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  • OSA★28 Plant Available Silicon (Original) - High Powered Silicon Fertilizer

OSA★28 - 8oz (250ml) - Silicic Acid

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Product Description

OSA★28 Plant Available Silicon (as monosilicic acid) strengthens cell walls, increases nutrient uptake, and helps plants handle all kinds of stresses. Other silicates are not bioavailable and take time+microbes to become plant available. This makes OSA★28 the fastest option for delivering silicon directly into the plant cell walls! Silicon also has a synergy with calcium in building better plant structure. Many growers see increased calcium response when feeding with OSA★28.

Silicon is the second most abundant element in the earth's crust. It is now known to be essential for optimal plant growth, health and production. Silicon in the soil isn't available (as various silicates). Plants can only absorb silicon as monosilicic acid (individual molecules). Orthosilicic acid is the stabilized form that transforms into monosilicic acid when mixed in clean water. Silicon chemistry is quite tricky so purity of ingredients and manufacturing excellence are necessary to get a stable and effective product to you.

OSA★28 is manufactured in-house by our staff Ph.D chemists in the USA with domestically sourced ingredients. This means lower cost, fresher product, and more quality control. Monosilicic acid is tricky to make since it requires complex reactions to produce a stable product. OSA★28 is shelf-stable and has higher concentrations than competitive products but at a much lower cost.

Usage rates
Root drench: Mix 0.5ml per gallon of water every feeding from early vegetative through mid-bloom
Foliar spray: Mix 4-8ml per gallon of water 1-2 times per week

Shelf Life
2 years when stored properly -- Seal after use and store in a cool dark place

This bottle mixes 120 gallons of feed water!

Other Details

Gallons Mixed:
Shelf Life:
2 years

Product Reviews

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  1. Already noticing results 5 Star Review

    Posted by on Jul 12th 2017

    This stuff is great. Only a few weeks and my girls are already showing the results. This product is the truth.

  2. Best of the best 5 Star Review

    Posted by on Dec 20th 2016

    Used several Silicas on the market and this is probably the best one on the market currently. Stalks are thick as hell especially with the combination of ColonyX and Deep6. Expensive product but worth every penny in my opinion.

  3. Best Silicic I've ever used 5 Star Review

    Posted by on Jun 22nd 2016

    The plants love it. You can see the difference within 24 hrs. No problem with up take. Works great with Osa 28. I've had great results with every strain I've used it on.

  4. From floppy wimp to beast 5 Star Review

    Posted by on May 11th 2016

    I grow in organic soil that I mix myself. One of my best strains struggled in this soil when I switched from synthetic nutes. It went from being a beast to a floppy wimp. I started OSA 28 during the last week in veg and by week 2 in flower it started growing straight up with the stems turning from a purple to a lime green. There was no other change in my system except this change from Agsil 16 to OSA 28. I'm not easily impressed but this product is the truth. Looking forward to the results when starting from day 1 with OSA 28.

  5. Awesome 5 Star Review

    Posted by on Apr 14th 2016

    Love this stuff!

  6. best bang for your buck 5 Star Review

    Posted by on Mar 3rd 2016

    I have grown some of the thickest stalks in the shortest amount of time.

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