A hydroponic substrate or medium is the material in which you grow your plants instead of soil. There are many types of substrates and mediums which you can choose from and this is a very important decision! In fact, hydroponic substrate & medium selection is one of the most important decisions you’ll make as a grower because it impacts how your plants will grow, how they will fit into your system, and what type of labor and costs are involved in growing your plants.
The commercial sector relies heavily on starter plugs, plug trays and tray warmers for successful germination and cloning and many home growers are also understanding the benefits that a grow plug offers.
Polymer-bound flexible plugs have been the common choice over the past decade, especially for systems with recirculating irrigation (like hydroponic systems) and those with limited space. They incorporate an organic material like peat or coco coir and bind it together with a polymer—picture a rubbery glue. This makes the plug very contained.
Other media for growing hydroponically are coco coir, derived from coconut husks and rockwool, made from spun molten basaltic rock.
A full circle sustainable product
In today’s eco-conscious world you may be looking for substrates that limit impact on the environment as much as possible.
There were few alternative products on the market until Dutch start-up GROWFOAM® launched a sustainable & biodegradable option in recent years. Founded in 2018 and manufactured in The Netherlands, GrowFoam operates their business with carbon neutral practices.
The revolutionary foam based substrates offer a multitude of eco-friendly benefits for hobbyist and commercial hydroponic growers alike.
For starters, they are biodegradable polymers and natural additives, with no microplastics and no PFA’s allowing them to be TUV Industrial Composting Certified.
“Growfoam substrates are 100% biodegradable and the production of our substrates is completely free of waste”, explains Neils Steenvoorden, CCO of GROWFOAM®. “All residual materials are re-used as a base material for new substrates. After degradation -at home or in an industrial recycling plant- Growfoam substrates leave nothing but water and CO2. Of course our CO2 footprint is 100% compensated.”
While some may be skeptical of growing with no soil in sight, performance of the GROWFOAM® substrates equals that of traditional peat moss plugs and produces healthy root development. In addition they provide a stable micro bio-environment of water, without the chance of overwatering, leading to fewer losses in production.
Pure- fresh produce
Unfortunately, it’s commonplace now to hear news stories and data based reports about contaminated food supplies. The demand and pressure is increasing not only for people to know where their food is grown, but also for clean and pathogen free vegetables.
Because there is no opportunity for contamination in the water system, GROWFOAM® plugs are deemed a clean alternative- Free of e-Coli, listeria and other bacteria allowing farmers to produce “no wash” food.
Steenvoorden went on to explain how producers also have the option to harvest and package the crops with the substrate attached and be sold to the consumer this way. “Keeping the substrate in a small layer of water allows consumers to keep the crop healthy, fresh and growing for a couple of extra days when the Growfoam plugs stay attached after harvesting the crops.”
How do they work?
GROWFOAM® substrates are suited for automated and manual DFT, aeroponics, NFT, deep water culture, gutter and float systems and are fully compatible with ZipGrow technologies. They guarantee no soil in filters – ever.
The substrate does not contain or buffer any nutrients, allowing you to fully control nutrient dosing. Unlike peat-based plugs that can vary in concentration of nutrients, GROWFOAM® plugs are all created equally, allowing the grower to optimize nutrients and set those parameters only once. This consistency of production also provides less logistic and storability risks.
The plugs that have a lightweight and spongy texture require full saturation before sowing for less than a minute and current product forms have an average water holding capacity of 65%. This means 35% of the space is air available to the roots, making Growfoam® ideal for many different crops.
GROWFOAM® is a scale-up company and is one to watch. They are consistently improving on innovations of premium substrates at their two green simplicity grow containers in Groningen, The Netherlands. In 2021, they were a rising star nominee in Deloitte Fast 50 and nominated for the ‘Most Disruptive Technology Award’ placing in the top 10 out of more than 80 participants.
You can discover more about Growfoam and follow their advancements on their website, Linkedin and Instagram page.
View the GROWFOAM® brochure here.
