You are viewing all Organic Growers Supply products related to “Rock Powders.”
If you’re tired of ineffectively mixing fertilizers or potting soil ingredients together in a wheelbarrow or tractor bucket, let us do the dirty...
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Join the carbon-farming revolution. Biochar is the product of heating organic matter in a low-oxygen environment: instead of releasing the carbon...
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Don’t guess—test! Applying fertilizers and soil amendments without the guidance of a professional soil test is like driving downtown with your...
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(0-16-0, 32% P2O5, approx. 30% Ca) Burned bone meal provides large amounts of readily available phosphorus. The most economical source of P for
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(Sodium Tetraborate, 20.5% B) Soluble borate for fluid fertilizers and nutrient sprays. Boron is essential for all stages of tree growth and fruit...
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(0-0-52) The most economical source of available potassium. Moderate to fast-release. If your soil has sufficient magnesium, this is the potassium...
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(33% CaCO3) When the price of aragonite spiked a few years ago, we tried to steer growers toward the chemically identical Calcitic Limestone, but...
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(0-0-0.2, 1.8% Ca) Named for its A-to-Z of Minerals including Trace Elements; contains over 67 minerals beneficial to plants and animals.
A mix of
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(0-0-0.2, 5% Ca) Named for its A-to-Z of Minerals including Trace Elements; contains over 67 minerals beneficial to plants and animals.
A mix of
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(0-0-0.2, 5% Ca) Named for its A-to-Z of Minerals including Trace Elements; contains over 67 minerals beneficial to plants and animals, including...
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(49.3% SiO2, 13.3% Al2O3, 9.2% CaO, 5.7% MgO, plus trace minerals) A paramagnetic stone powder from the Pioneer Valley of Massachusetts for...
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(0-7-0, 20% total Phosphate, plus at least 30% Ca and 10% SiO2. Natural phosphorus source from mines in British Columbia, Montana, and Mexico....
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Contains about 5% potassium in very slow-release form. Plants need potassium for sugar and starch production. Granite meal can be added to the...
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(Calcium Sulfate CaSO4•2H2O, 21% Ca, 16% S) Gypsum is a good source of calcium when the pH is already at a desired level. The sulfur in gypsum...
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Max out your soil health! This is a powerful soil restoration amendment designed to raise your soil’s cation exchange capacity while adding high...
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(10.8% Mg, 22% S) Langbeinite is a marine deposit of potassium sulfate and magnesium sulfate in soluble form. A good source of immediate potassium...
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(9.8% water-soluble Mg, 12.9% S) Magnesium is a building block of chlorophyll and therefore essential to efficient photosynthesis. In...
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(0-3-0, 21-25% total P2O5) 40% CaO. The consistency of rich soil. Comes from the washing piles left behind when high-grade ore was extracted to...
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Pro-Select Prill (87% CaCO3, 7% MgCO3). Cal Carb Equivalent 95.8%. The most common and most frequently used soil conditioner. Calcitic is the...
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Pelleted Dolomitic Limestone (57.7% CaCO3, 33% MgCO3). Cal Carb Equivalent 96.9%. The least expensive liming agent. Use to sweeten soil (raise pH)...
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Agricultural Sulfur. 90% elemental sulfur, 10% bentonite clay. Use to lower soil pH (make it more acidic). Often helpful for both lowbush and...
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(48% CaO and 52% SiO2). Cal Carb Equivalent 76.0%. Soluble-grade and at least 95% pure (may contain trace amounts of iron, manganese and...
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Zeolites are aluminosilicate lattices, derived from volcanic ash, that hold up to 55% of their weight in water in the small cavities of their...
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Whether they be abandoned heirlooms or wild seedlings, tucked in the woods or growing alongside an old road, apple trees live on for hundreds of...
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A blend of Granite Meal, K-Mag, sulfur, Tennessee brown rock, Penobscot Blend Compost & Peat, and Azomite. Brings down the soil pH and provides...
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To prepare your land in fall or winter for spring fruit-tree planting, use this mix. Without digging a hole, spread one bag on an area 4–6' in...
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Recommended for fruit trees at planting time. Formerly known as Fruit Tree Planting Mix. Our own well-balanced blend of Tennessee brown phosphate,...
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The last of the root vegetables have been tucked into the cellar, and the soil microbes snooze contentedly under a blanket of young winter rye....
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(3.4-2.2-3.5) An excellent all-purpose fertilizer for those who prefer to avoid animal products. Great for flower bulbs because it won’t attract...
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