You are viewing all Organic Growers Supply products related to “Rock Powders.”
Tired of ineffectively mixing fertilizers or potting soil ingredients together in a wheelbarrow or tractor bucket? Let us do the dirty work for you! Buy ingredients from us or bring your own.
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Biochar helps your soil sequester more carbon and emit less nitrous oxide. Also provides a dream home for beneficial bacteria and fungi, while preventing essential nutrients from leaching away.
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Soil Testing & Organic Fertilizer Recommendation Service
out-of-stock, Unavailable for 2024
Soil Amendments and Fertilizers
out-of-stock, Unavailable for 2024
Don’t guess—test! You’ll learn your soil pH, organic matter percentage, levels of common minerals and nutrients, plus we’ll offer customized recommendations to correct or impro
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North Country Organics® Bone Char
currently on backorder
Animal-based -
Soil Amendments and Fertilizers
currently on backorder
NPK: 0-16-0. Provides large amounts of readily available phosphorus. A most economical source of P for deficient soils. May be applied without restrictions to organically certified fields.
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Pro Pelleted Calcitic Limestone
currently on backorder
Calcium Source -
Soil Amendments and Fertilizers
currently on backorder
The most common and most frequently used soil conditioner. also called Hi-Cal lime. Recommended for soils with excess magnesium.
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Pro Pelleted Limestone, Dolomitic Limestone Pro-Select Prill
currently on backorder
Calcium Source -
Soil Amendments and Fertilizers
currently on backorder
The least expensive liming agent. Use to sweeten soil (raise pH) and provide calcium where excess magnesium is not a problem.
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Silicon is linked to improved yields, especially recommended for cannabis, orchard crops, cucurbits, sweet corn, grains and forage crops. Also helps build resistance to powdery mildew.
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Formulated to build humus, enhance CEC, and condition the soil in which the ancient roots reside, whether they be abandoned heirlooms or wild seedlings. Can be applied in fall or spring.
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A blend of granite meal, K-Mag, sulfur, Tennessee brown rock, compost, peat, and Azomite. Brings down the soil pH and provides the nutrients necessary for healthy blueberry plants and good fruit.
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Fall Fruit Tree Prep Mix
currently on backorder
Fedco's Fertilizer Mixes -
Soil Amendments and Fertilizers
currently on backorder
For a deluxe tree planting spot, choose this mix! Contains a broad spectrum of macro and micronutrients and soil conditioners that fruit trees thrive on. Follow our directions for use in the fall.
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A balanced fertilizer to keep your bearing fruit trees healthy and productive. If your tree put on 4" or less of terminal growth last year, our Fruition Mix will put new spring in its step!
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Hole-Istic Spring Planting Mix
currently on backorder
Fedco's Fertilizer Mixes -
Soil Amendments and Fertilizers
currently on backorder
Recommended for fruit trees at planting time. Our own well-balanced blend of Tennessee brown phosphate, alfalfa meal, Azomite, and K-Mag in a humus-rich base of worm castings.
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Sleepytime Garden Blend
currently on backorder
Fedco's Fertilizer Mixes -
Soil Amendments and Fertilizers
currently on backorder
Spread this blend of granite, zeolites, gypsum, micronutrients and humates in that fall, and it will improve soil structure, remineralize, and enhance nutrient availability for the next spring!
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NPK: 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 critters.
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Soluble borate for fluid fertilizers and nutrient sprays. Boron is essential for all stages of tree growth and fruit set. Powder mixes easily in any spray solution.
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Contains over 67 minerals beneficial to plants and animals. A mix or particle sizes. Lots of powder, but still less dusty than Micronized Azomite.
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Contains over 67 minerals beneficial to plants and animals, including rare earth elements.
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A paramagnetic stone powder for remineralizing and enhancing general foundational soil fertility.
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Natural phosphorus source. Adequate phosphorus results in more vigorous early root formation, better flower and seed production, better growth in cold temperatures, and better water use efficiency.
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Contains about 5% potassium in very slow-release form. Can be added to the soil in large amounts without altering the pH. Greatly enhances soil structure and promotes healthier plants.
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A powerful soil restoration amendment! Supports plant health and increases yields by facilitating roots’ uptake of plant nutrients and water. Improves levels of carbon and humus.
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A good source of immediate potassium for depleted soil and of magnesium where calcium is abundant. Alliums like its sulfur and potatoes like its quick boost of potassium.
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Magnesium is a building block of chlorophyll and therefore essential to efficient photosynthesis. May boost yields significantly, especially for roses and tomatoes.
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Recommended by soil gurus Phil Callahan and Mark Fulford. Lowest concentration of heavy metals of any phosphate source. Concentrations of available phosphate were regularly over 6% when tested.
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Agricultural Sulfur. Use to make soil pH more acidic. Often helpful for both lowbush and highbush blueberries, and for potatoes. Lowering the pH of gravel paths will help control weed growth.
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Zeolites can improve the productivity of any texture of soil, improving water and mineral retention in sandy soils and improving aeration and minimizing compaction in heavier soils.
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