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

OSA★28 - 4oz (120ml) - 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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Showing reviews 1-10 of 13 | Next

  1. It's great. 5 Star Review

    Posted by on Sep 1st 2017

    Noticed the difference in plants health.

  2. Products great! 4 Star Review

    Posted by on Jul 6th 2017

    The osa28 product is far superior to any related product

  3. Love 4 Star Review

    Posted by on Feb 16th 2017

    This is a great product to show love to your garden

  4. osa28 5 Star Review

    Posted by on Jan 21st 2017

    Great costumer support, my first order of osa28 was lost in the mail and sent me out a new bottle without delay so I can use it my garden. Will definitely be a return costumer!

  5. Great product. 5 Star Review

    Posted by on Dec 30th 2016

    Been using this OSA28. Makes a big difference and is a really great product.

  6. Noticeably difference on strain I've been growing for almost 10 years. 5 Star Review

    Posted by on Aug 5th 2016

    Noticeably thicker stem structure and much tighter nodal structure. Almost seemingly able to feed a lot heavier doses. Seems to finish faster by at least a week to a week and a half.

  7. Awesome for Guerilla's 5 Star Review

    Posted by on Apr 17th 2016

    This is a must have for all u other guerilla growers out there. this is a must have to stop insects,bud rot and wind damage. i still use potassium silica but only for a emulsifier of my neem oil. if u can only afford 1 silica source then this is the product u want.

  8. OSA/28 stems and drought stress 5 Star Review

    Posted by on Apr 5th 2016

    I like to monster crop super crop it all. I can definitely tell my stems are 100 times stronger I really have to push down to loosen the stems and sometimes that does work and the drough stress my plants were real dry and the leaves were still sitting up happy as ever. I also like the low application rates no silicate can beat it hands down the best!!!

  9. Does what it advertises. Great product. 4 Star Review

    Posted by on Apr 5th 2016

    I had recently transplanted a new batch of babies and they had a little shock going. Within 4 hours of feeding with OSA 28, they looked on the road to recovery. It's nice to have a product live up to the hype. I'll be buying the big bottle next time!

  10. This is bomb! 5 Star Review

    Posted by on Mar 30th 2016

    This is the best silica product on the market and even better then price. These guys are very cool and will help u anyway they can. i will always support this product bc it makes my ladys stack nodes on top of one another. When u look at the price of this compared to others like powerSI and fasilitor u will see Osa/28 is the truth. it works just as well or better imo then the other guys products. im a lifelong supporter of this company because the products are super concentrated!

Showing reviews 1-10 of 13 | Next

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