expert Gardener Orchid Food (pink, water soluble granules); 19-31-17; with all three kinds of nitrogen (urea being the largest amount); trace minerals included. Though calcium isn't listed, a statement at the bottom of the list says, "Potential acidity 920 lb calcium carbonate per ton" (which only confuses me).

I pre-mix, using the container-recommended amount - 1/4 teaspoon/gallon of (tap) water - to water Phals (very young and mature) and one Paph for all waterings, except a once a month flush to dissolve any accumulated salts.

I don't pre-wet, but do let the pot sit in a slightly larger container (filled with the solution) for 3-5 min. Since the ions are already in solution calibrated for orchids it is ready for uptake and should not burn. I've never had root burn or brown leaf tips.

Prewetting will buffer fertilizer solution, but it seems to me that, unless the pot is then soaked in the fert., prewetting will only serve to dilute the feeding.

About hitting the wrong button, John, you have my sympathy (yes, have done that - Arrgh). You can get back to and post your message, by carefully using the Back and Forward buttons. The message will still be there. Another fail-safe method is to copy your message before clicking any buttons.

Sweetcicely

John,

I use 3 different types of ferts on a rotating basis (Dyna-Grow GROW & Bloom and a third weird fert I pick up at a hydro store). I'm at work currently, and don't know the numbers off hand. I do about 1/4t ger gallon, don't pre-wet and water each pot very heavily with a watering can. With over 150 orchids, it got way too time consuming to pick up each pot and dunk, so I started using the can and watering them in place. I use non-fert water once a month to flush everything.

Again, with 150+ orchids, pre-wetting would also add significant time to my watering schedule. I don't pre-wet and 'hope' that it is not a major issue. I'm happy with my growth and blooms, so until more motivating evidence arises concerning advantages of pre-wetting, I'll stick to my current regimen.

Can you tell I do everything I can to not become a slave to the 'kids -), when they start to control me I begin to feel like they are becoming a burden, then I start ignoring them and they and I don't fair well.

Bob

Ok, this is sounding nice and familiar now! With 1/4 tsp. per gallon I wouldn't worry about prewetting either. Seems like some others are using higher concentrations for constant feeds. My current fert. (which is 18-18-18 with mostly urea) comes with recommendation for 1tsp. per gallon. Now to me, that seems strong. But if you read furthur up, you'll see that someone stated that ferts for orchids are not meant to be diluted, but used as directed. And someone else, who has always seemed sensible, agreed!

But I'm not convinced. When I started this nonsense years and years ago, it was before the boutique fertilizers had become vogue and people were using a lot of 20-20-20 and 10-30-20. The dosage on the container was 1 tsp per gallon. BUT, it was common knowledge that you diluted it to 1/4 tsp./gallon for a constant feed with a plain drench every month, OR 1/2 tsp per gallon 2x a month..

Just trying to pull these two schools of thought together to figure out what's what. Maybe this is why the PPM approach has gained popularity.

Thanks for your input.

J

John,

What I didn't mention, but probably should be included in the equation, is that my fertilizer instructions say to use that amount (1/4 tsp/Gal) for every watering--which I do, except for the flush day. That comes out to quite a lot of fertilizer per Month (though nowhere near 1 Tbsp/Gal).

My baby Phal in all sphag. is fert-watered approximately six times a month (= 1 1/2 tsp/gal per Mo.)

One Phal gets just short of 1 tsp. per Mo. (sphag and fir bark)

The other gets about 1 1/4 tsp. per Mo. (sphag and fir bark)

The Paph. gets about 1 tsp. per Mo (looks like firbark, charcoal, granite, and possibly coconut husk - all small)

I include the media mixes, because one of the Greenhouse Grower articles mentioned that sphag (being quite absorbent) keeps the nutrients available to the roots--another little variable :) among the many.

Sweetcicely

A couple more data points -

My plants in sphag are fertilized every 3rd watering, w/ the 1st watering being plain water, and the 3rd being leaching w/ plain water. There's a color-coded pot tag system to keep track, mainly because I check each of the 90 plants before watering - they don't dry uniformly.

Plants in bark get plain water 1st, fert 2nd & 3rd times, and leaching w/ plain water the fourth. Again, the color-coded system.

Orchid ferts are used full strength - a liquid tbsp or whatever per gallon, mixed a gallon at a time. One time, I used powdered Miracle Grow houseplant fert and cut it to 1/4 strength for a gallon.

Because I tend toward underwatering, plants get plain water right before fert.

Hope this is helpful, Whitecat8

Ok. But again, whitecat, not all orchid fertilizers are created equally. The point I'm trying to make is that "orchid fertilizers" are supplied to you and me in different concentrations, and different instructions. So, saying that orchid fertilizers should be used full-strength is meaningless. Not to mention the many many fertilizers that are very suitable for orchids, and are widely used as fertilizers for orchids, but are not advertised as "orchid fertilizer" per se. Instructions vary, concentrations vary - there are just too many different variables to make a general statement like that. Which is why I asked that the concentration printed on the container accompany a post discussing dosage.

Thanks,

John :>)

John,

You are absolutely correct!! More information = fewer misunderstandings.

--Stitz--

John,

How 'bout this for survey purposes:

1. Is it an *Orchid* (stated) fertilizer?
2. Is it granular or liquid?
3. What is the container listed NPK (i.e., 10-10-10)?
4. Does it mention other trace minerals?
5. What is the concentration recommended for Orchids (teasp. or Tblsp. per Gal. water)?
6. What is the concentration You use (tsp or Tbsp per Gal)?
7. How many times per Month do You actually use it?
8. Do you pre-wet or flush (leach)?

Sc

John & Stitz, you are right. I was speaking in generalities. Usually, I use Green Jungle liquid concentrate but am out of it right now and am using an MSU-type liquid concentration from "that place."

The concentration and ingredients for the GJungle aren't on the Orchids Ltd. Web site.

MSU-type: ... "'Pure Water' version of the MSU formula (3-0.75-4-2Ca-0.5Mg)... Each quart makes approximately 60 gallons of fertilizer at 125 ppm nitrogen."

On the label, there's no dosage for 125 ppm, but it's 2-2/3 tsp. per gallon for 100 ppm N and 4tsp. for 150 ppm.

Nitrogen in this MSU type is nitrate 3.1%; ammoniacal 0.17%. On the list of ingredients, forms of nitrate are calcium, magnesium, and potassium.

Heavens, no - I'm not saying what people "should" do re: fertilizer, just reporting what I'm doing currently.

John, thanks for hanging in there on this and coming back to the specificity that will be helpful in making fertilizer decisions.

WC8

MSU for pure water, dry form, which is 13-5-13 plus micro.
It calls for 1 tsp. per gallon.

During the winter I use 1/4 t. per gallon - starting in March it goes to 1/2 t. per gallong

I use the fert water each time I water but I always leach/flush the pots first. I tend to be an underwaterer so am not comfortable using just the fert water without a heavy flush first. I also use two drops of Superthrive in the fert water.

Brooke

Hey Brooke - Thanks for that. Sounds sensible to me. My conditions tend to be warm and bright all the time since I have an HID fixture in a small room which heats up pretty quick. I usually follow mid-Florida guidelines for my orchids and it seems to work out pretty well. I have "warm" and "warmer" so I'm going to try bumping up feeding a little this year from my conservative approach of 1 tsp/month.

Sc, good ideas. All of that info is good, but at the very least we need the NPK. Just knowing the concentration is enough to have decent communication. The rest can come out in the wash as they say.

I wanted to share a little of what I've run across over the past couple of weeks.

The following link discusses how fertilizers behave in RO water. Discussion includes both generalized and fertilizer specific observations, including statistics re: pH and TDS.

http://www.msu.edu/user/harveyb/Fertilizers.htm

The following link includes more helpful data for the two formulas of MSU fertilizer, including the ppm of macronutrients by tsp./gallon measurements:

http://www.growinhydro.com/21332.html

And finally, Bill Argo's 5-part article, "Understanding pH Management and Plant Nutrition" is available on a website, the mention of which is prohibited in this forum. This one can be pretty heavy, but each time I've read it I've picked up new ideas. It's a process!

HTH

John

Thanks John, It's snowing like crazy and instead of curling up with a good book, I'll curl up with some interesting articles on plant nutrition:

MSU for Pure Water
Total Nitrogen - 13.000%
(Nitrate nitrogen - 12.3%
Ammoniacal nitrogen - 7%
Phosphate - 3.700%
Potash - 15.900%
Calcium - 8.000%
Magnesium - 2.600%
Iron - .177%
Manganese - .088%
Zinc - .044%
Copper - .044%
Boron - .018%
Molybdenum - .018%

Use at 1 tsp/gal

I am feeding most at full strength, every other watering, started this week because most are going strong. I don't flush first, although I am an underwaterer. I haven't had problems with root burn with MSU. I have with other fertilizers.

Thanks again,
Jane

Hi Jane. So according to one of the pages I posted, you're feeding 172 ppm nitrogen when you fertilize.

I'm switching back to MSU Pure too. I think I'll start spring with 1/2 tsp. as a constant feed with a leach every 4th watering. Probably won't prewater catts or phals.

One of my resting catts broke a new growth last week. Finally. George King kept growing all through the winter under my HID lights. But that sheath just turned brown, by the way, and it started a new growth. Sigh.

John

Don't give up John (I say that every year). At least you got a sheath. But I've got two new growths going. I better get something or it's off to a better home. This is a big plant.

All of my Catts are awake and going strong. I think the intensity of sunlight with the warmth did the trick.

I always get so excited at this time of the year. Winter is winding down.

Jane

Checked my orchid Society Database to find when George King flowers here. Late Autumn/Early winter. but that might not mean anything, different climate, no lights etc. Could be that it needs to cool down at night but if you have a large range of Cattleyas you need a range of growing conditions to grow and flower them all. Someone must grow and flower that beast under lights over there. It is one of my many failures and i have a big collection of Cattleyas and different sets of growing conditions.

Thanks Jane and Arthur. I'm not giving up yet. The growth that had the sheath wasn't really bs, and the sheath was also a little small. So in a way it's encouraging that a smaller growth even put out a sheath, right? New growth looks really strong so I'm keepin' the faith baby.

If my Blc. Susan Holguin blooms, it will be a rebloom and I'll be very encouraged. It has two sheaths (from last fall). They both dried which didn't concern me until they formed dark brown halos at the base several weeks ago. So I cut the sheath on one and everything looked ok. Now little proto-buds are starting to emerge so I guess the same thing is happening in the other sheath that I didn't cut.

So, speaking if fertilizer, I wonder if I should start fertilizing it when (if) those spikes start really pushing up?

John