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There is a lot of discussion in gardening circles about how loam soil is the ideal growing medium for plants. How does this relate to ericaceous compost? Is it loam-based, and does it offer the same benefits?
Not all ericaceous compost is loam-based. Some ericaceous composts have loam soil added to the organic compost material to increase the rooting structure for the plants and provide a balanced water retention substrate to provide good drainage and water-holding capacity for plant health.
Ericaceous compost is ideal for certain plants, but compost does not generally have soil included in the mixture. Where doe loam fit into the picture with ericaceous compost? Is this compost loam-based, and can you use it as a growing medium?
Does Ericaceous Compost Contain Loam?
As a general rule, compost does not contain soil, even though it may look like soil when it is mature and fully decomposed. This standard applies to ericaceous compost, too, so what is meant by loam-based ericaceous compost?
As a quick recap for people who may not be entirely familiar with what ericaceous compost is, it is normal compost with a higher pH value. It is used to amend the soil pH for plants that prefer an acidic growing environment that grows poorly or even dies in alkaline soils.
While amending the soil pH, the organic material in ericaceous compost provides the nutrients required by the plants.
So let’s get back to whether ericaceous compost is loam based or not.
What Is A Loam-Based Compost?
Loam is a term usually applied to soil and is used to describe the texture and structure of the soil. Loam soil is the “holy grail” of soil because it is perfectly balanced soil that gives plants the right amount of water retention and drainage to promote healthy growth.
Loam soils consist of equal parts of the following soil types:
- Sand. Sand provides bulk for the mixture and a good rooting structure for the plants.
- Silt. Silt is a loose granular mix in the soil that improves drainage and aeration.
- Clay. Clay is a fine-grained component that improves the soil’s water retention capacity.
The equal parts of these inorganic soil types create a balanced plant-growing environment. Loam soil offers the plants good soil structure for rooting and retaining just the right amount of moisture to keep the plants happy.
The balance in water retention sustains the plants without allowing them to dehydrate or, on the other end of the scale, become waterlogged.
Loam soil provides the ideal soil structure for plants to grow but does not provide much in the way of nutrients. Organic matter is required in the loam soil to provide the nutrient balance required for plant growth.
A loam-based compost refers to a mixture of inorganic loam soil and organic compost to provide everything a plant needs in a growing environment. The soil provides structure and water retention, while the compost provides nutrients.
So what does loam soil have to do with ericaceous compost?
Most composts do not have a soil component and are purely organic materials in various stages of decomposition. Ericaceous compost falls into this category, meaning they are not generally loam-based.
Loam-based ericaceous composts are available, but they are generally expensive and much more difficult to transport due to the additional weight from the soil in the mixture.
Are All Ericaceous Composts Loam-Based?
Most ericaceous composts are not loam-based, meaning they cannot be used as a growing medium for your plants but are used as an additive or soil amendment medium.
Standard ericaceous compost must be added to your garden bed or your potting mix to adjust the pH value to the acidic side of the scale.
This type of compost does not have a soil-like structure to support the plant’s root system, and the ph value of the compost may be too acidic to be used as a growing medium.
In contrast, ericaceous composts that are loam based are a mixture of ericaceous compost and balanced loam soils. These products can be used directly as a growing medium rather than a soil amendment product.
How Does Loam Benefit Ericaceous Compost?
When loam soil and ericaceous compost are combined, you have a growing medium that includes the inorganic components of soil as well as the organic component of compost.
Ericaceous loam-based compost is a mixture of loam soil and ericaceous compost, and it can be used as a direct growing medium for plants that prefer acidic growing environments.
Loam-based ericaceous compost is generally not used in a garden bed but is intended to be used as a potting mix for acid-loving plants.
If you are growing your plants in a garden bed, standard, non-loam ericaceous compost would be the better choice, especially from a cost-effectiveness standpoint.
Any loam-based compost offers benefits by providing a good rooting and moisture retention growing medium for plants with the added benefit of organic matter provided by the compost.
Most ericaceous composts available are standard composts with no soil added. They are intended to be mixed together with your own soil or used on top of the existing growing medium.
Some garden centers stock loam-based ericaceous composts, but they are unavailable in all centers. These composts are typically heavier due to the soil content, making them difficult to source online due to the higher delivery costs.
You can create your own loam-based ericaceous compost by buying a loam soil mix and adding ericaceous compost to add nutrients and amend the soil pH.
How To Make Your Own Loam-Based Ericaceous Compost
If you cannot source a ready-made loam-based ericaceous compost, you can make your own version as a potting mix at home.
You need the following ingredients to make your own ericaceous growing medium.
- Ericaceous compost
- Normal compost
- Perlite
- Garden soil
- Sand
Most garden soils have some aspect of loaminess but need adjustment to improve the characteristics. This means you can use soil from your garden as the garden soil ingredient rather than a commercial product if you have relatively good garden soil.
Mix the ingredients in the following ratios.
- 50% ericaceous compost
- 10% normal compost
- 20% perlite
- 10% garden soil
- 10% sand
This mixture will provide an ideal growing medium for growing acid-loving plants in containers or pots or planting directly into garden beds.
Some sources advocate using peat instead of ericaceous compost, but this is a limited natural resource, and the planet and natural habitats are being harmed by peat harvesting.
Conclusion
Loam-based ericaceous compost is a mixture of loam soil and ericaceous compost designed to provide a suitable growing medium for plants that prefer a lower pH environment.
Most ericaceous composts are not loam-based and only include the organic matter in the mixture, without the inorganic loam soils.
Sources
- https://www.gardeningknowhow.com/composting/basics/ericaceous-compost-info.htm
- https://positivebloom.com/loam-based-compost/