Perlite and LECA are two options you can use to help grow a variety of plants, but which one is best?
In my experience, perlite is a great addition to the soil to make it drain better and is ideal for plants that are at risk of root rot. LECA, on the other hand, is great when used as its own substrate for epiphytes like pothos.
One isn’t really better than the other, they just have different applications that they excel at.
Contents
Overview of Perlite and LECA
Before we get into the comparisons between these two substrates, let’s explore their origins first to get a better idea of their applications in gardening.
Perlite: Description And Origin
Perlite is a type of volcanic glass formed when obsidian, a natural volcanic rock, comes into contact with water.
When heated, this glassy mineral expands, turning into the lightweight, porous, and white material you typically see in potting mixes and gardening stores. Its main benefits include:
- High porosity: Perlite’s airy structure allows it to hold air very well.
- Excellent drainage: Its porous nature also helps prevent overwatering while retaining a limited amount of moisture that your plants need for growth.
- Sterile and pH neutral: You don’t have to worry about pests or diseases hiding in Perlite, making it a safe choice for your delicate plants. Also, its neutral pH between 6.6 to 7.5 is ideal for a variety of plants.
LECA: Description And Origin
LECA, or Lightweight Expanded Clay Aggregate, comprises small clay pebbles formed by heating natural clay to extremely high temperatures.
LECA is a manufactured product that has become more popular over recent years. I myself have tried using LECA to grow a variety of plants such as Anthuriums and Pothos.
Here are some advantages of using LECA in your gardening projects:
- Lightweight: The low weight of clay pebbles makes them easy to handle and perfect for vertical gardening or plants requiring frequent relocation.
- Enhanced aeration and drainage: LECA’s porous structure provides excellent oxygenation to plant roots and helps prevent overwatering issues.
- Reusability: You can wash and reuse LECA, making it an eco-friendly and budget-conscious choice for your gardening needs.
Now we have a better idea of what both of these things actually are, let’s see how they compare.
Key Similarities
Here are the key similarities between Perlite and LECA.
Aeration And Drainage
Both Perlite and LECA provide excellent aeration and drainage for your plants.
These substrates have a porous structure that helps to promote oxygen flow while also ensuring proper water drainage. By using either of these materials, you can prevent common issues like root rot and overwatering.
Aeration is crucial for healthy plant growth, as it allows the roots access to the oxygen needed for effective nutrient uptake. Both Perlite and LECA allow for efficient aeration, ensuring your plants have the best chance at success.
Soil Structure Boost
Perlite and LECA can both be added to soil to improve consistency by reducing soil compaction.
Perlite is used for this more often, but LECA can also be used as well. Reducing soil compaction promotes new root growth and also contributes to improved drainage as well.
Key Differences
Now let’s see how these two are differentiated from each other.
Physical Properties
Perlite and LECA have different physical properties that set them apart.
Perlite is a white, lightweight, and porous volcanic glass that is formed when obsidian gets heated rapidly. It is usually quite soft to the touch, and you can easily turn it into dust if you rub it together in your hands, especially if it is wet.
On the other hand, LECA (Lightweight Expanded Clay Aggregate) consists of small, round, clay pebbles that are baked at high temperatures, causing them to expand and become porous. They are generally brown or reddish-brown in color and much harder/long-lasting.
While both materials have a porous nature, LECA is heavier and more stable than Perlite, making it suitable for anchoring plant roots in hydroponic systems.
Water Retention
Perlite boasts excellent drainage properties, so it doesn’t retain much water. This characteristic makes it ideal for plants that require well-draining conditions, like succulents and cacti.
However, LECA exhibits better water-holding capacity, as the porous clay balls can absorb and store moisture. It is ideal for plants that need a balance of moisture and air around their roots in hydroponic systems (epiphytes mainly).
Applications
When it comes to gardening and horticulture, both Perlite and LECA offer various benefits and applications.
In this section, we’ll explore their roles in potting mixes, seedlings and succulent care, and soil amendments and aeration.
Potting Mixes
Perlite is a popular additive in potting mixes due to its ability to improve drainage and aeration. By mixing Perlite into your potting mix, you can prevent the soil from becoming too compact, which allows plant roots to grow more easily.
LECA can also be used in potting mixes to improve drainage and aeration, and it is also a popular option to use entirely on its own.
Seedlings and Succulent Care
When it comes to seedlings and succulent care, both Perlite and LECA can support healthy growth. Perlite is often preferable for seedlings, as it promotes excellent drainage and reduces the risk of root rot.
Likewise, LECA is a great option for succulents, as it encourages proper drainage and aeration while reducing the risk of pests.
In Summary
If you’re looking for an addition to your soil, perlite is a better option.
LECA can also be used, but it will hold on to more moisture and is more suited for being used as a potting mix itself for epiphytal plants.
Both are great options and something that every gardener should be aware of, but there isn’t really a clear winner when you compare them directly.
