Martins Natural Gypsum 20kg Clay Breaker & Soil Conditioner for Heavy Clay Soils

Martins Natural Gypsum 20kg: Clay Breaker and Soil Conditioner for Heavy Clay Soils

Martins Natural Gypsum is a 100% natural clay breaker and soil conditioner that improves the structure of heavy clay soils. It works by helping tightly packed clay particles group together into larger crumbs, which opens the soil up so water, air and roots can move through it. If your garden suffers from poor drainage, soggy patches or hard, compacted ground, gypsum is one of the simplest ways to start turning it around.

As well as improving structure, it supplies two plant nutrients: calcium (20.6%) and sulphur (15.3%). A real advantage of gypsum over lime is that it does this without changing the soil pH, so you can use it around almost any plant, including acid-loving types like azaleas and camellias, without pushing the soil more alkaline.

This is a Grade 1 natural gypsum, low in moisture and long-lasting in the soil. The 20kg bag suits larger garden beds, new lawns and ongoing clay improvement across a whole yard.

Key Features & Benefits

• 100% natural gypsum clay breaker and soil conditioner

• Improves the structure of heavy, compacted clay soils

• Increases water penetration and drainage, reducing soggy, waterlogged ground

• Improves aeration and encourages stronger, deeper root development

• Supplies calcium (20.6%) and sulphur (15.3%) as plant nutrients

• Does not change soil pH, so it's safe around most plants including acid-lovers

• Grade 1, low-moisture gypsum that lasts for years in the soil

Analysis

• Calcium (Ca): 20.6%

• Sulphur (S): 15.3%

• Grade 1 natural gypsum

How to Use

• Garden beds (moderate soils): work in up to 1kg per square metre

• Heavy clay soils: work in up to 2kg per square metre

• Dig or fork the gypsum evenly through the top 10 to 15cm of soil, ideally along with compost or organic matter

• For lawns or areas you can't dig, spread evenly over the surface and water in well

• When planting trees or shrubs, mix some gypsum through the soil at the base of the planting hole

• Water in after applying to help it start working

Getting the Best From It

• Do a quick jar test first: drop a small clump of your soil into a glass of clean water and wait 5 to 10 minutes. If the water turns cloudy and the soil disperses, gypsum will help. If the clump stays intact and the water stays clear, gypsum is less likely to work and adding organic matter is the better path

• Combine gypsum with compost and organic matter for the best long-term result, as together they improve structure faster than either alone

• Apply in autumn or winter where possible, so seasonal rain washes it through the soil

• Reapply yearly, or twice a year (spring and autumn) on very heavy clay, since clay improvement is a gradual process

• Keep up regular watering after application to keep the gypsum working through the profile

FAQs

What does Martins Natural Gypsum do?
It's a clay breaker and soil conditioner. It improves the structure of heavy clay soils so water, air and roots can move through more easily, which helps with drainage, compaction and root development, while also adding calcium and sulphur.

How much gypsum do I use per square metre?
Work in up to 1kg per square metre for moderate soils and up to 2kg per square metre for heavy clay. Dig it through the top 10 to 15cm, or for lawns spread it on the surface and water in.

Will gypsum change my soil pH like lime?
No. Unlike lime, gypsum improves clay without raising the pH, so it's safe to use around most plants, including acid-loving ones such as azaleas, camellias and blueberries.

Does gypsum work on all clay soils?
Not always. It works best on dispersive (sodic) clays. The simple jar-in-water test above tells you whether your soil will respond before you spread a whole bag.

How often should I apply it?
Generally once a year, or twice a year on very heavy clay. Improving clay is a gradual process, so regular applications combined with organic matter give the best results over time.

Where can I buy Martins Natural Gypsum in Australia?
Order online for delivery across Australia, or pick up in-store at Bonnyrigg, NSW. Delivery options for this 20kg bag are shown at checkout.