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weakly-weekly? fertilizer for Phals

16 years ago

In the February, 2007 issue of the AOS magazine, Orchids, the featured topic of the CULTURE CORNER was Growing the Best Phalaenopsis. The article was part of a series originally published in Greenhouse Grower magazine. It was modified for orchid enthusiasts with a wide range of growing experiences.

"Plants supplied with 200 ppm nitrogen at every watering were superior to plants fertilized with 100 ppm of nitrogen (or less) at every watering. Therefore, we recommend incorporation of a complete fertilizer delivering 150-200 ppm nitrogen at each watering with adequate leaching."


The widely known MSU Formulation of Orchid Fertilizer, Well Water Formula, is designed for use with Well Water or Municipal Tap Water. In order to achieve a concentration of 200 ppm of Nitrogen, it is necessary to mix 4.0 grams (1 tsp) per gallon of water according to the directions on the label. This concentration is definitely more than weakly-weekly!

I don't use the MSU formula exclusively. I use a variety of fertilizers at higher concentrations than what I interpret as "weakly-weekly".

I have never had a problem with salts. Generally, I try to change the potting media of phals at least annually. I deliberately make exceptions, usually for more frequent changes.

The authors of the article: Yin-Tung Wang, PhD, professor of floriculture at Texas A&M University; Matthew Blachard and Roberto Lopez graduate assistants; and Erik Runkle, PhD, assistant professor and floriculture extension specialist at Michigan State University. This article also discusses phosphorus and potassium.


Comments (49)

  • 16 years ago

    I am terrible about fertalizing and although I have had great growth with out hardly any I am sure I could have better.

    It is weird how everyone seems to start thinking about things at the same time. I went to an orchid show, started thinking about fert. then check here and there is one huge post about fert. and now this one.

    Anyway I too came the the conclusion that I am not going to be as weak weekly. But still weekly. If the tips of the leaves start getting brown I will worry about it and cut back. I leach the pots just about every watering so salts should not be a problem.

    If they are I recommend Epson salts they tend to help take out the harmful salts.

  • 16 years ago

    I think one teaspoon to a gallon of water IS weak. I use that quantity throught the main growing season. During the short, dull days of winter I cut that back to one quarter to one half of a teaspoon.

    Since most fertilizers recommend one tablespoon to a gallon once a month, then the teaspoon to a gallon more often I would think would be considered a weak dose.

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    I grow in a spare bedroom also and have about 45 phals, @15 summer bloomers and the rest winter/spring or random bloomers. I open a window (day and night) in the fall (like now) and also turn my lights back from 15 to 13 hrs for a couple of months. I'll be changing the light cycle very soon. (I figure between light change, lower temp change and such, I should be covering most bases needed to bloom these plants???) I'll continue to crack a window until the night temps in the room start dropping below 60 degrees. In the fall my grow room probably averages 75+ highs and 65- lows. Also, this room seems to have about a 10-15 degree drop from day/night year round, as the lights generate a lot of heat during the day and the A/C lowers the temps at night. Lights go back to 15 hrs in late Nov. or early Dec. In fall/winter, I try to keep the summer bloomers in the warmest areas of the room, the rest are placed where they can fit. Fertilize weakly/weekly year round and switch up ferts occassionally. Flush with pure water @ every 4-6 weeks. I grow lots of other types of orchids too, (@175 total) all in the same room, so this treatment is not 'just for the phals'. Last year I had about a 90% bloom rate for my phals. As a side note: My first winter/spring phal is spiking. By first, it is the first of the season to spike and the first orchid I ever purchased (Jan '02). It's a hybrid lipstick phal ('Happy Girl') that is pretty standard, but special to me. HTH, Bob
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  • 16 years ago

    Hi, Stitz. It was very interesting to read your comments about using more fert than the weekly/weakly on your phals.

    I am definitely giving more than weekly/weakly. I want them to be gung ho to grow and bloom. I like to "see" the growth every week or so, so I give as much light, warmth, and everything else I can. I also get more growth than the 1 leaf every 3/4 months people talk about.

    I use dyna-gro grow at 1/4 concentration *every time I water*. The smaller pots in winter need watering every other day. So that works out to nearly 1/tsp/gallon weekly for them. However, I honor the taboo by never giving them the whole 1 tsp/gal in a single dose. It's spaced out. I've been tempted a few times to try a higher dose at one time, but afraid to burn the roots.

    Larger pots need water less frequently, maybe twice a week, and get whatever it works out to. I pour straight water thru probably once a month, but often less frequently.

    They actually get some amount of fert greater than that, because I also add timed release fert to all the pots. This follows advice from Fender's Flora, and I like the results.

    I don't get salt crusts on the clay from just the Dyna Grow. I do get it sometimes with the time-release, probably used a heavy hand with it. But flushing with pure water for the next N waterings til the salts disappear seems to take care of it.

    I'm definitely not recommending living on the edge to anyone. But I'm happy with the results of what I do. So far I haven't had any particular problems from this-- no "soft growth", and roots are good in the sphag.

    Growth is faster than the 1 new leaf every 3 months thing people talk about. In summer I get a new leaf every month to 6 weeks on the bigger plants. Probably less than that in winter, but still more than 1 new leaf in 3-4 months.

    I do believe the fertilizer and the other growth factors have to be in balance. Very likely the weekly/weakly makes sure phals in the usual indoor home environment won't be over-fertilized or over-watered. It's easily remembered and applied by novices.

    For phals that are in more favorable conditions, I can see how more fert would be appropriate and certainly would support faster growth if warmth and light can be increased as well.

  • 16 years ago

    Hi Stitz!

    Thank you for bringing the gist of the AOS article to the forum for comment. It is certainly something to think about. I have no idea how many ppms of nitrogen are available to my Phals. Did the writers define what they believed constituted the "Best Phalaenopsis" or "superior" plants?

    My Phals may not be beauty queens, but they are healthy, with good roots, regular growth, and large blooms. Though I am happy to improve their culture, I want to be reasonably sure that changes will improve their health in both the short and long run.

    I get nervous when experts start advising the use of a great deal more of any element than would be natural to their native culture. I know, of course, that growing these mostly tropical treasures in the house is not "natural" and that growers do have to compensate, but I suspect that there are such things as Too Much light (short of sunburn) and Too Much of any element of fertilizer (leaching notwithstanding).

    My guess is that lighting or fertilizing the heck outta these plants has to have a deleterious long term effect.
    It would not please me to collect a Best of Show one year, only to lose the plant in the next.


  • 16 years ago

    Of course you should not push them too much, but...

    The amount of fert. a plant can take is a direct correlation to the amount of light it receives/can receive.

    So if it is going down hill and seems to be from toxicity try increasing light (within reason) or decrease fert.

  • 16 years ago

    Those articles on growing phals are still online. See first of 4-part series on link below.

    I have my phals under enough light that many leaves have a red blush, but haven't tried increasing fert (I use mostly MSU municipal water, about 1/3 tsp per gallon). I think I will bump it up to 1 tsp on the healthiest plants.

    One of the lecturers at WOC said after you visit orchids in central America in their natural habitats, you grow them differently. More water, for example. He said it rains in some habitats almost every day.

    Here is a link that might be useful: series on phal growing

  • 16 years ago

    Sweetcicely asks, "Did the writers define what they believed constituted the "Best Phalaenopsis" or "superior" plants?"

    I can't directly answer your question. At the time of publication (Feb, 2007), I wasn't a subscriber. From that issue:

    "In this second article of our four-part series, we present research-based information on how medium, watering and fertility influence growth of potted phalaenopsis."

    mehitabel--Thank you for your reference to using time-release fertilizers with phals. I wasn't aware that Fenders' recommendation extended to Phals also.

    I started using time-release on some orchids last year. My results seemed inconclusive. Clearly, some plants showed benefit. Some plants seemed "indifferent". I haven't gone to Phals, yet....! It's definitely worth serious thought. Do I hear volunteers in the distance?

    In addition to the MSU formulas, I also use Grow More and Peters' formulas. During the "main growing season", the orchids also benefit from the occasional use of Miracle-Gro Tomato Plant Food. The tomato fertilizer doesn't contain trace minerals like the others, so I limit its use. I don't hold back with the Miracle-Gro: 1 Tablespoon per gallon of water!


  • 16 years ago

    this is a very interesting thread. thanks for sharing your experience. i had not realized that they would like tomato plant food or that they like acidic type fert. now I have more experimenting to do. what i have found so far is that chemical ferts have given the leaves dark brown tips and soem of the roots have turned black in color ( they are still firm - just color has changed so i am not thinking that it is rot). I fertilize every 3rd or so watering and I use 1/4 teaspoon to gal. so it is very mild. so I am going to try and stay with organic ferts. this year and see if it makes any difference.

  • 16 years ago

    I don't believe in heavy fertilizing. I have used the time release type on large plants in summer only, to prevent pouring all this nitrate into the ground. I have seen no difference between time release and standard mixes. I have used time-release for years (Oscomote).

    I fertilize at full strength whenever I fertilize. I have a large mix of plants and each get treated differently. I only have 8 Phals and only feed them when I see signs of green growth and roots. I do not feed them in bloom nor any of my other plants. I do not fertilize any plants which are resting.

    I do not believe a Phal making new leaves every month is healthy and will eventually lead to the decline of the plant. That goes for any plant which follows a natural cycle. In my opinion a Phal which makes leaves year round is being forced to grow by keeping it too warm and light too high. That can be done to prepare a plant for show, but to do that year after year will shorten the life of a plant.

    Any gardener knows that promoting too much green growth with overuse of nitrogen will weaken the plant inviting disease.
    My Phals are all making new leaves and haven't had a drop of fertilizer since November. They are full of flowers and will stay that way until I am bored with them which is usually around May. Then the spikes come off and they spend the Spring and Summer making leaves and roots.

    Most everything else is starting growth and I have started fertilizing them but not every watering. The house is dry and the light is not strong. I like slow and easy until they can go out and get the sun, air and humidity.

    Plants grown year round with RO or rain water probably should be fertilized throughout the year to help replace missing nutrients. But I usually don't as I'm lazy and occasionally give them a bottle of Poland Spring.

    I use Miracle Grow for Roses with micro nutrients in Summer outside (cause I'm lazy). I alternate with MSU for tap. My hose (tap) water is acidic and I find the plants do fine with those. But they don't get fed every watering. I am bad about that and force myself at least once a week. As I said, any plants in pots 8in and larger get Oscomote without additional fertilizer.

    Dens are the only plants which get a liquid fertilizer which uses urea and is low in N. I'd have to look at the bottle but its about 10-35-8 (might be way off on the Potash). That's why I was interested in the Orchids article John mentioned and which plants they tested.

    My indoor conditions in this zone dictates my use of fertilizer. I enjoy learning what others do in their growing environment and have found successful.


  • 16 years ago

    The articles are geared for optimum conditions. In other words the right light, temperature, humidity and watering. The kind of thing that happens in a commercial greenhouse with thousands of the same plants at the same stage of development. They are interested in getting the plant mature enough to bloom in the least time.

    In the wild the plants get by on decaying leaves and the occasional bird pooping nearby. They appreciate any fert that they get and any extra runs off.

  • 16 years ago

    A lot has been added, here, since I left to read the first article.

    Jane ~ What is Polish Spring?

    Thank you, Hollyt, for the link to Part 1 in Greenhouse Grower. It was so interesting that I went on a googl-odyssey to find the others. Only Part 3 eluded me, until I found a link to one of the authors (Lopez), then to another (Runkle) and through a couple more links, where I finally found Part 3 (linked, below).

    Stitz ~ None of the parts define what is meant by "best Phalaenopsis," which leaves me to assume it means overall health, strength, high bud count, and large flower size (for large flowering Phals). All of these points are mentioned.

    The original articles were intended for greenhouse growers in general, but commercial growers in particular. And as Richard said: "They are interested in getting the plant mature enough to bloom in the least time." The original for part 3 is a bit longer than the AOS article. (That may be true of the others, as well, but I only compared Part 3.)

    Thank you, Stitz, for starting this. All four articles are fascinating and contain information I have not seen elsewhere. Holly's link goes to Part 1; the link below goes to 3; and 2 & 4 can be found with the keywords: Greenhouse Orchid Grower part 2.


    Here is a link that might be useful: Phalaenopsis article

  • 16 years ago

    I'm kind of with Mehitabel on this one. My phals (grown indoors under lights year round) produce leaves year round, but it seems like only 3-4 a year. I have several spiking now and also producing new leaves. I switch the ferts I use regularly (Dyna-Grow Grow/Dyna-Grow Bloom and third type). Once a month I water with no ferts to flush, but the other times I use the weakly/weekly (1.5 teaspoons to 2.5 gal of water). I generally water my phals once or twice (small pots) a week, generally with the same watering mix that I created on Saturdays. So if I mixed up a fert batch on Sat, most plants watered more than once a week get the fert. My daily misters get non-fert water daily, but are watered with the Sat. water mix once a week. I use this for everything, some sensitive plants get flushed more often, but I don't have the time or energy to really manipulate their watering differently. Hey, they either sink or swim, only very special plants get any special treatment.

    I used to use more fert (maybe 1 TBS/gallon or more) but was seeing leaf tip burn so I cut back.

    The only time release I use is what may have been in the pot when purchased. I grow a lot of my phals in S/H, I was never really sure how S/H and timed release ferts would interact so I have just not tried it to see.


  • 16 years ago

    All of this fertilizer discussion is very interesting. I've gone between being a very dedicated fertilizer person - to not so dedicated and back again, and again's always been a question for me.
    I am fortunate in that I live on the edge of a sub-tropical river swamp. It's in my backyard in fact. There are orchids growing in the trees. Mostly Epidendrums and few others. When the large trees fall, it makes a haunting sound that travels up through the swamp and all within earshot have no doubt as to what has happened. I set out to find that fallen tree and "save" the orchids. LOL....I've also saved my share of baby squirrels and baby birds ....helpless victims of their fallen home. Other victims too - the orchids. If you don't make your way quickly, wild hogs will find, eat and maul what's left of the orchids after their sudden and abrupt trip to the ground.

    The wild orchids are never alone. Their roots are intertwined with various air plants, various ferns, mosses and lichens. To "save" the orchids you have to get right down in there - so to speak. The first thing you see is a lot of leaf matter, dead and decaying. And, a lot of insects - beetles, ants, small bugs that take flight when disturbed. Apparently none of these cause any (obvious) harm to the orchids or other plants, and I suspect do a lot more good than harm. They all live in and around this root mass of mixed plants. It's "dirty" - has a pungent musky smell. Tiny baby orchids are down in the depths well shaded by the overgrowth. It's a mass of plants that have rambled all over each other (no "shoes", lol), and this mass is almost always damp...... it would hold moisture even after days of no rain. Decaying leaves and plant parts, bug poop, dead bugs, add the rain = fertilizer .....THE perfect fertilizer.

    Your source is correct hollyt changes the way you look at orchids to see them in nature, changes the way you think of them, and grow them.

    I grow a lot of orchids mounted or in open baskets with their wild counterparts in mind. When I am thinking of buying this or that orchid I always Google images of that orchid growing in situ. Looking at a wild orchid in Belize is interesting, but I am just as interested in what is around that orchid, and what isn't - it's immediate environment. I try to grow that orchid as close to it's wild relatives as is possible, for me. this got so long......
    I had high hopes when I discovered the "worm poop" fert at HD. The jury here in my GH is still out on that one.
    I had good luck with fish emulsion .....but, oh my goodness - THE SMELL.....
    I've had some success of late with time-released ferts.......
    I don't know why - but the blue stuff or the green stuff the back of my mind....just doesn't seem - right?
    I think I come down on the organic side..........

  • 16 years ago

    Since Stitz posted the info for phals I will stick to phals and not post about dormant plants or salt sensitive plants that cannot be fertilized at "normal" rates. I have those too :>)

    I have always used the weakly weekly concept with urea free fertilizer during the winter, multiple brands. This was when I grew under lights and now in the g/h. When the temps rise, I increase the fertilizer to 1/2 t. My pots are flushed each time I water, then the fertilizer water is used on them.

    When we switched to rainwater I switched to MSU for pure and might not be totally happy with it for the phals. On some of the light green leaved phals I started noticing signs of a nutrient deficiency so I used a mild dose of magnesium. I noticed no such change in the dark green, grey green, maroon tinged or patterned leaves. I started mixing my fertilizer water with 50% of my city water. I don't know if I guessed right or wrong - it was a gut decision. Time will tell.

    I don't see a rest season for phals nor do I worry about growing too many leaves on the plants. I see them slow down some, particularly in the g/h this very grey winter, but they don't stop. Right now, every summer blooming phal is growing new leaves and it is not from optimal heat or light.

    Inside under lights during the winter, I always had growth continuing at a steady pace. If the temps and lights are suitable, they just happily continued to grow. The more leaves and roots, the more spikes. I have never worried that a phal is growing too many leaves, I take it as a happy phal.

    Many of my phals get watered multiple times a week and some only once a week. It depends on the size of the plant, the container and the media. They all get the flush and then the fertilizer water.

    I know sweetcicely and jane don't fertilize when a plant is in bloom but I do and have never noticed any change in the bloom cycle. Blooming takes a lot of energy out of a plant and I want to make sure the reserves of the plant aren't reduced to support the blooms.

    I also use two drops of Superthrive in each gallon of fertilizer water. Does it help? I don't know but I have a pint of it and continue to use it. I know it doesn't hurt the plants/bloom.


  • 16 years ago

    Sorry stitz - I posted the above to the wrong thread. Got lost I

  • 16 years ago

    Just wanted to mention that another article makes an incidental reference to phals (and dens) appreciating higher levels of fertilizer than generally applied, Orchid Growing 201 in February 2008 Orchids. The article states that the author/growers apply a solution three times stronger to phals and dens than that given to their other orchids.

    This seems also to coincide proportionately with orchid126's post that full-strength for most fertilizers is 1 tbsp per gallon compared to the 1 tsp/gallon that would correspond to other less demanding orchids (surprisingly to me, catts, for instance).

    Me, I must be mistaken in my own understanding that 1 tsp of a standard 20-20-20 or equivalent is the accepted weakly-weekly dose *per month*, preferably broken up into two or more feedings with a leach after every three feedings.

    John :>)

  • 16 years ago

    PatÂI purchase worm castings by mail-order in the 25 lb bag. I normally use it around my tomato seedlings at transplanting time. What are your experiences with orchids, so far?

    BrookeÂYou are carefully watching your plants. Smart move. I mixed the MSU Pure Water formula with city tap water somewhere along the line. I quickly noticed some browning of pseudobulbs in Cattleya type plants.

    I didnÂt bother collecting rain water this autumn/winter so that I wouldnÂt have a repeat. Maybe, IÂll restart rain water for the few phals which havenÂt had a good winter.

    I use fertilizer solution at every watering on the phals except, about once/month I flush thoroughly with tap water. When I repot the plants, I havenÂt noticed any accumulation of chemicals on the roots or the inside of the pot. I change the media often enough that it isnÂt a problem.

    I recently learned that a local commercial grower uses fertilizer in concentrations strong enough to dye his NZ sphagnum blue! This grower changes the media in those plants at least annually.


  • 16 years ago

    Stitz I originally tried the flush every fourth time with no fertilizer but I found it confused my old brain trying to remember what got flushed and what still needed it.

    I already have markers in the pots for the day they were watered and tried adding another marker for a flush or a magnesium or a bloom booster so I wouldn't repeat an application. Since my phals are in everything from a 2" pot to a 6" pot, plus mounts, too confusing for me.

    The suspicious coloration that might be a nutrient deficiency did appear about three/four months after my drop from 1/2 t. to 1/4 t. per gallon. As I said, I am just guessing at this point, trying to consider all the changes made in the last six months.

    We wanted to get the rain water system installed in mid-summer but it didn't rain :>) We were in a severe drought last summer and didn't start getting reliable rain until late fall. We have also installed a RO system for our next drought, which hasn't been this winter :>)

    On March 1 I intend to up the fertilizer to the 1/2 t. but am considering increasing it to 3/4 t. for my three hottest months. Too many decisions - too few brain cells.

    Brooke - who hasn't seen even a piece of the sun for seven L-O-N-G days and none promised for the next two - yuck!

  • 16 years ago

    I was reading about "worm poop tea" on the net one night Stitz, went to HD next day and there it was. It was a 16oz. spray bottle, and you use it straight from the bottle, no mixing. I bought two but it didn't get me far. I tried it out on miltassia, brassia, oncidium and phalaenopsis. These seemed to respond well. HD had one for orchids, tomatoes and a couple of other things (can't remember). I liked it, and went back and bought more, but 16 oz bottles don't last long when you have 200 some odd orchids to fert. I need to look for the worm castings and see if you can use that with rain/RO water.

  • 16 years ago

    Polish Spring is spring water. I buy it by the case to drink and give my plants a bottle now and then. I can't use my well water because its softened.

    I also noticed, what seemed to be slight nutritional deficiencies in some of my soft-leafed plants, thus the Poland Spring Water.


  • 16 years ago

    Thanks for bringing this up, Stitz.

    Pat, it's wonderful that you can see orchids in the wild.

    For some reason, when I started out, leaching didn't seem to apply to my plants. Geesh. Then a favorite Phal in sphag started struggling and was diagnosed w/ fertilizer burn. Too bad I had to learn the hard way.

    Since then, plants in sphag get fertilizer every 3rd time, the other 2 being plain water and leaching w/ plain water. Before fertilizing, I water with plain water - partially because I underwater. Plants in bark get fertilized every 2nd and 3rd time, w/ plain water the 1st time and leaching the 4th time.

    Usually I use Green Jungle at the recommended strength - maybe 1 tbsp/gallon. (Don't have any right now.) It's available locally, so there's no shipping $$.

    Brooke, I DO have a color-coded watering system because I check each of the 90 plants before watering, and they don't dry out uniformly. 5" colored pot labels work great.

    Apologies for the size and fuzziness.


    Light blue = plain water
    Green = fertilizer
    Brown = leaching

    So, the brown tag is facing inward, which means leaching was the last thing that happened. Next time the plant's dry, the brown tag will go to the end of the line, against the white label, and the blue one will be "in front," so the plant will get plain water, if that makes sense.

    D'ya think anyone really fertilizes weakly, weekly?


  • 16 years ago

    My understanding was that, for orchids anyway, it's better to error on the side of less fertilizer than over-feeding. Weakly-weekly isn't something I'm comfortable with. I stick to once a month, and little even at that.

  • 16 years ago

    OK WC8 - you've confused me. What is the difference between watering and leaching?


  • 16 years ago

    Watering probably means simply pouring water through the plant,
    Leaching is probably soaking the entire pot in some water so the salt has more time to dissolve.

  • 16 years ago

    bunny, that's probably a good rule of thumb for starters. Comparatively speaking, orchids are light feeders. But there are techniques that probably suit them more than others, and variables in environment that, over time, can and should be taken into consideration if we want our plants to perform to their potential.

    The weakly weekly rule reflects the idea that in nature, orchids duing growth will be receiving a frequent supply of nutrients. So although once a month may be somewhat effective, it's also a reasonable assumption that since orchids are very highly evolved plants, they may not have the capacity to store nutrients for long periods of time. So adopting a regimen that supplies them with a generally continual supply of nutrients (at least during growth) would be the logical tact. 1 tsp. of a 20-20-20 or equivalent per gallon per month is fairly weak. For weekly weakly, you divide that tsp. up into roughly 4 parts, feeding 1/4 tsp per gallon per week, watering with a leach every fourth watering or once a month.

    This is not meant as advice to anyone. It's just to illustrate the logic behind the basic weekly-weakly type of regimen.


  • 16 years ago

    Meant to say that the 1/4 tsp./gallon is used as a continual feed, with a leach at least every month. I used to do that but then I got tired of mixing all that fertilizer solution. On the other hand, I think my plants did better.


  • 16 years ago

    John, The last paragraph in your 11:02 post reminds me of a mutual fund's risk warnings :-)

    Flowering data represents past performance and is no guarantee of future results. Future flowering and the overall condition of the plant itself will fluctuate. Flowering for you may be better or worse than that quoted.


  • 16 years ago

    Very good, Stitz. :>)

  • 16 years ago

    Brooke - "Watering" means watering till it runs out the bottom of the pot. "Leaching" means hauling the plant down to the kitchen sink and spraying water through the medium so it equals filling up the pot 4-5 times.

    Side note - at the same time, I hand rinse all the leaves under the running water, so the medium gets that additional leaching. Someone here said that, if you clean the leaves of a new plant w/ lemon juice, milk, whatever, all you'll have to do after that is rinse the dust off. Well, unless you get something on them. It's been true for my plants.


  • 16 years ago

    I think I over water or I leach them each time or I call it flushing the pot.

    Plants do love to have their bath don't they!


  • 16 years ago

    pcan-z9 wrote:

    "I am fortunate in that I live on the edge of a sub-tropical river swamp. It's in my backyard in fact. ...."

    Before this thread gets away, I want to thank Pat for that river swamp reverie. It awakened every sense and played like a love song to her enchanting place.


  • 16 years ago

    Thank you, Jane, for revealing the nature of your secret ingredient :)


  • 15 years ago

    Can anyone tell me when one should switch from high N fertilizer to high P one?

    After flowering is (imho) definitely high N fertilizer, until I see the spike? Or?

    Can the same principle be used for other types of orchids?



  • 15 years ago

    I re-read this thread and was reminded about how great it was. Kate's question may be the ONLY aspect that wasn't covered.

    I am a weakly-weekly low even numbers year round kind of guy (a few specific exceptions like dry Dens in winter). But if I did use a bloom booster, it would be in the couple of months before the spike started for Phals.

    With other orchids, this would probably not be good. Some orchids bloom early in the growth cycle, some during, and some at the end.

  • 15 years ago


    Thank you for confusing me even more º
    Honestly, thanks for your reply, now how do I know when my 1st year baby is about to surprise me? Any hints or maybe for phals after the two new leaves are grown? Although my 1st and only phal (yeah yeah, newbie-booo) grown its leaves one month, or maybe even less, before the spike. Oh dear¡K. º

    Will it hurt (phal) to use a bloom booster after the spike appeared?

    Another newbie question ¡V do I still need to fertilize when the spike is formed (grown about 10-15 inches) and flower buds have just appeared? I know one doesn¡¦t feed phals when they are in bloom, but when is the best (safest) to stop?

    Thank you!


  • 15 years ago

    I would say switch to the lower nitrogen fertilizer about the time that the plant has been exposed to the cooler temps at the end of the summer. Usually they bloom sixteen weeks later.

  • 15 years ago

    I never use the bloom booster and don't really plan on doing it since I use the MSU for pure water. I fertilize in the winter with 1/4 strength and in the warm months, 1/2 strength each and every time I water. If I water a pot more than once a week, it still gets fertilized.

    This does not apply to anything needing a dormancy period.


  • 15 years ago

    Hi Kate!

    Like Richard, I found this to be an excellent thread. My granular fertilizer is an already weak, just-for-orchids, year around formula (higher N number), and though the numbers are not even, it seems to work just fine.

    I have two mature phals--coincidentally, one is a hybrid used in the experiment about which the "Growing the Best Phalaenopsis" article was written (Phal Miva Smartissimo x Canberra). These phals have been in my care for four and seven years. Each phal spikes every fall (around Oct. 10-25) when the temperatures drop, here, and blooms the following late-winter/early spring. Each of these has just spiked for this fall.

    The only time I have ever used anything to prompt blooming was when I was desperate :) after trying for three years to rebloom the oldest of my phals. I gave it a dose of epsom salts--which, I believe, came very close to killing the poor plant. Three weeks later it turned a sickly green, so I stopped the Epsom Salts and flushed it with plain water. In desperation (now the phal's) it Spiked! ...and bloomed, almost three months later.

    Except during blooming I use the same weak fertilizer solution with each watering, year around. My phals do spike and grow leaves at the same time. I don't know whether that would be the case with a bloom boosting fertilizer, having never used one.

    Though not everyone, here, does the same, I stop fertilizing as soon as the first bud blooms on a spike. To continue fertilizing during bloomtime always results in loss of blooms for me.

    Sorry to go on and on! I hope something here helps.


  • 15 years ago


    Once a month I flush each pot with plain water to wash out accumulated salts....but you probably knew that already :)


  • 15 years ago

    What if phal flowers twice a year?

    If I water a pot more than once a week, it still gets fertilized
    I water it once a week, it isnÂt big and thirsty and it managed to spike with no food for few month now (didnÂt know it needed it)
    IÂm confused whether I should use nigh N or high P at the moment.

    Hi Sweetcicely! =)

    I have dag out all info there is on the Web during pas few weeks and most of it is similar to your advise.

    Couple things that were different are that tests at Michigan Uni showed that itÂs not higher P number that is responsible for better bloom, but the drop in N number that stimulates phals to flower.

    Also, somewhere else I have read that it is advised to use higher N food for 6 months after the bloom and then switch to higher P before the actual bloom, just as you said  when the 1 st bud is on the spike. Problem is they bloom as and when they like, so it might not be 6 months at all, thus my question.

    I personally think that if phal is happy with conditions it is kept in even number fertilizer should be just fine. As a multi-vitamins for a healthy person. Surely with a "flash" break =)

    i attach photo of my phal in April during last bloom.

    Thank you


    Here is a link that might be useful: {{gwi:144258}}

  • 15 years ago

    Stitz, to your original post, I'd add a comment...anyone who has seen one of Dr Wang's phals (and I've just now had the good fortune to buy a couple seedlings) will immediately be a believer in his culture. Unfortunately Texas A & M can no longer boast this talented grower as a member of their school. The evening Dr. Wang spoke to our OS meeting, I was out of town. I also missed hearing him speak at the WOC. I have seen one of the plants grown by Dr. Wang in bloom and it was incredible. Many leaves spanning well over couple feet, multiple branching spikes with individual blooms as large as your hand. I was told he brought some equally well grown nobile type dends to our meeting.

    However, it is as Richard said above. It is not just the fertilizer, it's a totally controlled growing enviornment. You can find some more information on his method listed on the FAQ page under the title of 'professional grower of phals' (or something like that).
    Dr. Wang's talents are now being directed to commercial production at a large California nursery.

    Happy growing. Sheila :)

  • 15 years ago

    Kate, that plant is certainly well grown. It sounds like you have a hybrid that likes to bloom and doesn't seem to be influenced by cool temps or short days. You might consider switching to an MSU type fertilizer all year round or alternating the regular nitrogen and low nitrogen fertilizers. But from the looks of your plant I don't see what your dilemma is. You're obviously doing something right. Nice growing!

  • 15 years ago

    Kate, I ditto orchid126. On the one hand, you can learn by careful experimentation. On the other, you need not mess with success--Your Phal is an elegant Beauty! Enjoy it.

    And thank you for the nice picture :)


  • 15 years ago


    I think there was a little confusion about my post.

    You wrote: "...and then switch to higher P before the actual bloom, just as you said  when the 1 st bud is on the spike."

    Someone else may have said that. I was saying that I withdraw ALL fertilizer when the first flower bud OPENS--not when it appears on the spike.

    Also, you wrote: "...tests at Michigan Uni showed that itÂs not higher P number that is responsible for better bloom, but the drop in N number that stimulates phals to flower."

    That may be the case for "better bloom" in Michigan U. trials, but I was speaking only about stimulation for spiking. I make no change in fertilizer/food. My phals seem to spike in response to the 30+ degree dip in temp. that we experience at this time of year.

    Hope the clarifications help.


  • 15 years ago


    Thanks. This photo was taken in April when it bloomed for me for the first time. I have bought it with two young spikes along with "complimentary" bottle of fertilizer  about 5ml big of some blue stuff. The instruction said feed it until the first bud is formed then stop.

    So it did bloom and then I stopped feeding it until I saw a new young spike appeared in September. As a newbie I started checking on what to do with it now and realized that I missed about 4 months of feeding! :((

    My dilemma now is that I have started feeding it "weekly and weakly" with high N fert. Then I have read that thereÂs a "bloom boost" one available and I got confused on what to actually feed it. get more growth with N or more flowers with P


    I think there was more confusion with my reply than with your answer =))

    The "bloom booster" supposed to be used after 6 months of feegin with high N fertilizer, until the first bud is formed. Then stop feeding phal until it finished flowering and start all over again after that.
    That might work ok providing that phal is flowering once a year when mine obviously spikes with no food at all for the 2nd time already!

    Thanks for the compliment  I love elegant white flowers. At the moment IÂm looking for a couple yellow and orange color phals to grow on the N window in the kitchen under artificial light. I was hoping to pot them later in one long pot. But thatÂs a different story =)


  • 15 years ago

    Bloom booster and orchid food are terms invented to boost sales and confuse newbies.

    Kate, read all the posts in this thread and sift out what you need to know.

    The high and low Nitrogen stuff is fine if you only have a few orchids or are only growing say one Genera.

    But what happens if you have a thousand orchids of mixed genera that bloom different months of the year so that i feed low nitrogen when it is not so warm and higher Nitrogen in the summer months. No difference that i can discern. Conditions are much more important than fertilizer.


  • 15 years ago

    Kate, I repeat, it sounds like you have a hybrid that likes to bloom and doesn't seem to be influenced by cool temps or short days. You must be doing something right to make the plant so happy. You shouldn't change anything in it's culture.

    With regard to fertilizer, the theory is that nitrogen promotes leafy growth and low nitrogen produces blooms. Less nitrogen might scare the plant into thinking it's going to die and it starts sending out blooms that might become polinated and the plant can procreate.

    Many phals need a cool down in the fall and will bloom approximately 16 weeks later. This type of phal might benefit from a switch to low nitrogen fertilizer at this time. But because your plant blooms a couple of times a year it sounds like the type of plant that isn't influenced by these factors.

  • 15 years ago


    point taken  IÂll stick to the usual WW routine =)

    orchid 126

    if not feeding plant for months is "something right" then I canÂt agree more =)))

    I think it's very happy with the position  getting lots of indirect light and maybe (if lucky!) an hour or two of very low sunset and even this light is filtered through the trees outside the house. The temperature drops just a degree or two in the evening  normal for window sill area.

    Anyway, so far I used higher N food and itÂs still happy =)

    PS. Happy Voting America! =)

  • 15 years ago

    Thanks, Kate! Personally, I'm glad to be done with it (voting, etc.)

    You keep on keeping on the way you have, and I'm sure you'll see that beauty in bloom by the end of winter. Please share your winter "lift" with us. :)