{"product_id":"liquid-gypsum","title":"Liquid Gypsum for Clay Soil \u0026 Lawns","description":"\u003c!-- Dr Forest — Liquid Gypsum Product Page (v2 — Design System v1.0, prefix drf-lg-) --\u003e\n\u003cstyle\u003e\n  .drf-wrap *, .drf-wrap *::before, .drf-wrap *::after { box-sizing: border-box; margin: 0; padding: 0; }\n  .drf-wrap { font-family: 'Jost', sans-serif; font-weight: 400; color: #2c2c2c; font-size: 14px; line-height: 1.65; width: 100%; max-width: 100%; overflow: hidden; }\n  :root {\n    --drf-grn:        #1B3D2F;\n    --drf-grn-dark:   #0F2A1F;\n    --drf-grn-light:  #E8F0EB;\n    --drf-grn-mid:    #4a7a5e;\n    --drf-cream:      #F5F2EC;\n    --drf-gold:       #C5A55A;\n    --drf-gold-light: #FAF7F0;\n    --drf-muted:      #3A4A40;\n    --drf-white:      #FFFFFF;\n    --drf-border:     #d4cfc5;\n  }\n\n  \/* ── TYPOGRAPHY ── *\/\n  .drf-wrap h2 { font-family: 'Cormorant Garamond', serif; font-weight: 400; font-size: 1.9em; color: var(--drf-grn); line-height: 1.25; margin-bottom: 0.5em; 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}\n  .drf-refs h4 { color: var(--drf-muted); }\n  .drf-refs ol { padding-left: 1.4em; margin: 0; }\n  .drf-refs li { margin-bottom: 0.3em; }\n  .drf-sep { border: none; border-top: 1px solid var(--drf-gold); width: 200px; margin: 1.8em auto; }\n\n  \/* ── TABLE (dark-green header, alternating pale-green stripes) ── *\/\n  .drf-wrap table { width: 100%; border-collapse: collapse; margin: 1em 0; font-size: 0.92em; }\n  .drf-wrap table th { background: var(--drf-grn); color: #fff; font-weight: 600; padding: 0.6em 0.8em; text-align: left; font-size: 0.85em; letter-spacing: 0.04em; }\n  .drf-wrap table td { padding: 0.55em 0.8em; border-bottom: 1px solid var(--drf-border); }\n  .drf-wrap table tr:nth-child(even) td { background: var(--drf-grn-light); }\n\n  \/* ── FIGURES (optional — inline SVG charts) ── *\/\n  .drf-fig { margin: 1.2em 0 1.4em; border: 1px solid var(--drf-border); border-top: 2px solid var(--drf-gold); background: var(--drf-white); padding: 1em 1em 0.8em; }\n  .drf-fig svg { width: 100%; height: auto; display: block; }\n  .drf-fig-cap { font-size: 0.8em; color: var(--drf-muted); line-height: 1.55; margin-top: 0.7em; }\n  .drf-fig-cap strong { color: var(--drf-grn); }\n\u003c\/style\u003e\n\n\u003c!-- ===== 4-TAB BODY (Overview \/ The Science \/ How to Use \/ FAQ) ===== --\u003e\n\u003cdiv class=\"drf-wrap\"\u003e\n\u003cdiv class=\"drf-tabs-wrap\"\u003e\n\u003cinput type=\"radio\" name=\"drf-lg-tabset\" id=\"drf-lg-tab1\" checked\u003e \u003cinput type=\"radio\" name=\"drf-lg-tabset\" id=\"drf-lg-tab2\"\u003e \u003cinput type=\"radio\" name=\"drf-lg-tabset\" id=\"drf-lg-tab3\"\u003e \u003cinput type=\"radio\" name=\"drf-lg-tabset\" id=\"drf-lg-tab4\"\u003e\n\u003cdiv class=\"drf-tab-labels\"\u003e\n\u003clabel for=\"drf-lg-tab1\"\u003eOverview\u003c\/label\u003e \u003clabel for=\"drf-lg-tab2\"\u003eThe Science\u003c\/label\u003e \u003clabel for=\"drf-lg-tab3\"\u003eHow to Use\u003c\/label\u003e \u003clabel for=\"drf-lg-tab4\"\u003eFAQ\u003c\/label\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"drf-panels\"\u003e\n\n\u003c!-- ═══════════ TAB 1 — OVERVIEW ═══════════ --\u003e\n\u003cdiv class=\"drf-panel\" id=\"drf-lg-panel1\"\u003e\n\u003cspan class=\"drf-eyebrow\"\u003eMade by Growers · Backed by Science\u003c\/span\u003e\n\u003ch2\u003eLiquid gypsum for clay soil and lawns\u003c\/h2\u003e\n\u003cdiv class=\"drf-badge-row\"\u003e\n\u003cspan class=\"drf-badge drf-badge-green\"\u003e19.55% Calcium\u003c\/span\u003e \u003cspan class=\"drf-badge drf-badge-green\"\u003e15.31% Sulphur\u003c\/span\u003e \u003cspan class=\"drf-badge drf-badge-gold\"\u003e5 Micron Average Particle\u003c\/span\u003e \u003cspan class=\"drf-badge drf-badge-green\"\u003eNaturally Mined\u003c\/span\u003e \u003cspan class=\"drf-badge drf-badge-green\"\u003eNo Change to Soil pH\u003c\/span\u003e \u003cspan class=\"drf-badge drf-badge-dark\"\u003ePacked in Stockport\u003c\/span\u003e\n\u003c\/div\u003e\n\u003cp\u003e\u003cstrong\u003eLiquid gypsum is micronised calcium sulphate held in suspension\u003c\/strong\u003e so you can water it onto clay soil and lawns without digging. As it dissolves it puts calcium into the surface water, which helps clay that disperses hold together instead of sealing — and it feeds calcium and sulphur without changing soil pH the way lime does. The Dr Forest version is mined mineral suspended in fulvic acid, with no synthetic dispersants. It is thick and settles on standing: shake hard before every use.\u003c\/p\u003e\n\u003cp\u003eIt will not fix waterlogging from compaction, a high water table, or missing drains. If water sits because it has nowhere to go, no bottle will change that. A crumb of dry soil in a glass of rainwater tells you in a day whether your clay disperses; the How to Use tab has that test plus screwdriver, hole and ribbon checks before you buy.\u003c\/p\u003e\n\u003cdiv class=\"drf-callout\"\u003e\n\u003cspan class=\"drf-callout-title\"\u003eRates at a glance\u003c\/span\u003e\n\u003cp\u003eRoot drench: 5 ml per litre (maintenance) or 10 ml per litre where a soil test shows calcium is genuinely low. Lawns: 10 ml per litre at 1 L\/m², or 15 ml per litre fortnightly for three months on dispersive clay, ideally from early autumn. On heavy clay you are actively improving, expect to come back about every three years.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"drf-callout\"\u003e\n\u003cspan class=\"drf-callout-title\"\u003ePets \u0026amp; children\u003c\/span\u003e\n\u003cp\u003eTreat as any garden concentrate: store out of reach, and keep pets and children off the area while you apply. Once a drench has soaked in or a spray has dried, we know of no reason to keep them off. We do not describe this product as certified organic.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"drf-stats\"\u003e\n\u003cdiv class=\"drf-stat\"\u003e\n\u003cspan class=\"drf-stat-number\"\u003e19.55%\u003c\/span\u003e\u003cspan class=\"drf-stat-label\"\u003eCalcium (Ca) · 27.35% CaO\u003c\/span\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"drf-stat\"\u003e\n\u003cspan class=\"drf-stat-number\"\u003e15.31%\u003c\/span\u003e\u003cspan class=\"drf-stat-label\"\u003eSulphur (S) · 38.23% SO₃\u003c\/span\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"drf-stat\"\u003e\n\u003cspan class=\"drf-stat-number\"\u003e5 μm\u003c\/span\u003e\u003cspan class=\"drf-stat-label\"\u003eAverage particle\u003c\/span\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"drf-stat\"\u003e\n\u003cspan class=\"drf-stat-number\"\u003eNo change\u003c\/span\u003e\u003cspan class=\"drf-stat-label\"\u003eTo soil pH\u003c\/span\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003ch3\u003eWhat is liquid gypsum used for in the UK garden?\u003c\/h3\u003e\n\u003cul class=\"drf-uses\"\u003e\n\u003cli\u003e\n\u003cstrong\u003eLiquid gypsum for clay soil\u003c\/strong\u003e — on clay that disperses in water, dissolving gypsum holds the surface together so rain soaks in. Watered on, no digging in.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eLiquid gypsum for lawns\u003c\/strong\u003e — calcium and sulphur into the root zone of established turf, and one of the few ways to reach the clay underneath without lifting the grass.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCalcium feed for fruiting crops\u003c\/strong\u003e — tomatoes, peppers, apples, pears, strawberries, courgettes and cucumbers, where a soil test shows calcium is genuinely low. Supplies calcium without raising pH the way lime does.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSulphur supply\u003c\/strong\u003e — sulphate-sulphur, available at once with no microbial conversion.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFoliar calcium\u003c\/strong\u003e — the micronised suspension can be filtered and sprayed for calcium straight through the leaf.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eWhy liquid gypsum rather than lime for calcium?\u003c\/h3\u003e\n\u003cdiv class=\"drf-compare\"\u003e\n\u003cdiv class=\"drf-compare-box\"\u003e\n\u003ch4\u003eLiquid gypsum (calcium sulphate)\u003c\/h4\u003e\n\u003cul\u003e\n\u003cli\u003eSupplies calcium without changing soil pH: Anderson and colleagues found no change in soil solution pH in a one-year and a ten-year trial [8]\u003c\/li\u003e\n\u003cli\u003eSupplies sulphate-sulphur at the same time\u003c\/li\u003e\n\u003cli\u003eDissolving gypsum raises the salt concentration of the surface water, which holds dispersive clay together\u003c\/li\u003e\n\u003cli\u003eMicronised to a 5 micron average, so it dissolves quickly and can be watered on rather than dug in\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"drf-compare-box\"\u003e\n\u003ch4\u003eAgricultural lime (calcium carbonate)\u003c\/h4\u003e\n\u003cul\u003e\n\u003cli\u003eRaises soil pH, which is only useful where acidity needs correcting\u003c\/li\u003e\n\u003cli\u003eSupplies no sulphur\u003c\/li\u003e\n\u003cli\u003eCan push an already-neutral soil above the range most vegetables want\u003c\/li\u003e\n\u003cli\u003eThe right choice when a soil is both acid and short of calcium\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"drf-callout drf-callout-dark\"\u003e\n\u003cspan class=\"drf-callout-title\"\u003eWhat liquid gypsum cannot fix\u003c\/span\u003e\n\u003cp\u003eGypsum works on \u003cstrong\u003eclay that disperses in water\u003c\/strong\u003e. It does nothing for waterlogging caused by mechanical compaction, a high water table, an impermeable subsoil pan, missing land drains or poor site grading. If water sits on your soil because it has nowhere to go, no liquid product will change that. The How to Use tab has four tests that tell you which problem you have before you spend anything.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"drf-callout\"\u003e\n\u003cspan class=\"drf-callout-title\"\u003ePacked in Stockport\u003c\/span\u003e\n\u003cp\u003eDr Forest is a small-batch business in Stockport, Greater Manchester. Other liquid gypsum questions are answered at \u003ca href=\"\/pages\/liquid-gypsum-faq\"\u003eliquid gypsum: your questions, answered\u003c\/a\u003e, and the case for and against it on British clay is set out in \u003ca href=\"\/blogs\/the-dr-forest-blog\/does-liquid-gypsum-work-on-clay-soil-guide\"\u003eliquid gypsum for clay soil, honestly assessed\u003c\/a\u003e. \u003cem\u003eMade by Growers. Backed by Science.\u003c\/em\u003e\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\n\u003c!-- ═══════════ TAB 2 — THE SCIENCE ═══════════ --\u003e\n\u003cdiv class=\"drf-panel\" id=\"drf-lg-panel2\"\u003e\n\u003cspan class=\"drf-eyebrow\"\u003eThe Science\u003c\/span\u003e\n\u003ch2\u003eHow does liquid gypsum work? Calcium, sulphate and the clay surface\u003c\/h2\u003e\n\u003ch3\u003eWhat it is, and what it is not for\u003c\/h3\u003e\n\u003cp\u003eThe science of gypsum on clay was originally worked out for salt-affected soils in Australia, the Mediterranean and the American west, where irrigation water has loaded the soil with sodium. UK gardens do not usually have a sodium problem, and that matters. On clay that does not disperse, the structural effect is modest and organic matter does the lasting work. Where clay genuinely disperses and caps, gypsum helps. No UK survey has measured how much British garden clay disperses, so the crumb-in-a-glass test in the How to Use tab is the honest answer.\u003c\/p\u003e\n\u003cp\u003eMilling gypsum to a 5 micron average particle is what makes it dissolve quickly; Chen and Dick note that gypsum has to be finely ground before it goes readily into solution [4]. We do not put a clock on it; that depends on your soil and your rainfall. Why it is a suspension rather than a solution is explained in \u003ca href=\"\/blogs\/the-dr-forest-blog\/what-is-liquid-gypsum-guide\"\u003ewhy liquid gypsum is a suspension, not a solution\u003c\/a\u003e.\u003c\/p\u003e\n\u003chr class=\"drf-sep\"\u003e\n\u003ch3\u003eComposition\u003c\/h3\u003e\n\u003ctable\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003cth\u003eComponent\u003c\/th\u003e\n\u003cth\u003eAnalysis\u003c\/th\u003e\n\u003cth\u003eForm\u003c\/th\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCalcium (Ca)\u003c\/td\u003e\n\u003ctd\u003e19.55% w\/v (27.35% CaO)\u003c\/td\u003e\n\u003ctd\u003eCa²⁺ from dissolving calcium sulphate\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSulphur (S)\u003c\/td\u003e\n\u003ctd\u003e15.31% w\/v (38.23% SO₃)\u003c\/td\u003e\n\u003ctd\u003eSulphate, plant-available without microbial conversion\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eAverage particle\u003c\/td\u003e\n\u003ctd\u003e5 microns\u003c\/td\u003e\n\u003ctd\u003eWet-milled natural gypsum\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCarrier\u003c\/td\u003e\n\u003ctd\u003eFulvic acid\u003c\/td\u003e\n\u003ctd\u003eThe liquid the gypsum is suspended in; not a dispersant\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eEffect on soil pH\u003c\/td\u003e\n\u003ctd\u003eNone measured\u003c\/td\u003e\n\u003ctd\u003eNeutral salt, not a liming material [4][8]\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003cp\u003eThe gypsum is quarried from natural rock rather than recovered as flue-gas or phosphogypsum by-product. We make no purity claim on the back of that: Kost and colleagues applied mined and flue-gas (FGD) gypsum at ten US field sites and found most response ratios, for yield and for elements in soil, crop tissue and water, sat close to 1.00 for both [7], and the Miller and Ben-Hur rainfall studies below both used phosphogypsum [2][3]. The difference is provenance and what else is in the bottle, which is covered in \u003ca href=\"\/blogs\/the-dr-forest-blog\/natural-vs-synthetic-gypsum\"\u003enatural vs synthetic gypsum: does the source matter?\u003c\/a\u003e\u003c\/p\u003e\n\u003cdiv class=\"drf-pullquote\"\u003eGypsum works on clay that comes apart in water. A crumb of your soil in a glass of rainwater tells you in a day whether yours does.\u003c\/div\u003e\n\u003ch3\u003eWhy water pools on clay\u003c\/h3\u003e\n\u003cp\u003eWhen a clay garden floods and stays wet for days, the problem is usually a skin a millimetre or two thick at the very surface. Clay particles carry a negative charge and push each other apart unless a positive ion sits between them as a bridge. Calcium does that job well. Sodium does it badly. Rain is close to distilled water, so it dilutes the surface solution towards the concentration below which a given clay stops holding together; the plates separate, wash into the pores and seal the top. Oster, Shainberg and Wood measured that threshold: calcium-saturated montmorillonite flocculates at 0.25 mol\u003csub\u003ec\u003c\/sub\u003e m⁻³, rising to 12 at full sodium saturation [1].\u003c\/p\u003e\n\u003ch3\u003eMechanisms of action\u003c\/h3\u003e\n\u003cdiv class=\"drf-mech\"\u003e\n\u003cspan class=\"drf-mech-num\"\u003e01\u003c\/span\u003e\n\u003ch4\u003eHolding the surface together\u003c\/h4\u003e\n\u003cp\u003eDissolving gypsum releases calcium and sulphate into the water lying on the soil and keeps its salt concentration above the line at which the clay disperses, so water soaks in instead of standing. This route does not need sodium to be present. Miller measured it on three non-sodic Georgia soils: surface gypsum roughly doubled final infiltration on two of them and cut soil loss by 30 to 50% [2].\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"drf-mech\"\u003e\n\u003cspan class=\"drf-mech-num\"\u003e02\u003c\/span\u003e\n\u003ch4\u003eCalcium onto the exchange\u003c\/h4\u003e\n\u003cp\u003eOver a longer period calcium from the dissolved gypsum swaps onto the clay in place of sodium, which lowers the concentration the clay needs to stay together. This half is conditional: it needs something worth displacing, so on a soil already dominated by calcium it changes little. The RHS advises against long-term watering with artificially softened water: softeners swap calcium and magnesium for sodium, and sodium can build up in the soil and affect its structure [10].\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"drf-mech\"\u003e\n\u003cspan class=\"drf-mech-num\"\u003e03\u003c\/span\u003e\n\u003ch4\u003eStronger on dispersive soils\u003c\/h4\u003e\n\u003cp\u003eBen-Hur and colleagues found surface gypsum cut soil loss \"sharply from the dispersive soils and moderately from the nondispersive soils\" [3]. Franzen, Rehm and Gerwing put the limit plainly: if soils are not dispersive, gypsum applications do not help infiltration, though it has reduced crusting in laboratory work on both sodic and non-sodic soil [5].\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"drf-mech\"\u003e\n\u003cspan class=\"drf-mech-num\"\u003e04\u003c\/span\u003e\n\u003ch4\u003eWhy it needs repeating\u003c\/h4\u003e\n\u003cp\u003eThe displaced sodium leaves as soluble sodium sulphate, and the same solubility that makes gypsum useful is why it does not stay put. Chen and Dick: gypsum \"may need to be reapplied every couple of years in wet climates or on irrigated fields as the gypsum will leach out of the soil profile\" [4]. In Ohio trials, annual or two-yearly applications did more good than one large dose, which lowered maize yield in one of four years [9].\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"drf-mech\"\u003e\n\u003cspan class=\"drf-mech-num\"\u003e05\u003c\/span\u003e\n\u003ch4\u003eCalcium and sulphur in the plant\u003c\/h4\u003e\n\u003cp\u003eCalcium is immobile in the plant: it moves up in the transpiration stream and cannot be pulled out of old leaves to supply new growth, so shortfalls show first in the fastest-growing tissue. Sulphur goes into cysteine, methionine and the proteins built from them. Fleuridor and colleagues measured gypsum raising sulphur in soil and crop tissue within five months of each application on fourteen organic dairy fields, with no short-term yield gain [6]. We hold no trial data on the fulvic acid carrier, so we claim nothing for it.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003chr class=\"drf-sep\"\u003e\n\u003cdiv class=\"drf-refs\"\u003e\n\u003ch4\u003eScientific references\u003c\/h4\u003e\n\u003col\u003e\n\u003cli\u003eOster, J.D., Shainberg, I. \u0026amp; Wood, J.D. (1980). Flocculation value and gel structure of sodium\/calcium montmorillonite and illite suspensions. \u003cem\u003eSoil Science Society of America Journal\u003c\/em\u003e, 44(5), 955–959.\u003c\/li\u003e\n\u003cli\u003eMiller, W.P. (1987). Infiltration and soil loss of three gypsum-amended Ultisols under simulated rainfall. \u003cem\u003eSoil Science Society of America Journal\u003c\/em\u003e, 51(5), 1314–1320.\u003c\/li\u003e\n\u003cli\u003eBen-Hur, M., Shainberg, I., Stern, R. \u0026amp; van der Merwe, A.J. (1992). Slope and gypsum effects on infiltration and erodibility of dispersive and nondispersive soils. \u003cem\u003eSoil Science Society of America Journal\u003c\/em\u003e, 56(5), 1571–1576.\u003c\/li\u003e\n\u003cli\u003eChen, L. \u0026amp; Dick, W.A. (2011). Gypsum as an agricultural amendment: general use guidelines. \u003cem\u003eOhio State University Extension\u003c\/em\u003e, Bulletin 945.\u003c\/li\u003e\n\u003cli\u003eFranzen, D., Rehm, G. \u0026amp; Gerwing, J. (2006). Effectiveness of gypsum in the north-central region of the U.S. \u003cem\u003eNDSU Extension Service\u003c\/em\u003e, SF-1321.\u003c\/li\u003e\n\u003cli\u003eFleuridor, L., Herms, C., Culman, S., Dick, W.A., Paul, P.A. \u0026amp; Doohan, D. (2021). Short-term responses of soils and crops to gypsum application on organic farms. \u003cem\u003eAgronomy Journal\u003c\/em\u003e, 113(5), 4220–4230.\u003c\/li\u003e\n\u003cli\u003eKost, D., Ladwig, K.J., Chen, L. et al. (2018). Meta-analysis of gypsum effects on crop yields and chemistry of soils, plant tissues, and vadose water at various research sites in the USA. \u003cem\u003eJournal of Environmental Quality\u003c\/em\u003e, 47(5), 1284–1292.\u003c\/li\u003e\n\u003cli\u003eAnderson, G.C., Pathan, S., Hall, D.J.M., Sharma, R. \u0026amp; Easton, J. (2021). Short- and long-term effects of lime and gypsum applications on acid soils in a water-limited environment: 3. Soil solution chemistry. \u003cem\u003eAgronomy\u003c\/em\u003e, 11(5), 826.\u003c\/li\u003e\n\u003cli\u003eRakkar, M. \u0026amp; LaBarge, G. (2024). Response of soils and crops to gypsum application in Ohio. \u003cem\u003eOhio State University Extension\u003c\/em\u003e, ANR-0153.\u003c\/li\u003e\n\u003cli\u003eRoyal Horticultural Society. Collecting, storing and reusing water (guidance on softened water).\u003c\/li\u003e\n\u003c\/ol\u003e\n\u003cp style=\"margin-top: 0.6em;\"\u003eFigures describe the published literature on gypsum and are not product-specific guarantees.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\n\u003c!-- ═══════════ TAB 3 — HOW TO USE ═══════════ --\u003e\n\u003cdiv class=\"drf-panel\" id=\"drf-lg-panel3\"\u003e\n\u003cspan class=\"drf-eyebrow\"\u003eHow to Use\u003c\/span\u003e\n\u003ch2\u003eHow to apply liquid gypsum: rates for plants, lawns and clay soil\u003c\/h2\u003e\n\u003cdiv class=\"drf-callout drf-callout-gold\"\u003e\n\u003cspan class=\"drf-callout-title\"\u003eShake well before every use\u003c\/span\u003e\n\u003cp\u003eThis is a thick mineral suspension, not a clear solution, and the micronised gypsum settles on standing. Shake or stir vigorously for at least 30 seconds before measuring. If the bottle has been sitting for an extended period, invert and shake several times before use. The thick, creamy texture when shaken is normal. Do not store in a pre-diluted form; always dilute fresh for each application. 1 tsp is 5 ml.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"drf-callout drf-callout-dark\"\u003e\n\u003cspan class=\"drf-callout-title\"\u003eHow often, and when in the year\u003c\/span\u003e\n\u003cp\u003eFrequencies sit alongside the rates below where one applies. The short version on timing: \u003cstrong\u003eSeptember to November is the main window, March to April the second\u003c\/strong\u003e, and between May and August use the feeding rates only. On heavy clay you are actively improving, expect to come back to it about every three years. Avoid frozen, snow-covered or saturated ground, where surface-applied material is more likely to run off than soak in. For the liquid-specific frequency question, see \u003ca href=\"\/pages\/how-often-to-apply-liquid-gypsum\"\u003ehow often and when should you apply liquid gypsum?\u003c\/a\u003e\u003c\/p\u003e\n\u003c\/div\u003e\n\u003ch3\u003eApplication rates: plants and beds\u003c\/h3\u003e\n\u003cdiv class=\"drf-rate\"\u003e\n\u003ch4\u003eRoot drench: general maintenance\u003c\/h4\u003e\n\u003cdiv class=\"drf-rate-meta\"\u003e\n\u003cstrong\u003eRate:\u003c\/strong\u003e 1 tsp (5 ml) per litre\u003c\/div\u003e\n\u003cp\u003eStandard rate for all plants during the growing season. Apply around the root zone, not over the crown, and water in well afterwards. Compatible with all Dr Forest fertilisers.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"drf-rate\"\u003e\n\u003ch4\u003eRoot drench: active deficiency or high demand\u003c\/h4\u003e\n\u003cdiv class=\"drf-rate-meta\"\u003e\n\u003cstrong\u003eRate:\u003c\/strong\u003e 2 tsp (10 ml) per litre\u003c\/div\u003e\n\u003cp\u003eThe corrective rate, where a soil test shows calcium is genuinely low, or for calcium-hungry crops such as tomatoes, peppers and apples during rapid fruit fill. Return to the standard rate afterwards.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"drf-rate\"\u003e\n\u003ch4\u003eFoliar spray: rapid correction\u003c\/h4\u003e\n\u003cdiv class=\"drf-rate-meta\"\u003e\n\u003cstrong\u003eRate:\u003c\/strong\u003e 5 ml per litre, through 200 micron mesh\u003c\/div\u003e\n\u003cp\u003eDelivers calcium directly through the leaf and fruit surface. Apply in early morning or evening and avoid full sun; the suspension may leave a white residue at higher rates. Filter through 200 micron mesh before use in fine spray nozzles.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"drf-rate\"\u003e\n\u003ch4\u003eSpot treatment: individual plants\u003c\/h4\u003e\n\u003cdiv class=\"drf-rate-meta\"\u003e\n\u003cstrong\u003eRate:\u003c\/strong\u003e 5 ml per litre at 200–500 ml per plant\u003c\/div\u003e\n\u003cp\u003eFor a single plant you want to feed calcium, apply directly around the root zone at the higher volume. The lawn clay-conditioning rate is specified for lawns, so we do not carry it across to borders and beds.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003ch3\u003eApplication rates: lawns and turf\u003c\/h3\u003e\n\u003cp\u003eLiquid gypsum puts calcium and sulphur into the root zone of established turf without digging, disruption or a change in soil pH. For a lawn sitting on clay that disperses, it is one of the few ways to reach that clay at all. More on the lawn case at \u003ca href=\"\/pages\/is-liquid-gypsum-good-for-lawns\"\u003eis liquid gypsum good for lawns?\u003c\/a\u003e It also comes paired with our wetting agent as the \u003ca href=\"\/products\/waterlogged-lawn-kit\"\u003eWaterlogged Lawn Kit\u003c\/a\u003e.\u003c\/p\u003e\n\u003cdiv class=\"drf-rate\"\u003e\n\u003ch4\u003eLawn: general maintenance\u003c\/h4\u003e\n\u003cdiv class=\"drf-rate-meta\"\u003e\n\u003cstrong\u003eRate:\u003c\/strong\u003e 10 ml per litre at 1 L\/m²\u003c\/div\u003e\n\u003cp\u003eStandard lawn rate for ongoing calcium and sulphur supply. Apply with a watering can fitted with a rose, or through a knapsack sprayer. Water in lightly after application. Calcium is a structural component of grass cell walls; the sulphur deepens green colour and supports protein synthesis in the leaf.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"drf-rate\"\u003e\n\u003ch4\u003eLawn: clay soil improvement\u003c\/h4\u003e\n\u003cdiv class=\"drf-rate-meta\"\u003e\n\u003cstrong\u003eRate:\u003c\/strong\u003e 15 ml per litre at 1 L\/m²  |  \u003cstrong\u003eFrequency:\u003c\/strong\u003e Fortnightly for three months\u003c\/div\u003e\n\u003cp\u003eHigher rate for lawns on clay that disperses, so the surface sits wet and puddles after rain. Dissolving gypsum holds the salt concentration in the surface water above the line at which the clay comes apart, and deeper down calcium swaps onto the clay in place of sodium, without disturbing the turf. Start the programme in early autumn where you can, so the gypsum is dissolving in the surface water before the winter rain that does the capping.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"drf-rate\"\u003e\n\u003ch4\u003eLawn: after aeration or scarifying\u003c\/h4\u003e\n\u003cdiv class=\"drf-rate-meta\"\u003e\n\u003cstrong\u003eRate:\u003c\/strong\u003e 10–15 ml per litre at 1 L\/m²  |  \u003cstrong\u003eFrequency:\u003c\/strong\u003e Immediately after aeration\u003c\/div\u003e\n\u003cp\u003eApply immediately after hollow-tine aeration, slit aeration or scarifying, while the open channels let the liquid reach the clay beneath the turf. To be straight about it: no trial compares gypsum applied through core holes with gypsum applied to the surface, and the surface-sealing mechanism arguably favours leaving it on top. Aerate because compaction needs aerating. Gypsum does not relieve compaction; a two-year Ohio study found no change in penetration resistance [9].\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"drf-callout\"\u003e\n\u003cspan class=\"drf-callout-title\"\u003eWhen to run the three-month lawn programme\u003c\/span\u003e\n\u003cp\u003eStart it in early autumn. Gypsum stops the surface sealing by holding dissolved calcium and sulphate in the water lying on the soil while rain is falling, so it needs to be down before the rain that does the damage rather than after it. In the north-west that means having it on from September. A spring start in March or April is the next best thing if autumn gets away from you. One caveat, because it is repeated everywhere as though settled: there is no field trial comparing autumn application with spring. The autumn case is reasoning from the mechanism, not a measured result.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003ch3\u003eRate table\u003c\/h3\u003e\n\u003ctable\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003cth\u003eSituation\u003c\/th\u003e\n\u003cth\u003eRate\u003c\/th\u003e\n\u003cth\u003eWhen \/ how\u003c\/th\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eRoot drench, maintenance\u003c\/td\u003e\n\u003ctd\u003e1 tsp (5 ml) per litre\u003c\/td\u003e\n\u003ctd\u003eGrowing season\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eRoot drench, deficiency or high demand\u003c\/td\u003e\n\u003ctd\u003e2 tsp (10 ml) per litre\u003c\/td\u003e\n\u003ctd\u003eWhere a soil test shows calcium is genuinely low, or for calcium-hungry crops during rapid fruit fill; then back to standard\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFoliar spray\u003c\/td\u003e\n\u003ctd\u003e5 ml per litre, 200 micron mesh\u003c\/td\u003e\n\u003ctd\u003eEarly morning or evening\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSpot treatment, single plant\u003c\/td\u003e\n\u003ctd\u003e5 ml per litre at 200–500 ml per plant\u003c\/td\u003e\n\u003ctd\u003eAround the root zone, at the higher volume\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eLawn, maintenance\u003c\/td\u003e\n\u003ctd\u003e10 ml per litre at 1 L\/m²\u003c\/td\u003e\n\u003ctd\u003eOngoing\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eLawn, clay improvement\u003c\/td\u003e\n\u003ctd\u003e15 ml per litre at 1 L\/m²\u003c\/td\u003e\n\u003ctd\u003eFortnightly for three months; start in early autumn where you can\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eLawn, after aeration\u003c\/td\u003e\n\u003ctd\u003e10–15 ml per litre at 1 L\/m²\u003c\/td\u003e\n\u003ctd\u003eImmediately after aeration\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003ch3\u003eStep-by-step preparation\u003c\/h3\u003e\n\u003col class=\"drf-steps\"\u003e\n\u003cli\u003e\n\u003cstrong\u003eShake the bottle thoroughly.\u003c\/strong\u003e Invert and shake vigorously for 30 seconds. The product is thick and creamy, which is normal for a mineral suspension. Never measure from an unshaken bottle.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMeasure into a splash of warm water first.\u003c\/strong\u003e Measure the required amount into a small jug or cup holding a little warm water and stir until the suspension is fully dispersed. The warm water lifts the mineral paste cleanly off the spoon and the jug.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAdd the concentrate to the rest of your water.\u003c\/strong\u003e Pour it into your watering can or spray container filled with the remaining volume and stir briefly. The suspension stays stable during normal use.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eApply to the root zone or foliage.\u003c\/strong\u003e For root drenches, apply evenly around the base and water in. For foliar, filter through fine mesh and apply in early morning or evening.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eUse fresh.\u003c\/strong\u003e Do not store diluted. Prepare only what you need for each application and use it immediately.\u003c\/li\u003e\n\u003c\/ol\u003e\n\u003ch3\u003eWill it help your drainage? Four tests before you buy\u003c\/h3\u003e\n\u003cp\u003eThere are three causes of a waterlogged garden and gypsum addresses one of them. Clay that disperses: yes. Mechanical compaction from foot traffic, machinery or building work: no, that needs deep forking, broadfork aeration, hollow-tine aeration or double-digging with organic matter, after which gypsum can help hold the clay against re-dispersing. No drainage outlet, whether a high water table, an impermeable subsoil pan, missing land drains or poor grading: no, that needs land drains, a French drain, a soakaway, regrading or raised beds to lift the growing zone above the water table. Applying liquid gypsum to soil that is wet because water has nowhere to go is a waste of product.\u003c\/p\u003e\n\u003col class=\"drf-steps\"\u003e\n\u003cli\u003e\n\u003cstrong\u003eThe screwdriver test (compaction).\u003c\/strong\u003e Push a long screwdriver into moist soil. In our experience, uncompacted soil lets it in 15 to 20 cm under moderate hand pressure. A hard, resistant layer within 5–10 cm is a compaction pan. This is a mechanical problem and gypsum will not fix it: fork, broadfork or hollow-tine aerate it first.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eThe dispersion test (clay that comes apart).\u003c\/strong\u003e Drop an air-dried crumb of soil from about 10 cm down into a glass of rainwater and read it at ten minutes and again at two hours. A milky halo spreading from the crumb is dispersion, and gypsum has a job to do. Full protocol: \u003ca href=\"\/pages\/does-liquid-gypsum-work-on-clay-soil\"\u003edoes liquid gypsum work on clay soil?\u003c\/a\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eThe hole test (drainage outlet).\u003c\/strong\u003e Dig a hole 30 cm deep and 30 cm wide in the problem area, fill it with water and time it. Water still sitting there after 24 hours means a high water table, a subsoil pan or no gradient. No liquid product will fix that; you need physical drainage.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eThe ribbon test (clay at all).\u003c\/strong\u003e Squeeze a lump of moist soil between thumb and forefinger into a flat ribbon. True clay forms a smooth, shiny ribbon 5 cm or longer. If you cannot form one, your drainage problem is unlikely to be clay-related. Look at subsoil panning, water table or surface grading instead.\u003c\/li\u003e\n\u003c\/ol\u003e\n\u003cdiv class=\"drf-callout drf-callout-gold\"\u003e\n\u003cspan class=\"drf-callout-title\"\u003eBlossom end rot and bitter pit: what we can and cannot say\u003c\/span\u003e\n\u003cp\u003eBlossom end rot is mainly a calcium transport and water-relations problem rather than a shortage of calcium in the soil, so steady watering matters more than any calcium product. Bitter pit is associated with low calcium in the fruit rather than in the soil, and the evidence for soil-applied calcium is thin. Gypsum is worth using where a soil test shows calcium is genuinely low. More in \u003ca href=\"\/blogs\/the-dr-forest-blog\/blossom-end-rot-tomatoes\"\u003eblossom end rot in tomatoes: what causes it, and how I stopped it\u003c\/a\u003e.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"drf-callout\"\u003e\n\u003cspan class=\"drf-callout-title\"\u003eWorks well combined with…\u003c\/span\u003e\n\u003cp\u003e\u003ca href=\"\/products\/granulated-gypsum-clay-breaker\"\u003eGranulated Gypsum\u003c\/a\u003e for digging into beds and borders by the square metre before planting, with the liquid for lawns and established plants; \u003ca href=\"\/products\/natural-wetting-agent-plants-organic-soap-nuts-aloe-vera-dr-forest\"\u003eNatural Wetting Agent\u003c\/a\u003e where a clay lawn has dried into a crust that sheds water and the liquid is sitting on top; and \u003ca href=\"\/products\/organic-amino-chelated-calcium\"\u003eAmino Chelated Calcium\u003c\/a\u003e when you want a fully soluble calcium feed for fruiting crops without the sulphur. The two gypsum formats are compared at \u003ca href=\"\/pages\/liquid-gypsum-vs-granular-gypsum\"\u003eliquid gypsum vs granular gypsum\u003c\/a\u003e.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"drf-callout drf-callout-gold\"\u003e\n\u003cspan class=\"drf-callout-title\"\u003eStorage\u003c\/span\u003e\n\u003cp\u003eStore in a cool, dry place out of direct sunlight and above 5°C. Below that, sedimentation may occur; it is reversible on warming and shaking. Do not allow to freeze. Keep in the original container, not pre-diluted, and shake well before each use. Best used within 12 months of purchase. Keep away from children and pets.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\n\u003c!-- ═══════════ TAB 4 — FAQ ═══════════ --\u003e\n\u003cdiv class=\"drf-panel\" id=\"drf-lg-panel4\"\u003e\n\u003cspan class=\"drf-eyebrow\"\u003eQuestions \u0026amp; Answers\u003c\/span\u003e\n\u003ch2\u003eLiquid gypsum: the questions UK gardeners ask\u003c\/h2\u003e\n\u003cdiv class=\"drf-faq\"\u003e\n\u003cinput type=\"checkbox\" id=\"drf-lg-faq1\"\u003e\u003clabel class=\"drf-faq-q\" for=\"drf-lg-faq1\"\u003eWhat is liquid gypsum and what does it do?\u003c\/label\u003e\n\u003cdiv class=\"drf-faq-a\"\u003e\u003cdiv\u003eLiquid gypsum is natural calcium sulphate milled to a 5 micron average particle and held in suspension so it can be watered on. It feeds calcium and sulphur without changing soil pH, and on clay that disperses in water it holds the surface together so rain soaks in.\u003c\/div\u003e\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"drf-faq\"\u003e\n\u003cinput type=\"checkbox\" id=\"drf-lg-faq2\"\u003e\u003clabel class=\"drf-faq-q\" for=\"drf-lg-faq2\"\u003eWhy is it thick and creamy rather than a clear liquid?\u003c\/label\u003e\n\u003cdiv class=\"drf-faq-a\"\u003e\u003cdiv\u003eBecause it is a genuine mineral suspension. The micronised gypsum particles are physically present in the liquid, which is why it is opaque, dense and settles on standing. There is no synthetic dispersant holding the mineral up, so shake it before use. A liquid gypsum that never settles almost certainly contains one.\u003c\/div\u003e\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"drf-faq\"\u003e\n\u003cinput type=\"checkbox\" id=\"drf-lg-faq3\"\u003e\u003clabel class=\"drf-faq-q\" for=\"drf-lg-faq3\"\u003eIs liquid gypsum good for lawns?\u003c\/label\u003e\n\u003cdiv class=\"drf-faq-a\"\u003e\u003cdiv\u003eYes, particularly on clay. Calcium is a structural component of grass cell walls, sulphur supports protein synthesis and deepens colour, and because it is watered on it is one of the few ways to get calcium down to the clay under an established lawn. Maintenance is 10 ml per litre at 1 litre per square metre. Clay conditioning is 15 ml per litre at 1 litre per square metre, fortnightly for three months, started in early autumn where you can.\u003c\/div\u003e\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"drf-faq\"\u003e\n\u003cinput type=\"checkbox\" id=\"drf-lg-faq4\"\u003e\u003clabel class=\"drf-faq-q\" for=\"drf-lg-faq4\"\u003eDoes liquid gypsum work on clay soil?\u003c\/label\u003e\n\u003cdiv class=\"drf-faq-a\"\u003e\u003cdiv\u003eOn clay that disperses in water, yes: dissolving gypsum holds the salt concentration of the surface water above the point at which the clay plates come apart, so the surface stops sealing. On clay that does not disperse the effect is modest and organic matter does more. The dispersion test in the How to Use tab tells you which you have.\u003c\/div\u003e\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"drf-faq\"\u003e\n\u003cinput type=\"checkbox\" id=\"drf-lg-faq5\"\u003e\u003clabel class=\"drf-faq-q\" for=\"drf-lg-faq5\"\u003eWill liquid gypsum fix my waterlogged garden?\u003c\/label\u003e\n\u003cdiv class=\"drf-faq-a\"\u003e\u003cdiv\u003eOnly if the waterlogging comes from dispersive clay. It will not fix mechanical compaction, a high water table, an impermeable subsoil pan, missing land drains or poor site grading. If water sits on your soil because it has nowhere to drain to, no liquid product will change that. Run the four tests in the How to Use tab before buying.\u003c\/div\u003e\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"drf-faq\"\u003e\n\u003cinput type=\"checkbox\" id=\"drf-lg-faq6\"\u003e\u003clabel class=\"drf-faq-q\" for=\"drf-lg-faq6\"\u003eWhy use liquid gypsum rather than lime for calcium?\u003c\/label\u003e\n\u003cdiv class=\"drf-faq-a\"\u003e\u003cdiv\u003eLime raises soil pH; gypsum does not. Gypsum is a neutral salt with no liming value, so it adds calcium and sulphur to a soil that is already at the right pH without pushing it alkaline. If your soil is both acid and short of calcium, lime is the right product. If the pH is fine, gypsum is.\u003c\/div\u003e\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"drf-faq\"\u003e\n\u003cinput type=\"checkbox\" id=\"drf-lg-faq7\"\u003e\u003clabel class=\"drf-faq-q\" for=\"drf-lg-faq7\"\u003eMy soil calcium is fine, so why do I still get blossom end rot?\u003c\/label\u003e\n\u003cdiv class=\"drf-faq-a\"\u003e\u003cdiv\u003eBecause blossom end rot is a delivery problem rather than a supply problem. Calcium travels up in the transpiration stream and cannot be moved from old tissue to new, so hot weather, irregular watering or root damage starves the fastest-growing cells at the blossom end. Steady watering matters more than any calcium product. Gypsum is worth using where a soil test shows calcium is genuinely low.\u003c\/div\u003e\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"drf-faq\"\u003e\n\u003cinput type=\"checkbox\" id=\"drf-lg-faq8\"\u003e\u003clabel class=\"drf-faq-q\" for=\"drf-lg-faq8\"\u003eWhat is the difference between liquid gypsum and granulated gypsum?\u003c\/label\u003e\n\u003cdiv class=\"drf-faq-a\"\u003e\u003cdiv\u003eSame mineral, different job. Granulated gypsum is dug into beds and borders by the square metre and dissolves from the outside of each granule inwards. Liquid gypsum is milled to 5 microns, so it dissolves quickly and can be watered onto lawns, containers and established plants you cannot dig around. Use the granules where you can dig and the liquid where you cannot. See \u003ca href=\"\/products\/granulated-gypsum-clay-breaker\"\u003eGranulated Gypsum\u003c\/a\u003e.\u003c\/div\u003e\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"drf-faq\"\u003e\n\u003cinput type=\"checkbox\" id=\"drf-lg-faq9\"\u003e\u003clabel class=\"drf-faq-q\" for=\"drf-lg-faq9\"\u003eHow often do I need to reapply liquid gypsum?\u003c\/label\u003e\n\u003cdiv class=\"drf-faq-a\"\u003e\u003cdiv\u003eAbout every three years on heavy clay you are actively trying to improve, and the three-month lawn programme in the autumns you need it rather than every autumn on principle. Gypsum leaches out of wet soils, which is why it needs topping up, but an Ohio trial is clear on one thing: little and regular beats one heavy hit. A single heavy dose lowered maize yield in one of four years at both sites, and annual or two-yearly applications did better.\u003c\/div\u003e\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"drf-faq\"\u003e\n\u003cinput type=\"checkbox\" id=\"drf-lg-faq10\"\u003e\u003clabel class=\"drf-faq-q\" for=\"drf-lg-faq10\"\u003eIs liquid gypsum safe for pets and children, and is it organic?\u003c\/label\u003e\n\u003cdiv class=\"drf-faq-a\"\u003e\u003cdiv\u003eIt is mined calcium sulphate suspended in fulvic acid, with no synthetic dispersants. Treat it as you would any garden concentrate: store it out of reach, and keep pets and children off the area while you apply it. Once a drench has soaked in or a spray has dried, we know of no reason to keep them off. We do not describe it as organic and hold no third-party organic certification for it. We are not able to give a withholding period for edible crops. More at \u003ca href=\"\/pages\/is-liquid-gypsum-safe-for-pets\"\u003eis liquid gypsum safe for dogs, other pets and children?\u003c\/a\u003e\n\u003c\/div\u003e\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c!-- ===== END 4-TAB BODY ===== --\u003e\n","brand":"Dr Forest","offers":[{"title":"1 litre","offer_id":55997612917110,"sku":"DF-GYPSUM-1L","price":19.99,"currency_code":"GBP","in_stock":true},{"title":"500ml","offer_id":55997612949878,"sku":"DF-GYPSUM-500ML","price":12.99,"currency_code":"GBP","in_stock":true},{"title":"5 litre","offer_id":58813203841398,"sku":"DF-GYPSUM-5L","price":72.99,"currency_code":"GBP","in_stock":false},{"title":"2 x 5 litre","offer_id":58813203874166,"sku":"DF-GYPSUM-2X5L","price":135.0,"currency_code":"GBP","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0049\/8194\/8504\/files\/liquid-gypsum-micronised-calcium-sulphate-bottle.png?v=1786721043","url":"https:\/\/www.drforest.co.uk\/products\/liquid-gypsum","provider":"Dr Forest","version":"1.0","type":"link"}