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OSA/28 provides stabilized silicic acid that instantly transforms into plant-usable form upon dilution with water. When you combine OSA/28 with other indoor growing supplements you will find that you can achieve a better yield in both quantity and quality.

  • Strengthens cell walls and increases nutrient uptake in plants.
  • Provides silicic acid in a form available to the plant to uptake.
  • Size:

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HTG Supply is committed to providing you with the very best products, pricing and service in the industry. We will ship your order fast and discreetly packaged to protect your privacy. Buy with confidence knowing your HTG Supply purchase includes simple returns as well as lifetime product support. Call our team of real growing experts with your purchasing or product use questions, and we will be here to help!

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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.

Indoor growing supplements like OSA/28 are manufactured by Plant Science Concepts’ staff of Ph.D. chemists in the USA using domestically sourced ingredients.

Indoor Growing Supplement 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



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