{"title":"Lime \u0026 pH Buffers","description":"\u003cp\u003eIn a living soil most of what looks like a deficiency is a lockout: the nutrient is present but the pH has drifted far enough that roots cannot reach it. These are the inputs you reach for to correct that, and the choice between them comes down to what you want to happen to pH.\u003c\/p\u003e\n\u003cp\u003eOyster shell lime is a slow carbonate that nudges pH up and carries trace minerals with it. Wollastonite raises pH while adding plant-available silica alongside calcium. Magnesium carbonate buffers pH upward and supplies magnesium without adding calcium, which is useful when you are tuning a calcium-to-magnesium ratio. Gypsum is the exception in this range — it supplies calcium and sulphur and leaves pH alone, so it suits mixes that are already where you want them, or coco-based mixes you do not want to push higher.\u003c\/p\u003e\n\u003cp\u003eTest before you dose. All four are slow to act, and correcting pH by guesswork is how a small problem becomes a locked-up one.\u003c\/p\u003e","products":[{"product_id":"oyster-shell-lime","title":"Oyster Shell Lime","description":"\u003cp\u003eOyster Shell Lime is a premium soil amendment derived from 100% locally farmed and sourced oyster shells — but this isn't simply crushed shells. This product is the result of a decade of development and refinement, built around solving the biggest problem with conventional oyster shell powder: sodium. Most oyster shell products on the market haven't had anything done to mitigate the sodium naturally present in any sea-based ingredient, meaning you're adding calcium but bringing sodium along with it — and plants unfortunately uptake sodium with greater ease than calcium, leading to lacklustre results.\u003c\/p\u003e\n\u003cp\u003eOur custom process begins with desalinating, cleaning, and pasteurising the shells, which are then fully dried and processed through multiple grinding and sieving stations to yield a uniform, clean, garden-worthy end product. Available in powder form, it provides a slow-release source of calcium and trace minerals — notably zinc — along with conchiolin, a protein that appears to enhance calcium uptake. The result is improved soil structure and drainage, boosted beneficial microbe populations, and reliable calcium supply without the sodium baggage.\u003c\/p\u003e","brand":"Soil Supply Co.","offers":[{"title":"500g","offer_id":48918020620528,"sku":"OYSTERSL-500G","price":12.0,"currency_code":"AUD","in_stock":true},{"title":"1kg","offer_id":48918020686064,"sku":"OYSTERSL-1KG","price":24.0,"currency_code":"AUD","in_stock":true},{"title":"2.5kg","offer_id":48918020751600,"sku":"OYSTERSL-2.5KG","price":55.0,"currency_code":"AUD","in_stock":true},{"title":"5kg","offer_id":48918020817136,"sku":"OYSTERSL-5KG","price":95.0,"currency_code":"AUD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0823\/1262\/6416\/files\/oystershelllime_47dbb927-8d2c-4b33-9243-e16032c040ad.png?v=1783649127"},{"product_id":"wollastonite","title":"Wollastonite","description":"\u003cp\u003eWollastonite (Calcium Silicate) is a dual-purpose mineral amendment providing both calcium and silica in a single ingredient — two minerals plants need in good supply throughout the growing season to form thick, resilient leaves and strong stems.\u003c\/p\u003e\n\u003cp\u003eUsing wollastonite as part or all of your liming ingredient lets you adjust pH while simultaneously building plant-available silica levels in the soil. The results speak for themselves — plants grown with wollastonite show improved resistance to pests, disease, and even drought, alongside higher yields and better overall quality. It pairs well with oyster lime and gypsum, creating overlapping calcium sources while getting more silica into the soil than any of those ingredients can provide alone.\u003c\/p\u003e","brand":"Soil Supply Co.","offers":[{"title":"500g","offer_id":48918021800176,"sku":"WOLLA-500G","price":6.5,"currency_code":"AUD","in_stock":true},{"title":"1kg","offer_id":48918021832944,"sku":"WOLLA-1KG","price":10.0,"currency_code":"AUD","in_stock":true},{"title":"2.5kg","offer_id":48918021865712,"sku":"WOLLA-2.5KG","price":20.0,"currency_code":"AUD","in_stock":true},{"title":"5kg","offer_id":48918021898480,"sku":"WOLLA-5KG","price":38.0,"currency_code":"AUD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0823\/1262\/6416\/files\/wollastonite.png?v=1782530068"},{"product_id":"magnesium-carbonate","title":"Magnesium Carbonate","description":"\u003cp\u003eMagnesium Carbonate (Magnesite) is a slow-release, non-sulphate source of magnesium that doubles as a soil pH buffer — raising pH in much the same way as lime or oyster shell powder, but supplying magnesium instead of calcium. If you've used dolomite, you've used something similar — dolomite is calcium magnesium carbonate, while this is purely magnesium and carbon without calcium tagging along. That distinction lets you fine-tune your calcium-to-magnesium ratios with real precision, rather than being forced to add both every time you adjust pH.\u003c\/p\u003e\n\u003cp\u003eMagnesium is critical to enzymatic processes throughout the plant's life cycle, and running short of it will affect overall performance drastically — particularly flower quality and yield. Because magnesium carbonate is insoluble and non-acidic, it fills a completely different role to ingredients like kieserite or soluble magnesium sulphate, providing a long-term background supply rather than a quick soluble hit.\u003c\/p\u003e","brand":"Soil Supply Co.","offers":[{"title":"500g","offer_id":48918021931248,"sku":"MAGCARB-500G","price":12.0,"currency_code":"AUD","in_stock":false},{"title":"1kg","offer_id":48918021964016,"sku":"MAGCARB-1KG","price":20.0,"currency_code":"AUD","in_stock":false},{"title":"2.5kg","offer_id":48918021996784,"sku":"MAGCARB-2.5KG","price":40.0,"currency_code":"AUD","in_stock":false},{"title":"5kg","offer_id":48918022029552,"sku":"MAGCARB-5KG","price":70.0,"currency_code":"AUD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0823\/1262\/6416\/files\/magcarb.png?v=1782530257"},{"product_id":"gypsum","title":"Gypsum","description":"\u003cp\u003eGypsum (Calcium Sulphate) is a high-purity, pH-neutral source of calcium and sulphur — essential for situations where you need to top up calcium without shifting your soil's pH. If anything, it carries a very mild acidifying quality, making it a smart choice for mid-season amendments, coco-based mixes, or any blend that isn't inherently acidic and doesn't need further alkalinity.\u003c\/p\u003e\n\u003cp\u003eProviding approximately 20% calcium and 16% sulphur, gypsum supports strong cell wall development and enzyme function across all growth stages. It's particularly well suited to acidic-soil-loving plants that still need adequate calcium supply — a combination that's hard to achieve with liming agents.\u003c\/p\u003e\n\u003cp\u003eWe stock white, graded gypsum with an approximate maximum particle size of 2–3 mm, with the majority being fine powder. Not all gypsum is equal — cheap sources are often recycled from gyprock particle board or pulled from low-quality mines where seam wall material ends up mixed with the extract. Both are inferior due to potential contamination and reduced purity.\u003c\/p\u003e","brand":"Soil Supply Co.","offers":[{"title":"500g","offer_id":48918022619376,"sku":"GYPSUM-500G","price":6.5,"currency_code":"AUD","in_stock":false},{"title":"1kg","offer_id":48918022652144,"sku":"GYPSUM-1KG","price":10.0,"currency_code":"AUD","in_stock":false},{"title":"2.5kg","offer_id":48918022684912,"sku":"GYPSUM-2.5KG","price":22.0,"currency_code":"AUD","in_stock":false},{"title":"5kg","offer_id":48918022717680,"sku":"GYPSUM-5KG","price":38.0,"currency_code":"AUD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0823\/1262\/6416\/files\/gypsum.png?v=1782530376"}],"url":"https:\/\/soilsupply.co\/collections\/lime-ph-buffers.oembed","provider":"Soil Supply Co.","version":"1.0","type":"link"}