Decided to foliar spray with power SI at .5mL/1L RO H2O. Didn’t ph just went ahead and applied. Not sure if I messed up? Any advice is appreciated. Hope my seedlings are ok tomorrow morning 
following are images right after spraying
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Si is highly alkaline, but if you don’t see any damage then don’t worry about it.
The only time a plant should be sprayed with anything is if the grower is applying fungicide or pesticide. Spraying invites more problems than it can potentially help.
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I’ve been foliar spraying tribus mix (.7mL/32oz H2O) pretty much daily and just did the first foliar spray of power SI original; read thy some users see crazy ph changes with power si and became worried. Thanks for your feedback.
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I never feed Si until I get to flowering. Applying it too early strengthens plant cell structure (e.g. a stiff plant) and can make it difficult to train the plant without damaging it.
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Thanks for your advice; so I just checked the power si og ph mix I had made and it was at 3ph; added ph up and overshot to 7.8ph so ended up adding another .5mL of power si and now ph reads at 6.8ph.
I don’t ph my tribus blend and checked it this morning it’s at 5.8ph;
Plants are looking great right now, a little top heavy hence why I added power Si.
Power SI original is derived from urea, phosphoric acid, potassium silicate, sodium molybdate hence the acidic ph.
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Most Si products are straight potassium silicate, which is very alkaline.
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With the potassium Silicate I use, I bring the PH down to 5.5 - 5.8 with liquid Fulvic Acid when applying as a foliar spray on my indoor plants. i only start applying at least a few weeks into veg. Plants love it and can see the results almost immediately. Also i only apply in "afternoons " or a few hours before lights out as Si is taken up better later in the plants day.
But these are the guidelines as stipulated by my hydro supplier…
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This is interesting; after I run out of monosilicic acid I need to try that (seems like a better alternative economically); currently I plan on only applying power si once/week as a foliar spray then whatever is left over from the 32oz pour it to the roots. Might take me a while to run out of power SI.
This is my first grow since 2009 and my second grow period. Thanks for the tip that is one I plan on using in the future.
Indeed! I sprayed my plants as a brand new grower many years ago based on internet advice and ended up getting white powdery mildew. I took a hard stance against any foliar feeding or spraying and haven’t had a single mold, mildew, or rot issue ever since!
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We’ve seen a host of problems come up over the years resulting from foliar spraying. It’s just not worth it.
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