Grow Media

What’s the best growing medium for plants?

The best growing medium for plants will vary depending on the species and growing method used. If you are using hydroponic growing techniques that require a substrate, soilless substrates such as coco coir, rockwool, hemp, and clay pebbles are very popular and allow for total control over the growing environment.

For container gardeners and those growing plants in beds outdoors, potting soil or mix provides the perfect growing media for healthy plants, and fruit and vegetables that are bursting with flavour.

Check out our guide on the best growing medium for an in-depth analysis of the pros and cons of the different types of substrates.

Soilless Substrates

For hydroponic systems, soilless substrates are usually preferred over organic material such as potting soils or mixes. This is because they are pathogen free, provide optimum drainage, aeration, and oxygenation, and can help to deter pests and disease. Roots easily intertwine around the media and are less likely to become compacted or suffer root rot due to oversaturation and compression.

Soilless growing media like coco coir, clay pebbles and rockwool are also pH neutral. This means that the growing medium won’t affect the delicate pH level of the nutrient solution. Another benefit is that they don’t contain any nutrients. As a result, this allows for much greater control over the amount of nutrients your plants receive.

Coco Coir Substrate

Coco coir is a popular soilless substrate derived from natural fibres from the coconut husk. It can be used as a standalone growing media or you can mix it with other materials such as clay pebbles or perlite. You can even mix it in with soil to improve its texture and drainage properties.

Coconut coir offers a wide range of benefits to growers such as an optimal balance of water retention, drainage, and aeration. It’s also pH neutral, so won’t affect your nutrient solution, and it has excellent cation exchange capacity (CEC) which means it can retain nutrients and release them to your plants over a longer period of time.

We sell the very best coco coir products from all the leading brands such as CANNA, Ecothrive, Biobizz, and Gold Label. Buy coco coir in bags, slabs, bricks, and pellets to suit your growing needs.

Clay Pebbles for Plants

Clay pebbles are small balls of clay that are kiln heated at high temperatures causing them to expand to create porous pellets that provide a versatile growing medium for hydroponic and soilless gardening techniques. They can be used alone or mixed with other growing media such as soil, compost mixes, coco coir, and rockwool.

Benefits of clay pebbles include excellent drainage, and aeration and oxygenation of the root zone to promote healthy root development and overall plant health. The pebbles are also free from pathogens, limiting the risk of pest invasions and disease. 

Due to their porous structure, clay pellets have the ability to retain both water and air within the micro pores, helping your plants to receive optimum moisture and air when they need it.

Rockwool Substrate

Rockwool, also known as stone wool, is an increasingly popular growing medium used in plant cultivation that is ideal for hydroponic systems and soilless gardening. It is a soilless substrate, and as the name suggests, rockwool is made from rock based minerals like volcanic rock that is spun into fine very fine fibres.

Due to the high temperatures used in its manufacture, rockwool is regarded as a sterile substrate that is free from pathogens. It is pH neutral, and its structure encourages uniform rooting patterns and provides the ideal conditions for moisture and nutrient distribution.

Available to buy in cubes,  slabs, and trays, it is compatible with most growing systems. At London Grow, we sell rockwool from all the leading international brands such as Grodan, and Cultilene, to ensure you can achieve superior harvests, time and time again.

Potting Soils & Mixes

Potting soils and mixes are the go-to growing media for urban farmers and green fingered gardeners that grow plants in containers, outdoor beds or allotments. Specially formulated to support plant growth and health, you can achieve excellent harvests and great tasting produce. 

Potting mix is a soilless grow media that contains a mix of compostable organic matter and other materials such as coco coir, bark, peat moss, perlite, and vermiculite. With a larger particle size compared to traditional soil mixes, potting mix provides good drainage, and excellent aeration and oxygenation of the root zone. 

The light texture of a potting mix won’t compact the plant roots, helping to minimise the risk of root rot and waterlogging. Mixes are ideal for container gardening, young plants and seedlings, and you’ll find a range of options with varying levels of pre-fertilisation to suit the needs of your plants.

Potting soil comprises of high-quality soil and organic matter, and is rich in minerals and nutrients. Due to the naturally dense texture of soil, potting soils are often mixed with other materials such as perlite, sand, coco coir, and vermiculite to improve drainage and airflow. In addition, these soils often contain pH balancers, fertilisers and wetting agents. 

As potting soil is denser than potting mix, it is not ideal for container gardening because it can compact the root zone. It is best suited as an improver for outdoor beds to enhance the quality of the natural soil.

If you’re looking for a quality substrate that does it all, the bestselling BioBizz All Mix won’t disappoint. This heavily pre-fertilised organic soil is loaded with nutrients to sustain optimum growth without the need for fertiliser for the first couple of weeks. It is carefully mixed to achieve a full micro active ecosystem to emulate rich outdoor soil and doesn’t contain any synthetic fertilisers. It has a high EC (electrical conductivity), and self-regulates to help maintain pH levels. All Mix is perfect for cultivating a wide range of organic fruit, vegetables and other tasty consumables.

For those looking for a quality mix but want more control over nutrient levels, opt for BioBizz Light Mix Potting Soil. This mix is based on virgin peat moss and is ideal for seedlings and young plants. It has a low fertiliser content to ensure the soil isn’t overloaded to reduce the risk of nutrient burn.

We sell a wide range of potting soils and mixes from all the leading brands including CANNA. Ecothrive, Gold Label and Plagron, and more, to help you achieve blooming crops and excellent harvests.

Order Growing Media Online for Delivery or Collect from Our Superstore

Whatever grow media you need, you’ll find it right here at London Grow. Whether you are growing indoors or outdoors, we have the perfect substrates for your plants and growing method. If you need any help deciding on the best growing medium for your plants, either pop into our store or contact us for expert advice.