{"product_id":"limestone-powder","title":"Limestone - Powder (-100 mesh)","description":"\u003cp dir=\"ltr\"\u003e\u003cspan\u003eLimestone (Fine Powder) is a finely ground calcitic limestone that reacts quickly in the soil to raise pH and supply plant-available calcium. Ground to pass 100 mesh, it carries far more surface area than coarse or granular grades, so it breaks down and neutralizes soil acidity within the current growing season instead of over several years.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp dir=\"ltr\"\u003e\u003cspan\u003eThis grade is built for growers who need a response now: correcting acidic potting mixes and living soils, setting pH before a planting, or topping up calcium in containers and raised beds. It is the same high-purity Canadian limestone as our coarse grade, ground fine for speed and even blending.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp dir=\"ltr\"\u003e\u003cspan\u003eCalcium plays a critical role in plant development, supporting strong cell walls, healthy root growth, and overall plant resilience.\u003c\/span\u003e\u003c\/p\u003e\n\u003ch2 dir=\"ltr\"\u003e\u003cspan\u003eBenefits \u003c\/span\u003e\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli dir=\"ltr\" aria-level=\"1\"\u003e\u003cspan\u003eFast-acting: the fine grind reacts within the current growing season\u003c\/span\u003e\u003c\/li\u003e\n\u003cli dir=\"ltr\" aria-level=\"1\"\u003e\u003cspan\u003eAdds calcium for strong, healthy plant growth\u003c\/span\u003e\u003c\/li\u003e\n\u003cli dir=\"ltr\" aria-level=\"1\"\u003e\u003cspan\u003eRaises and stabilizes soil pH quickly\u003c\/span\u003e\u003c\/li\u003e\n\u003cli dir=\"ltr\" aria-level=\"1\"\u003e\u003cspan\u003eImproves the availability of phosphorus\u003c\/span\u003e\u003c\/li\u003e\n\u003cli dir=\"ltr\" aria-level=\"1\"\u003e\u003cspan\u003eLow in magnesium compared to dolomitic lime, ideal where magnesium is already adequate\u003c\/span\u003e\u003c\/li\u003e\n\u003cli dir=\"ltr\" aria-level=\"1\"\u003e\u003cspan\u003eBlends evenly into potting soils, living soils, and container media\u003c\/span\u003e\u003c\/li\u003e\n\u003cli dir=\"ltr\" aria-level=\"1\"\u003e\u003cspan\u003eSupports beneficial soil microbial activity\u003c\/span\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2 dir=\"ltr\"\u003e\u003cspan\u003eFine Powder vs. Coarse Limestone \u003c\/span\u003e\u003c\/h2\u003e\n\u003cp dir=\"ltr\"\u003e\u003cspan\u003eParticle size controls how fast limestone works. This fine powder grade has a very high surface area, so it reacts quickly and is best suited to fast pH correction, blending into soil mixes, and container growing.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp dir=\"ltr\"\u003e\u003cspan\u003eOur\u003c\/span\u003e\u003ca href=\"https:\/\/www.optimizeorganics.ca\/collections\/optimize-organics-now-available\/products\/coarse-limestone-calcium\"\u003e\u003cspan\u003e \u003c\/span\u003e\u003cspan\u003ecoarse grade\u003c\/span\u003e\u003c\/a\u003e\u003cspan\u003e breaks down slowly and is better for long-term, slow-release conditioning in the field. Choose fine for speed and uniform blending. Choose coarse for long-term soil maintenance.\u003c\/span\u003e\u003c\/p\u003e\n\u003ch2 dir=\"ltr\"\u003e\u003cspan\u003eBest Uses \u003c\/span\u003e\u003c\/h2\u003e\n\u003ch3 dir=\"ltr\"\u003e\u003cspan\u003ePotting Mixes \u0026amp; Living Soils \u003c\/span\u003e\u003c\/h3\u003e\n\u003cp dir=\"ltr\"\u003e\u003cspan\u003eFine limestone blends evenly through peat, coir, and compost-based mixes. It corrects the natural acidity of peat and coir and sets a stable pH before planting, which makes it a standard component in living soil builds.\u003c\/span\u003e\u003c\/p\u003e\n\u003ch3 dir=\"ltr\"\u003e\u003cspan\u003eContainers \u0026amp; Raised Beds \u003c\/span\u003e\u003c\/h3\u003e\n\u003cp dir=\"ltr\"\u003e\u003cspan\u003eIn smaller soil volumes, even distribution matters. The fine grind spreads uniformly through the mix, so every part of the root zone gets consistent calcium and pH support.\u003c\/span\u003e\u003c\/p\u003e\n\u003ch3 dir=\"ltr\"\u003e\u003cspan\u003eFast pH Correction \u003c\/span\u003e\u003c\/h3\u003e\n\u003cp dir=\"ltr\"\u003e\u003cspan\u003eWhen a soil test shows low pH and you need results this season, fine limestone acts faster than coarse or granular grades.\u003c\/span\u003e\u003c\/p\u003e\n\u003ch2\u003e\u003cspan\u003eApplication \u003c\/span\u003e\u003c\/h2\u003e\n\u003ch3 dir=\"ltr\"\u003e\u003cspan\u003ePotting Mix \u0026amp; Living Soil Blending \u003c\/span\u003e\u003c\/h3\u003e\n\u003cp dir=\"ltr\"\u003e\u003cspan\u003eBlend 3 to 6 g per litre of mix (about 0.5 to 1 cup per cubic foot, or 5 to 10 lbs per cubic yard). Use the lower end for coir-based mixes and the higher end for heavily peat-based mixes. Mix thoroughly and moisten before planting.\u003c\/span\u003e\u003c\/p\u003e\n\u003ch3 dir=\"ltr\"\u003e\u003cspan\u003eGarden \u0026amp; Small Areas \u003c\/span\u003e\u003c\/h3\u003e\n\u003cp dir=\"ltr\"\u003e\u003cspan\u003eApply 500 g to 1 kg per 10 m² (1 to 2 lbs per 100 ft²) based on soil test results. Incorporate into the soil where possible. The fine grade begins reacting within the current growing season.\u003c\/span\u003e\u003c\/p\u003e\n\u003ch3 dir=\"ltr\"\u003e\u003cspan\u003eField Application (Agricultural Use) \u003c\/span\u003e\u003c\/h3\u003e\n\u003cp dir=\"ltr\"\u003e\u003cspan\u003eApply 1 to 2 tons per acre depending on soil conditions and pH levels. Incorporate before planting for the fastest, most uniform response.\u003c\/span\u003e\u003c\/p\u003e\n\u003ch3 dir=\"ltr\"\u003e\u003cspan\u003eSoil pH Management \u003c\/span\u003e\u003c\/h3\u003e\n\u003cp dir=\"ltr\"\u003e\u003cspan\u003eMost plants prefer a soil pH between 6.0 and 7.0. Because fine limestone reacts quickly, it can be used to correct pH ahead of or close to planting. Retest after one season to confirm results before reapplying.\u003c\/span\u003e\u003c\/p\u003e\n\u003ch2 dir=\"ltr\"\u003e\u003cspan\u003eSoil Testing Recommended \u003c\/span\u003e\u003c\/h2\u003e\n\u003cp dir=\"ltr\"\u003e\u003cspan\u003eLimestone application should be based on soil conditions. Applying without testing can lead to over-liming, which may reduce nutrient availability.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp dir=\"ltr\"\u003e\u003cspan\u003eOur\u003c\/span\u003e\u003ca href=\"https:\/\/www.optimizeorganics.ca\/products\/lab-analysis\"\u003e\u003cspan\u003e \u003c\/span\u003e\u003cspan\u003elaboratory soil analysis\u003c\/span\u003e\u003c\/a\u003e\u003cspan\u003e includes sampling, detailed results, and tailored application recommendations, so you know exactly what your soil needs and how much to apply.\u003c\/span\u003e\u003c\/p\u003e\n\u003ch2 dir=\"ltr\"\u003e\u003cspan\u003eUnderstanding Soil pH, Calcium, and Heavy Metals \u003c\/span\u003e\u003c\/h2\u003e\n\u003cp dir=\"ltr\"\u003e\u003cspan\u003eAluminum is naturally present in most soils, but under acidic conditions it dissolves into a form that plants can absorb. In this soluble form, aluminum damages root tips, limiting growth, water uptake, and nutrient access.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp dir=\"ltr\"\u003e\u003cspan\u003eApplying limestone supplies calcium and raises soil pH, which makes aluminum and other heavy metals far less available to plants. The result is deeper, stronger roots that use nutrients more efficiently.\u003c\/span\u003e\u003c\/p\u003e\n\u003ch2 dir=\"ltr\"\u003e\u003cspan\u003eHow Calcium Helps Limit Heavy Metal Uptake \u003c\/span\u003e\u003c\/h2\u003e\n\u003cp dir=\"ltr\"\u003e\u003cspan\u003eCalcium reduces heavy metal uptake in three key ways:\u003c\/span\u003e\u003c\/p\u003e\n\u003cp dir=\"ltr\"\u003e\u003cspan\u003e1. Raising Soil pH\u003c\/span\u003e\u003cspan\u003e In acidic soils, metals are more soluble and easier for plants to absorb. Limestone helps keep more of these metals bound in the soil rather than entering the plant.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp dir=\"ltr\"\u003e\u003cspan\u003e2. Competing at the Root Level\u003c\/span\u003e\u003cspan\u003e Calcium shares the same uptake pathways as metals like cadmium, lead, and nickel. When sufficient calcium is present, plants absorb more calcium and less of these competing metals.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp dir=\"ltr\"\u003e\u003cspan\u003e3. Strengthening Root Systems\u003c\/span\u003e\u003cspan\u003e Calcium fortifies cell walls and root membranes, helping roots better regulate what enters the plant and reducing passive uptake of unwanted elements.\u003c\/span\u003e\u003c\/p\u003e\n\u003ch2 dir=\"ltr\"\u003e\u003cspan\u003eHeavy Metals Most Affected \u003c\/span\u003e\u003c\/h2\u003e\n\u003cp dir=\"ltr\"\u003e\u003cspan\u003eImproving soil pH and calcium levels can help reduce the availability and uptake of:\u003c\/span\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli dir=\"ltr\" aria-level=\"1\"\u003e\u003cspan\u003eCadmium (Cd)\u003c\/span\u003e\u003c\/li\u003e\n\u003cli dir=\"ltr\" aria-level=\"1\"\u003e\u003cspan\u003eLead (Pb)\u003c\/span\u003e\u003c\/li\u003e\n\u003cli dir=\"ltr\" aria-level=\"1\"\u003e\u003cspan\u003eNickel (Ni)\u003c\/span\u003e\u003c\/li\u003e\n\u003cli dir=\"ltr\" aria-level=\"1\"\u003e\u003cspan\u003eZinc (Zn)\u003c\/span\u003e\u003c\/li\u003e\n\u003cli dir=\"ltr\" aria-level=\"1\"\u003e\u003cspan\u003eAluminum (Al)\u003c\/span\u003e\u003c\/li\u003e\n\u003cli dir=\"ltr\" aria-level=\"1\"\u003e\u003cspan\u003eManganese (Mn)\u003c\/span\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2 dir=\"ltr\"\u003e\u003cspan\u003eWhy This Matters \u003c\/span\u003e\u003c\/h2\u003e\n\u003cp dir=\"ltr\"\u003e\u003cspan\u003eHealthy soil is about balance, not just nutrients. By supplying calcium and improving soil pH, limestone helps create a more stable soil environment where plants can grow efficiently, access nutrients, and limit the uptake of unwanted elements, supporting cleaner, healthier crops.\u003c\/span\u003e\u003c\/p\u003e\n\u003ch2 dir=\"ltr\"\u003e\u003cspan\u003eTypical Analysis \u003c\/span\u003e\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli dir=\"ltr\" aria-level=\"1\"\u003e\n\u003cspan\u003eCalcium Carbonate (CaCO₃):\u003c\/span\u003e\u003cspan\u003e 97.38%\u003c\/span\u003e\n\u003c\/li\u003e\n\u003cli dir=\"ltr\" aria-level=\"1\"\u003e\n\u003cspan\u003eCalcium (Ca):\u003c\/span\u003e\u003cspan\u003e 39%\u003c\/span\u003e\n\u003c\/li\u003e\n\u003cli dir=\"ltr\" aria-level=\"1\"\u003e\n\u003cspan\u003eMagnesium (Mg):\u003c\/span\u003e\u003cspan\u003e 0.43\u003c\/span\u003e\u003cspan\u003e%\u003c\/span\u003e\n\u003c\/li\u003e\n\u003cli dir=\"ltr\" aria-level=\"1\"\u003e\n\u003cspan\u003eParticle size:\u003c\/span\u003e\u003cspan\u003e minus 100 mesh (99% passing 100 mesh, 95% passing 200 mesh)\u003c\/span\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp dir=\"ltr\"\u003e\u003cspan\u003eHigh-purity calcitic limestone with a high neutralizing value and low magnesium content.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp dir=\"ltr\"\u003e\u003ca href=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0087\/1022\/5979\/files\/OPTIMIZE-ORGANICS-LIMESTONE-FLOUR-_-100_Mesh_-COA.pdf?v=1783462416\"\u003e\u003cspan\u003e[DOWNLOAD - FINE LIMESTONE LAB ANALYSIS (PDF)\u003c\/span\u003e\u003c\/a\u003e\u003c\/p\u003e\n\u003cp dir=\"ltr\"\u003e\u003ca href=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0087\/1022\/5979\/files\/OPTIMIZE-ORGANICS-LIMESTONE-ORGANIC-DECLARATION.pdf?v=1775755341\"\u003e\u003cspan\u003eDOWNLOAD - ORGANIC DECLARATION LIMESTONE (PDF)\u003c\/span\u003e\u003c\/a\u003e\u003c\/p\u003e\n\u003cp dir=\"ltr\"\u003e\u003cspan\u003eThis product complies with Canada's Organic Production Systems General Principles and Permitted Substances Lists (CAN\/CGSB-32.310-2026, CAN\/CGSB-32.311-2026). Approved for use in organic production.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e \u003c\/p\u003e","brand":"Optimize Organics Inc","offers":[{"title":"1KG","offer_id":51935310414112,"sku":null,"price":11.0,"currency_code":"CAD","in_stock":true},{"title":"2KG","offer_id":51935310446880,"sku":null,"price":14.0,"currency_code":"CAD","in_stock":true},{"title":"10KG","offer_id":51935310479648,"sku":null,"price":39.0,"currency_code":"CAD","in_stock":true},{"title":"20KG","offer_id":51935310512416,"sku":null,"price":59.0,"currency_code":"CAD","in_stock":true},{"title":"22.7KG PAIL","offer_id":51935310545184,"sku":null,"price":89.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0087\/1022\/5979\/files\/1kg-limestone-powder-100-mesh-optimize-organics_2b217f6f-60e2-495a-83cc-07898fd2e165.webp?v=1783377532","url":"https:\/\/www.optimizeorganics.ca\/products\/limestone-powder","provider":"Optimize Organics Inc","version":"1.0","type":"link"}