S/H Watering/Fertilizing

[Zoren]

Good morning members. I am looking into S/H growing of orchids. I've read 'First Rays LLC' and have started re-potting some of my orchids. I have rinsed and soaked the LECA in a mixture of water/kelp/superthrive and fertilizer. The question I have, has to do with watering/fertilizing mixture. I made a (I'll call it a 'Feeding Mixture' lets label it FM) of water/kelp and fertilizer and use this in my watering schedule. As I have said before: Live in Florida--Grow in Sun room--Temperatures High during the day and night--AC on at night to 75 F--Good humidity --Facing SW--SSW afternoon sun and heat. It seem to me that I have to water one to two time per week. Should I use my FM at every watering or should I feed once/week and just use water if some of the orchids need a second watering. I use tap water: The TDS 144 ppm--EC 288 us/cm--PH 7.2, is this to high should I lower the PH? Any help on the subject of S/H orchid growing would be very helpful.Of what I've re-potted already I've noticed vast improvements, thank you...Zoren...

[Ray]

For watering twice a week, I would recommend about 35 ppm N - divide 3 by the %N of your fertilizer to get the amount to use in teaspoons/gallon - and apply it at every watering, flooding the pot each time. If you end up only watering once a week, I would use twice that amount of fertilizer. Measure your TDS after mixing a known amount of fertilizer, that will vary with fertilizer choice.

I would not add any stimulant (kelp, Superthrive, or KLN, and never use them together) to that more than once per month. Once the plant's systems have been excited by the auxins, it undergoes a series of deminishing "waves" of alternating cytokinin and auxin production, and that gets back to a normal level in about three weeks. Over-exciting the plant by too frequent stimulation can lead to deformed flowers and/or stunted growth.

[marcmaubert]

Originally Posted by Ray

For watering twice a week, I would recommend about 35 ppm N - divide 3 by the %N of your fertilizer to get the amount to use in teaspoons/gallon - and apply it at every watering, flooding the pot each time. If you end up only watering once a week, I would use twice that amount of fertilizer. Measure your TDS after mixing a known amount of fertilizer, that will vary with fertilizer choice.

I would not add any stimulant (kelp, Superthrive, or KLN, and never use them together) to that more than once per month. Once the plant's systems have been excited by the auxins, it undergoes a series of deminishing "waves" of alternating cytokinin and auxin production, and that gets back to a normal level in about three weeks. Over-exciting the plant by too frequent stimulation can lead to deformed flowers and/or stunted growth.

Is 25 ppm of N per week too little? On Sundays I completely flood every orchid, and I wait until Wednesday or Thursday to just refill the reservoir. On Mondays and Fridays, if it's been hot and dry, I spray the top of the media until the top layer of the LECA looks wet. All of this spraying and refilling is done with the same fertilized water I prepared on Sunday. Now I'm not sure if I'm under-watering and under-fertilizing my orchids, but I don't want to waste excessive amounts of water. Do you flood every orchid everyday? what do you do with all of the excess water?

[Ray]

Originally Posted by marcmaubert

Is 25 ppm of N per week too little? On Sundays I completely flood every orchid, and I wait until Wednesday or Thursday to just refill the reservoir. On Mondays and Fridays, if it's been hot and dry, I spray the top of the media until the top layer of the LECA looks wet. All of this spraying and refilling is done with the same fertilized water I prepared on Sunday. Now I'm not sure if I'm under-watering and under-fertilizing my orchids, but I don't want to waste excessive amounts of water. Do you flood every orchid everyday? what do you do with all of the excess water?

An orchid in nature gets fed every time it rains, and analyses of that has shown it to be typically under 10-15 ppm (rarely up to 25) Total Dissolved Solids, not just nitrogen. Fresh, flowing (aerating) water is far more important.

For a plant to add about 500 grams of mass - maybe a month for corn, a couple of years for a cattleya, or a lifetime for a little pleurothallis - it must absorb and process about 100 liters of water, but only about 5 grams of fertilizer nutrients.

You should flood the pot (which I define as "fill the rapidly pot to the top, and let it drain") at every watering, and never just "top up" the reservoir. As the LECA dries, the minerals precipitate in the pores, and don't quickly redissolve when rewetted. Repeated soaking/drying cycles concentrates the mineral residues, and if you have only topped-up the reservoir, rather than flushing the medium, it accelerates the process.

I did water some plants daily for six months as an experiment, but usually only get them 2-3 times a week. I just let the water drain.

The name of the technique implies a lot of water; if water usage is a concern that takes a higher priority than the care of your orchids, you might want to consider a different technique.

[marcmaubert]

Originally Posted by Ray

An orchid in nature gets fed every time it rains, and analyses of that has shown it to be typically under 10-15 ppm (rarely up to 25) Total Dissolved Solids, not just nitrogen. Fresh, flowing (aerating) water is far more important.

For a plant to add about 500 grams of mass - maybe a month for corn, a couple of years for a cattleya, or a lifetime for a little pleurothallis - it must absorb and process about 100 liters of water, but only about 5 grams of fertilizer nutrients.

You should flood the pot (which I define as "fill the rapidly pot to the top, and let it drain") at every watering, and never just "top up" the reservoir. As the LECA dries, the minerals precipitate in the pores, and don't quickly redissolve when rewetted. Repeated soaking/drying cycles concentrates the mineral residues, and if you have only topped-up the reservoir, rather than flushing the medium, it accelerates the process.

I did water some plants daily for six months as an experiment, but usually only get them 2-3 times a week. I just let the water drain.

The name of the technique implies a lot of water; if water usage is a concern that takes a higher priority than the care of your orchids, you might want to consider a different technique.

Ok, I'll try to flood twice a week during the growing season instead of just once. I'm thinking on reusing all of the excess water on a small container garden I want to start on my roof, so it doesn't all go to waste.

[Ray]

Originally Posted by Zoren

As usual Ray you are correct...I'll use Tiger Woods answer to almost every thing 'It's a process' (before you ask--No, not a golfer--but I do like Tiger).
I just got in some hydrocorn LECA (well 32 lbs.). I rinsed some and put it into a plastic bucket with 2 gallons of water with as you have suggested 2 teaspoons of Epson Salt--I will let it soak probably till Wendsday morning---and then I will rinse it again and leave in the bucket with water till I'm ready to use it. Should I put any root stimulant in the water with the soaking LECA? Ray, I'd like your opinion about adding Hydrogen Peroxide to the rinsing and soaking process. If you think it is a good idea how much should be added per gallon of water?
The manufacturer has instructions on the bag for cleaning the Hydrocorn . Looking forward to you answers and your opinions...Zoren...

Again, as been suggested several times already, the "KISS" principle applies here.

LECA is fired at about 2500F or higher, so certainly is sterile. I see no use for hydrogen peroxide. Rinse to remove dust, soak to remove soluble salts use daily in the manufacturing process. Adding Epsom Salts to the soak accelerates that process and leaves nutrients behind.

Adding a root growth stimulant helps get a plant established faster, so I always use it at transplanting.

Originally Posted by marcmaubert

Ok, I'll try to flood twice a week during the growing season instead of just once. I'm thinking on reusing all of the excess water on a small container garden I want to start on my roof, so it doesn't all go to waste.

Good idea! Just don't use it n on their orchids, as that's a great way to share pathogens.

[Zoren]

Good morning marcmaubert, I've just started S/H growing recently , so I'm experimenting and taking in ALL the advice, good/bad and any criticism so that I can learn more. I will be flooding my plants at every watering to see how effective this type of scheduled watering/feeding works for me, as long as all my plants are healthy I will use the fertilized water that I've mixed on all my plants. I will also try to remember not to add root stimulator only once a month or as needed and not mix the different stimulators in the same mixture. I'm guessing that I would still add fertilizer the the once a month mixtures. If I'm wrong I'm open to other suggestions. Thank you marcmaubert for your comments, we'll talk again

---------- Post added at 09:03 AM ---------- Previous post was at 08:47 AM ----------

Good morning Ray, sorry I missed your reply on how you water/feed your orchids, I will be trying this way of watering I can see the logic behind this method. I also have to thank you for explaining that I was over stimulating my plants by mixing different root stimulants with my MSU fertilizer at every watering. I should have realized that this mixture wasn't correct and it would cause me problems in the near future of plant growth. Thank you again..Zoren...

[estación seca]

Realize it's fine to water plants in S/H daily. In my experience they are healthier the more often I water them.

[Zoren]

Thank you Ray and estacion seca for your input.
I went back over what Ray said about Preparing LECA Media and it seems I've done it wrong, again. Fortunately I've used up all the media I had, hopefully my putting Kelp, Superthrive and MSU into my soaking solution (I usually prepare a bucket of LECA and let it soak until I'm ready to use it) will not cause me any problems with the newly potted plants. I asked before about PH of my water, should I bring the PH down?
Ray I've asked this question before, but for some reason I just seem not understand how much MSU (or any other fertilizer) into the water to attain as you recommend 35 ppm N. I use tap water I don't know how much Nitrogen is in my water. So as an example: if my water has a TDS of 145 ppm before I put the MSU in and I put say 1/4 teaspoon/gallon as recommended and take another reading and the TDS meter now says 200 ppm doses that mean that I now have 45 ppm more Nitrogen as I had before. I'm positive that I'm looking at this Nitrogen feeding of my plants all wrong. Do I have to find out how much Nitrogen is in my tap water to attain the proper levels. I would really appreciate as much of an explanation as possible, thanking you in advance..Zoren.

[estación seca]

First, don't get worried. This isn't that complicated. Many people grow orchids very well in LECA without any equipment beyond a bucket and a set of measuring spoons, never knowing what is in their water.

What you have done with the LECA is fine. The idea is to first, wash out dust; second, soak to remove sodium salts from the clay. The other stuff you added won't cause trouble, but won't help, either. Add those to water used for the plants.

There should be no nitrogen in municipal tap water. All the nitrogen comes from your fertilizer. Nitrates in water are contaminants from livestock urine and feces. You can get your water report from your water utility, if you haven't already. It will tell you pH, TDS or hardness and the composition of minerals in your water.

If you use the fertilizer calculator on the First Rays Web site you will easily be able to dose your plants. It's under Free Information.

Your pH is fine for orchids.

Inexpensive "TDS" meters don't measure TDS. I strongly recommend you not use one for this purpose.

ECC meters likewise don't measure the concentration of anything in the water, just the number of charged particles.

Inexpensive TDS meters, and ECC meters, measure electrical conductivity, which is proportional to the number of charged particles in the water. If you don't know what ions are in the water, and in what proportions, you don't have any idea how to convert the conductivity to TDS. The TDS meter has been adjusted to somebody's idea of standard tap water. If your tap water is has different minerals, or in different amounts, you reading will be wrong.

Inexpensive "TDS" and ECC meters are essentially useless to gardeners, except to compare the concentrations of two solutions of the same solute dissolved in the same water. This is how commercial farms use them. If you know your TDS meter's reading when you have the proper concentration of your fertilizer in your water, you can use your TDS meter to achieve the same concentration of the same fertilizer the next time you mix it up.

There are a lot of videos available showing people mixing fertilizer with ECC and TDS machines. They are just trying to impress people by using meters the viewers don't understand. Nobody needs more than a water report, a bucket and a set of measuring spoons.