Pros and Cons of Grodan rock wool mini cubes

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How do you punch the holes in your pots? And where do you get the deep clear pots?
Hello southernbelle, The pot in the photo is a one quart freezer/soup container. My wife has been packing leftovers in them for my son for years. I stole a few and used them for sundews (Drosera) and Paphs. More recently, I saw Jason Fischer recommending them for Phrags and they work well. Check out his blog for kovachii. For even larger plants, the tall seven inch white Hydro pots work well, or the one gallon Plant Warrior pots. The holes are made with a soldering iron. I put a just couple holes in the sides almost halfway up, and a few in the bottom. I use a fan to be sure the fumes are directed away from me.

Cheers,
Paul
 

PeteM

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How do you punch the holes in your pots? And where do you get the deep clear pots?
Also... I need to find out how you grow a field of Sarrenicia like that. I have a few in small pots, they look kind of scrawny on their own.. do you use a shallow tray or deep tub? any tips would be much appreciated!
 
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To me growstone and perlite seem pretty much the same except for size. How else are they different?
Growstone does not crush, perlite does potentially. However, growstone is pretty sharp. I didn't like soaking it, so switched. It also sticks to roots, much like bark, whereas perlite does not tend to as much. I have a lot of it, but plan to use it (unless someone wants it) in the garden to deter voles. Vole Bloc is a similar product that is expanded slate and totally inert, no rinsing, although it does leach dust. They don't like to scratch their noses when burrowing... Anyway, I have actually purchased cattleyas from Krull-Smith potted in (what appeared to be) Vole Bloc and nothing else.
 
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"Also... I need to find out how you grow a field of Sarrenicia like that. I have a few in small pots, they look kind of scrawny on their own.. do you use a shallow tray or deep tub? any tips would be much appreciated!"

I'm using plastic wading pools. Lots of cp growers around here use them. They attract mosquitoes, of course, so I add Mosquito Bits to kill the larvae. Interestingly, I recently discovered dragonflies are breeding in the pools.

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Cheers,
Paul
 
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littlefrog

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I might have missed something, did you imply that you grow drosera in rockwool? I'm actually looking for a new CP medium. Never thought about rockwool...

Rob
Hello southernbelle, The pot in the photo is a one quart freezer/soup container. My wife has been packing leftovers in them for my son for years. I stole a few and used them for sundews (Drosera) and Paphs. More recently, I saw Jason Fischer recommending them for Phrags and they work well. Check out his blog for kovachii. For even larger plants, the tall seven inch white Hydro pots work well, or the one gallon Plant Warrior pots. The holes are made with a soldering iron. I put a just couple holes in the sides almost halfway up, and a few in the bottom. I use a fan to be sure the fumes are directed away from me.

Cheers,
Paul
 

PeteM

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Growstone does not crush, perlite does potentially. However, growstone is pretty sharp. I didn't like soaking it, so switched. It also sticks to roots, much like bark, whereas perlite does not tend to as much. I have a lot of it, but plan to use it (unless someone wants it) in the garden to deter voles. Vole Bloc is a similar product that is expanded slate and totally inert, no rinsing, although it does leach dust. They don't like to scratch their noses when burrowing... Anyway, I have actually purchased cattleyas from Krull-Smith potted in (what appeared to be) Vole Bloc and nothing else.

Vole Bloc... will look this up! Thanks
 

Sky7Bear

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I have most of my orchids at present in one of a variety of semi-hydroponic mixes, all rock based (leca and monto clay mostly), and suspect that growing in rock wool is similar, though I haven't experimented lately. The advantage, of course, is that the medium doesn't rot, though pH change or salt buildup can be an issue if not cared for. However, I wonder, in the case of all orchid growing, including these, that we've forgotten what the "old growers" seemed to know--that lots of air at the roots was as important as enough water, and that the air/water balance is not the same for all genera in all media. I know that just adding an upside down net basket to the bottom and more holes to the sides seems to encourage good root growth, and too high a percentage of water in whatever medium is being used leads to rot (the primary disadvantage of all of the organic media, I think). Rands seemed to know this with his pots, as did the growers with the short terra cotta pots with slits on the lower sides. Perhaps the "Goldilocks principle applies-not too wet, not too dry, but just right.
 

Ray

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FWIW, I just repotted a couple of plants using Grodan Mini-cubes.

Warczatorea Heaven’s Bank went into straight cubes in an Air-Cone pot and Pescatorea Sandra’s First went into 50/50 cubes and LECA. Both have always done well for me in straight sphagnum, but I got tired of changing it out every 6 months or so, and believe it or not, it dried very rapidly indoors over the winter.

My “gut feel” Is that the 50/50 mix will be my longer-term preference as it will stay airier, but I’m trying to keep an open mind about the straight stuff.
 

SouthPark

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Perhaps the "Goldilocks principle applies-not too wet, not too dry, but just right.

In general ------ definitely --- something like that. The old 'sweet spot' or 'sweet region' or 'suitable range' way of thinking. Otherwise ----- the other schools of growing, such as hydroponics ----- where some help may be needed too, such as aerating the water to keep the oxygen levels up at satisfactory levels.
 

sergeharvey

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I have switched a few Phrags (bessae hybrids) to Grodan minicubes/large perlite in a 4 to 1 ratio and the roots are growing like mad. I will further evaluate in a couple of months. Salinity ranges about 200.
 

NYEric

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I use grow cubes and moss on the top of the mix with stolonous Phrags. The roots grow on top of and around the cubes.

Pete M. showing off the Habs! :p
 

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I use grow cubes and moss on the top of the mix with stolonous Phrags. The roots grow on top of and around the cubes.

Pete M. showing off the Habs! :p
Update, favorable results so far... waiting for one of the cubes to jump up and snap off the spike. ;)
IMG_6237.JPG


Also, I new this summer Ophrys 'bee' orchids (2 different species) from the Tarzane Group orchids. I have no experience with these and.. lovingly threw the two dry little tubers into the magic cubes. I see a little green emerging from both pots.. Very much looking forward to thisIMG_6238.JPG .
 
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