UPDATE Phals and Oncidium orchid in semi-hydro

[Dorsetman]

Dorstman, I clean my hydroton with a pressure hose to remove all the dust a couple of times, and then soak it for 24 hours prior to use.

Do you measure the conductivity or pH in any way ?

[empiref]

Do you measure the conductivity or pH in any way ?

Nope, I have no instrument for measuring the PH.
It's a little bit too technical for me, however, I use Aspirin 50mg per liter of water after flushing the pots when I water, and I heard that regulates the PH due to the acetylsalicylic acid.

[Dorsetman]

Nope, I have no instrument for measuring the PH.
It's a little bit too technical for me, however, I use Aspirin 50mg per liter of water after flushing the pots when I water, and I heard that regulates the PH due to the acetylsalicylic acid.

It would make it more acid if you call that regulation - but suppose you want it less acid ?

[empiref]

It would make it more acid if you call that regulation - but suppose you want it less acid ?

Well...I have to start praying then!
There's nothing more I can do.

[AtantaR]

I had a delivery of 100 litres of Hydroton this week, looked a little dusty - i put it in buckets with good rain water, and after 24 hours the water gave a reading off the scale - which goes up to EC 4000 !. After three changes of water its now down to just over 1000 - so maybe another two changes it will be ready for use. But do beware anyone using this stuff - it can be very fiery indeed !

Speaking of Electrical Conductivity (EC) and total dissolved solids (TDS). Geoff, Have you found specific EC readings in PPM that works best for your orchids? Is this something that you always take readings on while making a nutrient solution or monitoring one?

[Dorsetman]

Nope, I have no instrument for measuring the PH.
It's a little bit too technical for me, however, I use Aspirin 50mg per liter of water after flushing the pots when I water, and I heard that regulates the PH due to the acetylsalicylic acid.

Further thought ; would one aspirin in a litre make any discernible difference I wonder ? I might have made the experiment out of curiosity, but we don't keep aspirin in the house ( paracetamol is our stock equivalent).

[empiref]

Further thought ; would one aspirin in a litre make any discernible difference I wonder ? I might have made the experiment out of curiosity, but we don't keep aspirin in the house ( paracetamol is our stock equivalent).

It's 50 mg of aspirin (acetylsalicylic acid) in one liter of water. if your tablet is 300 mg of acetylsalicylic acid, that means you'll dissolve it in 6 liters of water. I've read a study while researching that was published by the AOS in 2001, but can't seem to find it now.

[Dorsetman]

Speaking of Electrical Conductivity (EC) and total dissolved solids (TDS). Geoff, Have you found specific EC readings in PPM that works best for your orchids? Is this something that you always take readings on while making a nutrient solution or monitoring one?

I hope I am not guilty of teaching grandma to suck eggs (!)…
TDS and EC and the relationship between them are often misunderstood. Much of what I say here can be found on the web-site of the Hanna Company byw, who make an awful lot of meters. TDS cannot be measured directly. EC can be measured ( or to be more precise, electrical resistance is easily measured) using a bridge circuit, and as it happens, EC ( electrical conductivity) is the precise reciprocal of electrical resistance. As one falls, the other rises and so on. So the meter takes that reading and expresses it as EC.
Then if it is a TDS meter, it uses a constant K to multiply the EC reading and calls the answer TDS .
The problem is that some meters use a constant of 1.2, others 1.5, and so on. I had a Dutch meter which used 2.0 ; currently I have a Hanna HI9813 which I think uses 1.5 and another Hanna HI98129 which uses 1.6. ( I can tell you why, but its irrelevant to this matter).
If I were to tell you what TDS I use for my nutrients I would have to add which meter – and when am writing for a publication, editors think that is being pedantic ! But if I quote EC, it doesn’t matter what meter you use, the reading is the same.
The required EC depends upon the compost ; inorganic need higher for obvious reasons. Summer need higher too . So my ranges vary from EC 250 to 750 ( these are in microSiemens or it may be milliSiemens – I forget which – but most recommended orchid fertilisers mixed up to makers instructions in pure,i.e. rain water or good RO water will give about 500 or 600. If giving 50 or 60 the reading is in the other one of the two. Both are fractions of Siemens – one is thousandths, the other hundredths.)
Btw – there are exceptions to these figures – very thin leaved orchids like Eulophia guineense will show leaf burn at these strengths , and often I just use rain water alone.

[mootattoo1]

Looks good! I have an Onc. hybrid I bought & transferred straight to s/h. I don't think it could be happier!

[AtantaR]

hows everything going with this johnny? I have also put some of my oncidium alliance and Phalaenopsis into semi-hydro. My Beallara's are doing well but i seem to have problems with my phals. I have to keep the hydroton on the drier side by drilling holes in the very bottom of my container. Just wondering on a update. thanks