You know your garden soil needs some amendments, but you’re split between using vermiculite and perlite. Many garden owners suffer from this dilemma too, as there is a lot of confusion about what they are, their differences, uses, and other things.
Vermiculite and perlite are natural soil additives that can improve the structure of your soil, whether you’re making potting soil for your container gardening or you want to affect the change directly on the ground. Even though these additives are pretty valuable, they can cause problems if you don’t make the right choice. Although they serve the same purpose, they are not interchangeable. They have different compositions, suitability, and more.
To make it easier for you and ensure you do not make the wrong decision and use an addictive that can damage your plants, we’ve put together this guide showing what these two natural soil additives are and how they differ from each other.
What is Vermiculite?
Vermiculite is a common name for hydrated laminar magnesium-aluminum-iron silicate. Vermiculite is a natural mineral gotten from the ground through mining before being processed into a flaky golden brown to dark brown hue. It has a neutral pH of 7.0 but slightly increases the pH of your plants.
When added to the soil, Vermiculite helps to increase water and nutrient retention. It is a permanent solution and does not decompose like compost. Instead, it swells and forms a worm-like tissue when activated with water.
Vermiculite can be added to potting mixes, directly to the soil, and even in fertilizers and pesticides to prevent caking since it can retain moisture. You can choose large, medium, or fine particles sizes.
How Does Vermiculite Work?
Vermiculite helps the soil retain both moisture and nutrients by trapping them in its molecules and slowly releasing them overtime for the plants to use. When vermiculite is mixed with soil, and activated with water, it helps to aerate the soil. It swells and takes water, nutrients into its molecules while slowly releasing them to the plants.
Benefits of Using Vermiculite
- Vermiculite improves the water and nutrient retention in the soil
- It is sterile
- It improves root growth
- It has a neutral pH
- Improves soil quality
- Promotes rapid growth
- Prevents mold and mildew
What is Perlite?
Perlite is another natural soil additive obtained from heating obsidian, a volcanic glass. When obsidian comes in contact with water, a unique volcanic glass with high water content is formed. This material is also known as perlite. It creates a highly porous, amorphous, hard material with a pH slightly greater than 7.0. It is rich in silicone.
Perlite has a white hue, and its particles are generally smaller than vermiculite. You can choose between the medium and fine particles as they are the most common. Perlite is lightweight, has no odor, and is clean.
Perlite will crumble into powder when put under pressure. Perlite helps to aerate the soil, improve drainage and introduce oxygen to the plant’s root.
How Does Perlite Work?
Perlite can be spread on the ground or in a potting mix. You can also mix the perlite in a 50:50 ratio into the compost of seeds and cuttings. You can pour the finer perlite particles on the seeds as it’ll allow light to pass and aid germination.
Benefits of Using Perlite
Here are some reasons people use perlite in the garden:
- Perlite contains no nutrients and chemicals
- It allows light to pass through
- It aids in water retention while improving the soil drainage
- It retains its shape in the soil
- It has a neutral pH
- It helps to aerate the soil
Similarity Between Vermiculite and Perlite
There are several similarities between vermiculite and perlite, and our aim here is to know these differences.
- Both are naturally occurring materials that undergo certain processes to form their present state
- They are both lightweight
- Perlite and vermiculite are both relatively sterile
- They are highly porous, which helps them to retain moisture and nutrients for the plants
- They help in soil aeration
- They are both soil additives
Differences Between Vermiculite and Perlite
Even though vermiculite and perlite share some similarities, they are not the same as they have even more differences. These distinct features makes them valuable and their use particular to your needs.
#1. Moisture/ Nutrients Content
The moisture content difference in the two soil additives is one of the most significant differences between perlite and vermiculite. Vermiculite is a sponge-like tissue and can hold water five times its size. Its water retaining capabilities are far superior to what perlite can hold.
Vermiculite will hold more nutrients in its tissue than perlite in the same vein.
#2. Physical Attributes
Vermiculite is tan or brown. It looks like rough tubes or grains when dry and bloated worms when wet. It, is hard to distinguish between vermiculite and the soil when they are mixed together because of its color and shape.
Perlite, on the other hand, sports a white hue. It has a grain-like or ball shape when dry and then turns to a fluffy balls when wet. It can easily crumble into dust if decent pressure is applied.
#3. Chemical Attributes
Vermiculite undergoes ion exchange and can prevent overfeeding since it collects excess water and nutrients from the soil and stores them until the plants need the nutrients. Perlite, on the other hand, does not undergo any ion exchange.
Vermiculite holds a lot of water and so increases the amount of water in the soil. This makes it not great for drainage. Perlite, on the other hand, does not hold too much water and so is perfect for increasing the drainage of the soil. Perlite’s porosity will also allow excess moisture to drain out quickly.
Perlite aerates the soil and takes oxygen to the root of the plants. Vermiculite, on the other hand, does not open up the ground like perlite does not does it take oxygen to the roots.
Vermiculite Vs Perlite: Which is the Best?
This is the question many garden owners ask as they look for the best soil additive to use in their yard. The problem with this question is that it assumes they are substitutes. After going through this article, we know better. Since vermiculite and perlite are unique, we should instead be looking at the best time to use vermiculite and perlite.
When to Use Vermiculite
- Vermiculite is best used for plants that require damp soil at all times, like irises
- Use vermiculite if your garden is in a dry area or desert landscape so it can store water and release it slowly to the plant
- Add vermiculite if you use a porous pot that dries out too quickly, especially if the pot is placed outside
When to Use Perlite
- Use perlite if you’re growing plants that do not require a lot of water, like shade-loving succulents
- Add perlite to your soil if you want to loosen heavy and compacted soil
- Add perlite if your yard is in an area that sees a lot of water to prevent the garden from becoming waterlogged
Vermiculite Vs Perlite has remained a constant point of confusion for many garden owners for a long time, but thanks to this guide, you should be able to differentiate between them while knowing the best time to use each one.