Need some help with S/H

[Jerry Delaney]

After seeing all of the posts here and other forums, I have decided to give S/H a go. Kind of hard after growing the "conventional" way for 30 some years. I have some questions that I am sure that the S/H growers can help me with.

1. TDS - I am some what concerned about my tap water for S/H. The TDS of my tap water will vary from a low of ~150 ppm to 230 ppm. I do not use RO and have no problem with salt build up but have observed in the past where the TDS were much higher that salt build up is usually worse with completely inorganic mediums. With this level of TDS should I be concerned about salt build up?

2. Fertilizer - I will most likely be using Technigro 17-5-24 Plus. This fertilizer does not contain a Calcium source. With the TDS levels mentioned above, do I need to add a Calcium supplement?

3. pH - The pH of my tap water is in the high 8's. At 100-125 ppm of N, the pH after running through the porportioner is 6.7-6.8. I think I would prefer it to be around 6.0 (any comments about this pH?). Does anyone out there adjust the pH down and if so what do you use?

4. My collection is quite mixed (I suffer from "one of" disease) but heavy into Catts, intergeneric Oncidiums, and Phrags.

Any guidance will be greatly appreciated. Thank you.

[brookn]

Jerry I wish I could help, but I am a newbie to s/h, and some of that is more technical than I get lol. I am sure Jay will come along soon though! Good luck.

[jay]

Ph, TDS, and Fertilizers.

Ph - The ideal Ph for hydroponics is "generally" 5.8-6.5. The reason I say generally is that there are some orchids that grow on limestone cliffs that would like a slightly higher Ph. The Ph of 8.0 is much too high. When we plant in bark, it works as a buffer to lower the overall Ph. With the inorganic LECA we need to make sure the water supply is adjusted. I use Ph up or Ph down from the local hydroponic store.

TDS/Fertilizer - 100-125 ppm is not that bad. Just be careful that you do not mix the fertilizer too high or it will create problems. There is probably some calcium in your water, but you could always use a little epsom salts every once in a while to give them calcium and magnesium sulfate. I do use RO water and mix my fertilizer so that the Nitrogen is at 125 ppm, which makes the whole solution somewhere around 200-225 ppm.


I hope this helps. Sorry I couldn't get back sooner, I was out of town at a wedding.

[LLW]

I have almost all of my orchids in semi-hydro. Now I don't have an extensive collection, but the 25+ I have in semi hydro all are loving it. I did not get real technical, I just sorta "jumped in" because it seemed a solution to my chronic bad habit of overwatering. Here in South Texas our water is so hard it clanks when it comes out of the tap, yet as long as I flush the pots out with running water at least every two or three weeks I have had no real problem. I use a weak solution of balanced fertilizer and a very generous application of worm tea. My Phals, Catts and Oncs. are really thriving. My Paphs seem happy, but I can't say hey are blooming all over the place, but I think that is because of a light issue. All I can say is I have had good luck and like I said I just "jumped in". For reference the Phal I have in my Avatar is a bloom in semi-hydro. Lashelle

[Jerry Delaney]

Thanks Jay & Lashelle for the information. I had already converted some of the plants & watered them once but wasn't too worried about a single watering doing any harm. As it is, with the information I gained from here and other places, I don't think I will change anything from what I did on the first watering. I have converted about 120 plants to S/H from about 20 different genera. I will keep you posted as to progress (or the lack there of). How long have the two of you been growing S/H? Once again, thanks for the info.