Essential Facts That Gardeners Should Learn About Vermiculate

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Hello! I am so glad that you found my blog. My name is Margaret, and I have always used gardening as a personal form of therapy. Over the years, I have started to look at the research behind this hobby of mine, and I have been so excited to read about the mood-boosting properties of microbes as well as about other topics. In this blog, I am going to write about grounding yourself with gardening. I plan to write about everything from aerating the ground to using gardening as a tool for meditation and personal reflection. Please, explore and share my posts if they inspire you. Thank you for reading!

Essential Facts That Gardeners Should Learn About Vermiculate

21 September 2021
, Blog

For plants to get valuable nutrients, you need to source the right potting soil. For example, adequate aeration and proper drainage are essential for healthy plant growth. One particular ingredient critical to gardening is vermiculite, a naturally occurring, odourless mineral in granular form. It is made from a mixture of silicon, aluminium, magnesium and iron. When mixed with gardening soil, vermiculite improves drainage and aeration. Although vermiculate can be expensive to buy, it ensures that plants grow healthy. Here are essential facts that gardeners need to know about vermiculate.

Benefits of Vermiculate 

Soil aeration is vital for the growth of strong roots to support a plant. However, compact soil inhibits root growth, causing plants to die. However, when vermiculite is mixed with garden soil, it breaks down the compactness, allowing proper aeration necessary for optimal plant growth. Through its reaction with other soil compounds, vermiculite also creates essential nutrients, such as magnesium, potassium and calcium, which are vital for healthy plants. Similarly, vermiculite improves soil drainage by soaking water akin to a sponge. Therefore, it is ideal for moisture retention in drier months. Furthermore, unlike compost that improves drainage but disintegrates over time into the soil, vermiculate offers long-term drainage improvement because it does not break down. Also, vermiculite is naturally sterile; hence, it cannot support pests and mould growth.

Granule Sizes 

Vermiculate for gardening is packaged into different grain grades and granule sizes to suit various potting tasks. Choose the small-grain option if you want to germinate seedlings because the grains support the growth of tiny roots. Conversely, coarse-grain vermiculate is suitable for improving soil profile and aerating in readiness for planting. However, regardless of size, vermiculite is not ideal for clay soil since it is already excellent at retaining water; thus, it can lead to waterlogging of soil. Talk to a soil and gardening expert to recommend the correct vermiculite granule size for your garden application and soil type.


Experts recommend that vermiculite be mixed with potting soil at a ratio of 25 percent vermiculite. However, the ratio may differ depending on the application and the soil type. Remember that some potting soils come pre-mixed with vermiculite. If potting soil is not pre-mixed, then you need to use your hands to mix the two ingredients consistently for even integration. For improved seed germination, vermiculate can be used alone. However, it requires the addition of small quantities of water.