Rock Powders - Supplies

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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. read more

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Ancients Rise Mix

Fertilizer Blend

currently on backorder

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. read more

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Blueberry Booster

Fertilizer Blend

currently on backorder

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. read more

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Fall Fruit Tree Prep Mix

Fertilizer Blend

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. read more

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Fruition Mix

Fertilizer Blend

currently on backorder

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! read more

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Hole-Istic Spring Planting Mix

Fertilizer Blend

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. read more

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Sleepytime Garden Blend

Fertilizer Blend

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! read more

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Vegemighty

Fertilizer Blend

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. read more

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20 Mule Team Borax Solubor® DF

Mineral

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. read more

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AZOMITE®, Field Grade Natural Trace Minerals

Contains over 67 minerals beneficial to plants and animals. A mix or particle sizes. Lots of powder, but still less dusty than Micronized Azomite. read more

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AZOMITE®, Granulated Natural Trace Minerals

Contains over 67 minerals beneficial to plants and animals, including rare earth elements. read more

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BrixBlend Basalt

Mineral

A paramagnetic stone powder for remineralizing and enhancing general foundational soil fertility. read more

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Granite Meal

Mineral

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. read more

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Hum-Amend Max

Mineral

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. read more

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Monterey Epsom Salts

Mineral

Magnesium is a building block of chlorophyll and therefore essential to efficient photosynthesis. May boost yields significantly, especially for roses and tomatoes. read more

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ZeoMax Garden Aid

Mineral

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. read more

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Aragonite

pH and Calcium

From oyster shells, not pulverized rock. Aragonite is even lower than calcitic lime in magnesium, so it's the ideal choice for soils with excessive magnesium. read more

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Gypsum, Pelletized

pH and Calcium

A good source of calcium when the soil pH is already at a desired level. read more

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Pro Pelleted Calcitic Limestone

pH and Calcium

The most common and most frequently used soil conditioner. also called Hi-Cal lime. Recommended for soils with excess magnesium. read more

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Pro Pelleted Limestone, Dolomitic Limestone Pro-Select Prill

pH and Calcium

The least expensive liming agent. Use to sweeten soil (raise pH) and provide calcium where excess magnesium is not a problem. read more

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Tiger Organic 90CR Sulfur

pH and Calcium

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. read more

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Wollastonite

pH and Calcium

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. read more

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North Country Organics® Bone Char

Single Ingredient Nitrogen

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. read more

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Fertoz Organic Granulated Rock Phosphate Fertilizer

Single Ingredient Phosphorus

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. read more

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Phosphate, Tennessee Brown Rock

Single Ingredient Phosphorus

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. read more

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K-Mag Granular Trio 0-0-22

Single Ingredient Potassium

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. read more

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Protassium+® Sulfate of Potash 0-0-50

Single Ingredient Potassium

NPK: 0-0-50. The most economical source of available potassium! Fine-grained texture. read more

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Custom Mixing

Service

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. read more

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Soil Testing & Organic Fertilizer Recommendation Service

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 read more

Organic Growers Supply: Rock Powders