Do you keep your Superthrive in the refrigerator ???

[phal-newbie]

Just bought a 4oz bottle of Superthrive at Home Depot.
.....about $11.00........I plan to use for the first time on my phal noids that I have repotted from moss into bark....1 drop per gallon. I know I should store the bottle out of the light, but do you keep yours in the refrigerator between waterings ? I have heard this may improve the shelf life. Also, I have heard not to use on blooming phals........is this ccorrect ???
Thanks for all the help....sure love OB...........

[BobInBonita]

Short answer - I don't keep mine either in the dark or in the refrigerator.

Theoretical answer - most if not all organic reactions will be slowed by lowering the temperature (that's great for vitamins and hormones), but many inorganic solutions at or near concentration will crystallize and/or precipitate if you lower the temperature (bad for minerals). To complicate it further, if things precipitate, the pH can shift and that can change reaction rate.... blah, blah, blah.

Practical answer - Home Depot didn't refrigerate it, and the label doesn't say to refrigerate it anywhere I can find.

Psychological answer - if it makes you feel better and doesn't hurt anyone, why not do it.

Experimental answer - wait until your bottle is almost empty and refrigerate the remainder in a clear glass container (so you can see what happens). If it gets cloudy, crystallizes, or precipitates - you have your answer (don't refrigerate) and post your results here so we all know. If it doesn't do those things, refrigerating will probably extend your shelf life.

[phal-newbie]

Thanks Bob.....great answer.........I will do as you suggest.......................................It may be a long time till the bottle is almost empty, as there are MANY drops in 4oz. How about if I take a small amount from the new bottle and put that in the refrigerator NOW and watch for results ???.......quicker answer???

[CTB]

Sounds good, I keep mine in a cabinet, so I assume it's in the dark, no problem with it.

[Ray]

The synthetic rooting hormones are not particularly stable. They degrade rapidly upon exposure to light and/or heat - hence the brown bottle.

Exposed to direct sun, the hormone will decompose in a matter of minutes. At room temperature, about 6 months, warmer = shorter, colder = longer. Refrigerated, about a year or longer.

The fact that HD does not refrigerate it does not mean it shouldn't be. You also don't know how old it is when you get it!. I buy and resell Dyna-Gro K-L-N instead of ST because you get more "bang for the buck" in terms of hormone content. I buy it fresh and keep it refrigerated until shipping.

Concerning blooming phals - if you feed your phals a tablespoon per gallon at every watering, the flowers will likely be deformed. At a drop per gallon, don't worry about it.

[phal-newbie]

Thanks Ray,,,,,,,,You have helped me lots since I joined OB. Everyone should sign up for your newsletter.

[Call_Me_Bob]

i keep mine with my ferts, kinda dark, not exceptionally hot

[Shirley]

I keep a small amount handy in my orchid room and keep the larger bottle in the fridge. Just refill the small bottle when necessary. Easy, peasy!