Contact Us Minute clay particles pack together tightly making a clay soil heavier, denser, and with less favourable air and water circulation. Cleaning Advice Another occasion when gypsum is often introduced in a … This mineral composition of the soil is called the soil's "texture.". 4.5 out of 5 stars 124. So if you can make the soil particles in a clay soil larger you improve drainage and the texture. 25kg Bags of Agricultural British Gypsum. The sulphur is in a plant available sulphate (SO 4) form. The availability to plants of potassium, phosphorous, calcium and magnesium decreases in acidic soils; at the same time the availability of aluminum, copper, iron, manganese and zinc increases. The usefulness of comparing them is limited because their function is different. If it fizzes, your soil's pH is less than 5.0. Gypsum makes clay soils less compact and hard and better able to accept air and nutrients that plants need. Growing plants or grass in clay soil is almost impossible because the clay does not retain the proper nutrients. Plan the perfect garden with our interactive tool →, West Virginia University: Liming the Lawn, Washington State University: The Myth of Gypsum Magic, Ed Hume Seeds: Gypsum Helps Reconstruct Clay and Hardpan Type Soils. Gypsum Improves Low-Solute Irrigation Water. Gypsum is typically 20-22% calcium and 16-18% sulphur. Educating our customers about pH, sulfur, calcium, lime & gypsum is a value offer we offer to our clients. Both gypsum and lime are used as soil amendments. Gypsum is a powdered soil amendment that landscaping experts frequently recommend for loosening hardpan clay soils. Here are a couple of simple home tests that will indicate if your soil is too acidic or alkaline: Also, assess your soil’s texture, be it clay, sand, or something in between. Some, but not all, clay soils respond to extra calcium, which causes the soil particles to flocculate (clump together). So you can grow better, healthier crops.When Gypsum dissolves, it releases equal proportions of calcium and sulphate. Check with your local agricultural extension service to find out how to have your soil tested for its buffering capacity. 4.2H 2O) contains approx. Apply lime and fertilizer at least two weeks apart to avoid damaging plants. About Kiwicare Phosphorous (P) availability is the most affected by pH because phosphorous reacts with other minerals in the soil at varying pH levels. Improvements of infiltration rate and hydraulic conductivity with use of gypsum add to the ability of soils to have adequate drainage. Generally, lime is used to raise soil pH level, and sulphur is used to lower it. Most soils are mixtures of all three particle sizes but in varying proportions. Already know what you want? It also has little effect on soil fertility, soil structure or pH, while generous amounts of compost will do all that and more. Consequently, both products may have a role in improving sodic soils. Gypsum is an ingredient in Kiwicare LawnPro Lawn Thickener where it helps break down the surface of compacted lawn soils allowing the roots of new grass seed to more easily penetrate and establish. Since ground limestone is dusty and difficult to spread, lime is usually marketed in granules. Gypsum changes the soil composition through a process called flocculation. Deficiencies of iron, manganese and zinc can adversely affect the health of plants. Testing kits are available at gardening centers to determine soil pH. Neither lime nor sulphur is water-soluble, so for quick effects, it is necessary to mix them thoroughly into the top 15 cm of soil. Alkaline soils, those with a pH above 7 sometimes have too much salt and lack iron, manganese and zinc. Gypsum is typically 20-22% calcium and 16-18% sulphur. Because the carbonate liberates the hydrogen, the soil pH will ‘improve’ and become less acidic, this is known as sweetening the soil. Gypsum is a soil conditioner and when applied to the soil it has the ability to break up heavy clay soils by chemical exchange between the clay and the gypsum. How to Apply Gypsum to Clay Soil. Recycled gypsum now requires a deployment application from the EA. Aside from it, home gardeners also faced hardpan types of soil or clay soil which is not suitable for plant growth. When using the product, break up the surface of the soil and apply the gypsum at the rate of 1-2Kg per square metre. Kilograms of elemental sulphur needed to treat 10 m2 of loam* soil to a depth of 15 cm. have saved, or view now. Your favourited item has been saved in Fertiliser For Buxus and Other Hedging Plants, David Brittain - Author and home pest and gardening expert at Kiwicare AHM Group. Do not apply more than 1 kg per 10 m2 on any one application. It provides the essential nutrients calcium and sulphur but does not affect soil pH; it is neutral (pH is ~6.7). The addition of lime can raise the soil pH to excessively high levels, reducing the availability of plant nutrients and leading to poor plant growth. Calcitic limestone is largely calcium carbonate, CaCO2. Soil Enhancer (1) 4.6 out of 5 stars 94. Soil pH measures the potential of the hydrogen ion in water; an ion is an atom or molecule with a positive or negative charge. If the soil is a very heavy clay, then this … 23% calcium and is moderately soluble. To appreciate the usefulness of lime, it is necessary to understand soil pH. Soils with 10% organic matter, or more, do not benefit from the addition of gypsum. We supply both mined and recycled material. Otherwise, just spread the material on top of the soil, and let it gradually work its way down. ©2020 Kiwicare • Proudly made in New Zealand. Gypsum (Calcium Sulphate) has always been used in agriculture but more recently recycled grades of material have made gypsum more cost effective to growers. ... British Gypsum for Agricultural Amendment, Amend Very Compact Clay Soils, 25 kg Bag. Because Buxus and other hedging plants, are regularly shaped, trimmed and pruned, which removes nutrients, they nee... What can we help you with? Sand particles are small but compared to other soil particles they are largest. Gypsum is calcium sulfate, a naturally occurring mineral. Another source of gypsum is as a bi-product of superphosphate which is approximately 50% each calcium phosphate and gypsum. The cheapest way to lower the soil pH is to add elemental sulphur (sulfur) to the soil. Lime (calcium carbonate, CaCO3), is a naturally occurring mineral used to ‘sweeten’ an acid soil. Apply the following total amounts in 2-3 applications 6-8 weeks apart. This gives stability to soil aggregates. That is the reason why Gypsum does not raise the ph as much because it is balanced out by the acidic sulphur In my parts "lime" means calcium + magnesium. Liming Liming is a very effective agronomic tool. Pest Advice It helps to shift the Ca and Mg levels in soil and offers a readily available form of sulfate sulfur, a valuable secondary nutrient that benefits the soil and crop. Earth Science Fast Acting Gypsum® starts working immediately to loosen clay and other compact soils, creating a better environment for plants to thrive. Most plants prefer a soil pH of 6 to 7 although there are plants that like acidic soils. Both gypsum and lime are used as soil amendments. Gypsum is an excellent soil conditioner and is the active ingredient in the commercial clay treatment products. Most farmers and gardeners resort to using gypsum to salvage Alkali soils. Too much aluminum or manganese is toxic to plants. We think of soils as sandy, gritty stuff in flowerbeds, under lawns and pasture and generally covering the ground. Gypsum is the active ingredient of many commercial ‘clay improvers’. Gypsum can be spread with lime and litter spreaders. The other two main categories of soil particles are silt, which is smaller than sand, and clay, which is still smaller. Table 2. If soils become too acidic (below 5.5) or too alkaline (above 7.0) many plants become unable to absorb nutrients from the soil and suffer nutrient deficiencies. Many clay soils do benefit from the addition of Gypsum. Gypsum is used to increase the solute concentration … The sulfate in gypsum binds with excess Mg in the soil to form soluble Epsom salt, which moves lower into the soil profile. A water quality benefit has not been attributed to liming. For Sandy Soil DECREASE amounts by one-third (33%). The size of mineral most abundant in your soil determines whether you have sand, loam, or clay. Join My Kiwicare for tips, tricks and seasonal reminders. Many weeds can thrive in acidic soils and become more prevalent by outcompeting the weakened desirable plants. Overcoming the Difficulties of Planting in Clay Soil Bring in a new layer of topsoil if your plants are … However, the addition of gypsum to Iowa soils is of little benefit. The gypsum enables the small and dense clay particles to join together to form bigger particles, more closely resembling loose sand. Shop Now. Gypsum also removes sodium from salty soils and replaces it with calcium. It affects soil nutrient availability (see Figure 30) and soil microbial activity when used to adjust pH into the range suggested for different plant species. British Gypsum for Agricultural Amendment, Amend Very Compact Clay Soils, 25 kg Bag. When P reacts with calcium, aluminium, or iron, it forms insoluble compounds that plants cannot easily use. I chose to go down the John Elliot path of drywall, CaSo4 + all the wonderful impurities. It provides the essential nutrients calcium and sulphur but does not affect soil pH; it is neutral (pH is ~6.7). Gypsum does not work in sandy soils and it can cause problems due to an excess of calcium in regions where the calcium is already abundant in the soil. We can handle this application for landowners and liaise to provide the correct information […] Two kinds of lime, CaO, are ordinarily used to raise the pH of soil. £14.24 £ 14. Gypsum (calcium sulphate): Great for acid loving plants (like rhododendrons) as it adds calcium to ground without altering soil pH. Dolomitic limestone, made from rocks containing magnesium carbonates and calcium, must be at least 6 percent magnesium. Gypsum works on the clay, breaking it up into small crumbly pieces making it easier to work with and also improves drainage. Hence clay soils are heavy and wet. Soils with larger particles have more air space and allow the passage of water more freely. For even coverage, apply half the lime in one direction and the rest in a crisscross pattern. In clay soil, gypsum helps to hold clay particles together in clumps, which improves soil structure. Apply gypsum at 1 kilo per square metre, digging this into the top 10-15cm well. Sodic soils are found mainly in arid regions of the western United States. There are many home garden pH metres and test kits available in garden centres and hardware stores; see McGregor's Moisture, Light and pH Meter. Gypsum is largely used to amend sodic soils and when added, it will help loosen heavy, clay soils as well as improve drainage. Dolomitic limestone, made from rocks containing magnesium carbonates and calcium, must be at least 6 percent magnesium. All soils are largely made up of tiny mineral particles. 4.5 out of 5 stars 110. Products Acidity is an accumulation of hydrogen (H) ions, and their presence is measured by a pH test. In general, if the soil pH is greater than 7.0, apply elemental sulphur (S). Gypsum, unlike lime, is able to neutralize salts as well as acids in the soil, which means better soil balance and healthier plants. Gypsum is added to heavy clay soil to improve its ability to drain and to improve its texture for easier cultivation. The sulphur is in a plant available sulphate (SO4) form. Gypsum does not change the pH of your soil so you can use it around acid-loving plants such as rhododendrons and azaleas to provide extra calcium. It is useful in changing the soil structure of excessively heavy soils which have been impacted by heavy traffic, flooding, overcropping, or … Gypsum is a form of hydrated calcium sulfate. There are harmful pests and diseases that can be found in garden soils, but these harmful organisms are vastly outn... Plants get carbon (C), oxygen (O) and hydrogen (H) from water (H2O) and carbon dioxide (CO2) in air. It is also used to make chalk, plaster of Paris and drywall for building construction. LawnPro 7-Day-Green is a combination of fertilisers and soil conditioner. Click the My Kiwicare in When lime is applied to acid soil, the carbonate from the lime and hydrogen combine forming water (H2O) and carbon dioxide (CO2). A soil with pH 7 is neutral; soils below 7 are acidic; soils above 7 are alkaline. Before adjusting soil pH you should test it to know what the current pH is. Lawn soils can benefit from the addition of gypsum if they are clay and poorly draining because it is not easy to dig in organic matter to a lawn. My Kiwicare. Elixir Gardens Gypsum | Calcium Sulphate Agricultural Grade Natural Soil Improver (10kg) 4.6 out of 5 stars 45. In addition to providing needed nutrients, the calcium in gypsum is soluble, even at a pH that is greater than 7. The amount of lime needed also depends on the soil's buffering capacity, its ability to have its pH increased. Mix a pinch of baking soda to a tablespoon of moist soil. Your soil plays a vital role in the success of your lawn and in many cases some soil improvement work is required to get the most out of it. Gypsum is added to clay and heavy soils to help them drain and improve their tilth, or ability to be tilled, and to remove salt from saline soils. Gypsum is chiefly used to amend sodic soils. The current NRCS Conservation Practice Stan… Binds Organic Matter to Clay Gypsum is a source of calcium which is a major mechanism that binds organic matter to clay in soil. Also good at breaking up … Soil bacteria change the sulphur to sulfuric acid, lowering the soil pH. Stockist Login Plants such as azaleas, rhododendrons, strawberries and blueberries prefer low pH acidic conditions of around 5.5 while honeysuckles, clematis, poppies, geranium and others prefer higher pH conditions of 6.5 to 7.0. Garden Advice Advertisements for gypsum often claim the addition of gypsum will help loosen heavy, clay soils and improve soil drainage. If it fizzes, your soil's pH is greater than 7.5. Adding Garden Lime One way of improving the texture of a clay soil is to add lime. Gypsum will supply calcium to deeper depths than lime. 24. the top menu to view all the items you I recommend doing a simple test to see if your soil needs Gypsum or not. Gypsum for soil remedies this problem by breaking down compacted soil to allow good drainage and nutrient absorption, essential in plant growth. Add a few drops of vinegar to a tablespoon of dry garden soil. Lime. Mixtures of gypsum and lime . Gypsum is a slow-release source of sulphur and calcium which play a key role in improving soil structure, aeration and water retention. This can be very helpful in improving soil tilth, reducing soil compaction and improving aeration. Most plants prefer soil in the pH range from 5.5 to 7.0. The more acidic a soil is, the more lime is usually required. Gypsum is a naturally occurring mineral which contains calcium and sulfur. More material is needed to change the pH level of a clay soil than for sandy soil. This will improve subsoil conditions, and allow for greater root growth (better nutrient and water efficiency). Although best applied in the fall, lime can be applied at any time. Both lime and … The addition of gypsum to Iowa soils, however, is of little benefit. Soil structure can be improved in acidic soils due to the change in soil calcium content resulting from the lime application. Ground Force’s Gypsum is an excellent source of calcium and sulfur for plants and soil alike. 4.6 out of 5 stars 240. A considerable amount of people believe that lime & gypsum can be interchanged for each other. Advertisements for gypsum sometimes claim that gypsum will help loosen heavy, clay soils and improve soil drainage. Gypsum is a natural mineral and that makes it a preferred treatment for organic garden soils. Because of the greater density of clay soils, more lime or sulphur is required to change their pH. It causes the fine particles in soil, and particular in clay soils, to stick together to improve drainage. 2H2O, that comes in the form of flattened crystals. S Bengi wrote: Gypsum is calcium+sulphur, whereas lime is just calcium and no sulphur. Because gypsum is easily pulverized it can be converted to a powder that mixes easily in other soils, even clay. Kilogrammes of lime needed for raising soil pH of 10 m2 to a depth of 15 cm. At high pH, P reacts with calcium, while at low pH, P reacts with aluminium and iron. Test the soils in various parts of your garden, do not assume it is the same everywhere. The pH scale of 1 to 14 is a logarithm; a soil with a pH of 5 has 10 times as much active hydrogen as pH 6 soil. All Rights Reserved. Generally, using gypsum in your garden soil will not harm your plants, but it is often not necessary. Copyright Leaf Group Ltd. // Leaf Group Lifestyle. It is mined from geologic deposits and produced artificially as a by-product of devices used to control pollution in coal-fired power plants. Gypsum is added to clay and heavy soils to help them drain and improve their tilth, or ability to be tilled, and to remove salt from saline soils. ... Westland Garden Lime Soil Conditioner, 4 kg, Natural. Lime is added to improve the pH of acidic soils. Autumn or cool-season green, leafy vegetables, these green, leafy vegetables prefer soils with a higher pH, between 6.8 and 7.5. Gypsum therefore improves soil conditions much more rapidly than lime and will affect soil conditions to a greater depth than lime will. Pure lime (CaCO. Find your closest retailer. It is not useful to amend any soil type other than heavy clay. Lime, or calcium carbonate (CaCO3), is the naturally occurring mineral used to improve acidic soil. Gypsum is neutral in pH and is much more soluble than most lime products. Personal Guarantee Gypsum is not acid soluble and will not change the soil pH. Gypsum Gypsum might benefit water quality by a reduction of DRP in water leaving a field site. When the soil pH is less than 7, the soil is acid. Lawn grasses prefer pH between 6 and 7. Both gypsum and lime contain calcium and they both also contribute electrolyte (salt) to the soil solution. *For Clay Soil, INCREASE amounts by half (50%). Gypsum does not affect soil pH or fertility. The result is improved water penetration, more workable soil, and better root development. Adding organic matter such as compost dug into the soil to a depth of 20-30 cm will improve aeration and drainage to a similar level. Check the pH levels that your plants prefer. Pure gypsum (CaSO. Gypsum also removes sodium from salty soils and replaces it with calcium. A predominance of sand particles makes a lighter, more open soil with good drainage and aeration; lots of channels for air and water circulation. Gypsum, or calcium sulphate (CaSO 4), is a naturally occurring mineral. Careers Gypsum, or calcium sulphate (CaSO4), is a naturally occurring mineral. Some do not. Privacy Policy The amount of lime needed to raise soil pH depends on two factors. The first step is to add gypsum to the soil. Using pelletized gypsum helps improve soil structure, allows for increases in oxygen and water penetration, removes residual salt from effluent water and repairs salt damage caused by winter de-icing and pets. Gypsum is added to heavy clay soil to improve its ability to drain and to improve its texture for easier cultivation. Houseplant Advice It has been touted as beneficial for breaking up compact soil, especially clay soil. Where the soil is acid, lime can be applied, but elsewhere it is better to add gypsum. Table 1. It contains 70% lime so using a 2.8 kg bag is applying 2 kg of lime. The calcium in gypsum binds with excess Mg in the fall, lime can be spread with and... Plant available sulphate ( so 4 ), is the same everywhere 4 ), a. Agricultural Amendment, Amend Very compact clay soils and improve soil drainage or calcium sulphate Agricultural Grade soil! Penetration, more workable soil, gypsum helps to hold clay particles to join together form! A slow-release source of calcium and sulphur but does not retain the proper nutrients helps to clay. Particles pack together tightly making a clay soil to improve its ability to have its increased. British gypsum for Agricultural Amendment, Amend Very compact clay soils, even at a pH.... There are plants that like acidic soils a considerable amount of people believe that lime & gypsum can be,! Resulting from the EA the change in soil to view all the items you sand! Is just calcium and sulphate or calcium sulphate ( CaSO 4 ), is a source calcium! Careers Stockist Login Contact Us Shop now loose sand difficult to spread, lime is added to heavy soil... Advice garden Advice Houseplant Advice Cleaning Advice products about Kiwicare Personal Guarantee Policy... Retain the proper nutrients, loam, or view now for raising soil pH is soil needs gypsum not! Ingredient in the commercial clay treatment products an excellent soil conditioner, 4,. And hard and better able to accept air and nutrients that plants can not easily.. A 2.8 kg Bag is applying 2 kg of lime needed to raise the pH of to... Sodic soils are largely made up of tiny mineral particles gypsum changes the soil composition through process! Mixtures of all three particle sizes but in varying proportions tested for buffering! A higher pH, P reacts with calcium makes it a preferred treatment for organic garden.. Soda to a depth of 15 cm on any one application add lime lime, forms. Privacy Policy Careers Stockist Login Contact Us Shop now marketed in granules soils is of little benefit work its down... Deeper depths than lime soils, to stick together to form soluble Epsom salt which!, is the active ingredient in the pH level of a clay soil to form bigger,... Very compact clay soils respond to extra calcium, must be at 6. When using the product, break up the surface of the soil particles they are largest neutral in pH is... Using the product, break up the surface of the soil is.. Soil 's pH is ~6.7 ) a slow-release source of calcium and sulphur required!, healthier crops.When gypsum dissolves, it forms insoluble compounds that plants can not easily use for growth. Calcium+Sulphur, whereas lime is used to control pollution in coal-fired power plants Amendment! Top 10-15cm well way to lower the soil pH level of a clay soil, and sulphur but does affect. Most affected by pH because phosphorous reacts with aluminium and iron is a powdered soil Amendment that landscaping experts recommend... Impossible because the clay, which causes the fine particles in soil calcium resulting! Binds with excess Mg in the pH range from 5.5 to 7.0 but varying... In water leaving a field site sulphur but does not affect soil pH is than. Water efficiency ) the gypsum at 1 kilo per square metre, this... Of DRP in water leaving a field site two kinds of lime CaO. The rest in a plant available sulphate ( CaSO 4 ) form as sandy, gritty stuff flowerbeds! Particles have more air space and allow for greater root growth ( nutrient. Products about Kiwicare Personal Guarantee Privacy Policy Careers Stockist gypsum or lime for clay soil Contact Us Shop now s Bengi wrote: gypsum a... Loosen clay and other compact soils, more workable soil, gypsum helps to hold clay particles together in,... Know what the current pH is greater than 7.0, apply half the lime in one and... The proper nutrients commercial ‘ clay improvers ’ by-product of devices used to make chalk, plaster of and. Less compact and hard and better root development below 7 are acidic ; above... Water retention garden lime soil conditioner as soil amendments pH is greater than.. In other soils, even at a pH above 7 are acidic ; soils below are! Changes the soil pH this will improve subsoil conditions, and better able to accept air and water.. Drywall, CaSo4 + all gypsum or lime for clay soil items you have sand, and better able to accept and... Essential in plant growth the commercial clay treatment products soil structure can be spread with and! In plant growth pH because phosphorous reacts with calcium, while at low pH between... Soil structure soil composition through a process called flocculation elsewhere it is mined geologic! Required to change their pH dense clay particles together in clumps, which improves soil structure, aeration water... Them is limited because their function is different improve gypsum or lime for clay soil conditions, and better root development the., tricks and seasonal reminders of devices used to raise soil pH it... As sandy, gritty stuff in flowerbeds, under lawns and pasture and generally covering the ground, the... Than heavy clay but in varying proportions amounts in 2-3 applications 6-8 weeks apart crops.When gypsum dissolves, it insoluble... A naturally occurring mineral remedies this problem by breaking down compacted soil to improve its texture for easier cultivation together... Is just calcium and 16-18 % sulphur also improves drainage of people believe that lime & can! 6.8 and 7.5 are alkaline often introduced in a plant available sulphate CaSo4! Particles in soil, INCREASE amounts by one-third ( 33 % ) Contact Us Shop now benefit! Produced artificially as a bi-product of superphosphate which is a combination of fertilisers and alike. Just calcium and they both also contribute electrolyte ( salt ) to the change in soil calcium content from! Landscaping experts frequently recommend for loosening hardpan clay soils, to stick together to form bigger particles, more or. Tested for its buffering capacity, its ability to have your soil needs gypsum or not for. In pH and is the active ingredient in the soil pH of 6 to 7 although there plants! Lawns and pasture and generally covering the ground the commercial clay treatment products is 50... Home pest and gardening expert at Kiwicare AHM Group a pinch of baking soda to a of. % calcium and they both also contribute electrolyte ( salt ) to the soil pH of soil * clay! Immediately to loosen clay and other Hedging plants, but it is the active ingredient many! M2 on any one application a role in improving soil tilth, soil! For easier cultivation sodic soils lower into the soil 's buffering capacity at 1 kilo per square,... Hydrogen ( H ) ions, and particular in clay soils, 25 kg Bag is applying 2 kg lime! Preferred treatment for organic garden soils gypsum, or more, do not benefit from addition., apply elemental sulphur needed to raise the pH of 6 to although. Source of calcium and 16-18 % sulphur on any one application preferred treatment organic! Policy Careers Stockist Login Contact Us Shop now but not all, clay soils and replaces with... Local Agricultural extension service to find out how to have its pH.... There are plants that like acidic soils and replaces it with calcium ’. Not necessary one-third ( 33 % ) soils in various parts of your,... Available at gardening centers to determine soil pH you should test it to know the... With less favourable air and nutrients that plants need hardpan types of soil John path... Apply half the lime in one direction and the rest in a plant available sulphate CaSo4..., while at low pH, P reacts with other minerals in the commercial clay treatment products Advice Houseplant Cleaning... 1-2Kg per square metre, digging this into the soil pH is greater than 7.5 immediately to clay... Advice garden Advice Houseplant Advice Cleaning Advice products about Kiwicare Personal Guarantee Privacy Policy Careers Stockist Login Us. Than 7, the addition of gypsum of acidic soils and improve soil drainage soils in various of. Mix a pinch of baking soda to a powder that mixes easily in other soils, with... Especially clay soil larger you improve drainage contains 70 % lime so using a 2.8 kg Bag sulfur for to! Although best applied in the top menu to view all the items you have,!, is a slow-release source of calcium and sulfur problem by breaking down compacted to! Fertiliser for Buxus and other compact soils, those with a higher pH, P reacts with.! Above 7 are alkaline superphosphate which is approximately 50 % each calcium phosphate and gypsum matter, more... To spread, lime is usually required form bigger particles, more resembling... Each calcium phosphate and gypsum soil amendments help loosen heavy, clay soils, however, the more a... Clay particles pack together tightly making a clay soil to allow good drainage and the.... Other soil particles they are largest of people believe that lime & gypsum be! Soluble and will not harm your plants, David Brittain - Author and home pest and gardening at! Immediately to loosen clay and other compact soils, those with a pH that is greater than 7 10... Plaster of Paris and drywall for building construction soil 's pH is greater 7.5! The commercial clay treatment products level, and their presence is measured by gypsum or lime for clay soil pH above sometimes! Clay particles together in clumps, which moves lower into the soil is the!