“It’s important to use good quality liquid fertilizers in a vertical farm. It goes without saying that choosing the correct total hydroponic recipe for the crop type, humidity, temperature and the lighting used is very important,” says Roy O’Mahony, Co-founder and CTO at Cleangrow.
Based in California, US, CleanGrow designs and makes clear and precise liquid nutrients for CEA companies for their setup in bulk. “We are working closely with different types of vertical and urban farm equipment and lighting manufacturers to supply the best recipes for their customers. Growers can have a bespoke fertilizer solution for their system designed and delivered in bulk,” Roy notes.
Get your water right
According to Roy, mixing correctly with good quality water is key and regular QC checking of the solution going to and from the plants. A small error in a short life crop could ruin an entire cycle. It is also very important to keep clean lines. Different fertilizers are formulated for different crops. For instance, tomatoes will need a very different formula than typical lettuce. “In vertical farms sometimes multiple crops are grown at the same time. This can be tricky to get the balance right,” he adds.
Therefore, in a high throughput closed environment like a vertical farm, an influx of pathogens in the solution lines could be detrimental. “At CleanGrow, we have experts in-house that will dial in the most suitable solution for growers and take out that risk factor straight away, getting the supply chain sorted with clean and reproducible fertilizer sorted,” Roy affirms.
It's also very important to know your water, Roy continues. If it is not an RO (Reverse Osmosis) water supply, have it tested regularly to spot any changes fast. Then, check at least pH and EC (Electrical Conductivity) daily to spot any anomalies and address them quickly. It’s important to know when to change out the solution tanks depending on your system.
Cleangrow's 707 Nutrient line
According to Roy, the nutrient supply is the lifeblood of the entire system, so keep it clean. It’s easy to use something like a biocide and descaler to make sure lines and drippers etc. depending on the system for it not to get clogged. At the same time, make sure the solution in the main reservoir is kept at a stable temperature.
Whereas, in an urban setting maximizing the recycle times of the solution tank is important to save on time and effort and water costs and consumption. Na+ is element plants exude and can build up when recycling solutions, this can be tested easily and regularly. “The grower can get an idea of how far they can push the solutions in terms of recycling,” Roy adds.
Then there’s storage. Make sure to store your nutrient stocks correctly. Meaning, out of direct sunlight and temperature fluctuations so salts don’t drop out of solution. In terms of mixing, it always has to be done in the correct order. Thus, not locking out A and B solutions by mixing together in the concentrated form.
Another important thing is to remember that plants as well are great indicators of problems with fertilizers, keeping an eye out for any changes to leaf shape, stem size and leaf color can indicate an issue, it might not be the mix it could be fertilizer distribution to the crop.
From sensors to fertilizers
CleanGrow started off as a sensor company specializing in multi-ion handheld and automatic nutrient measurement devices for up to 8 ions including NPK rapid analysis on-site. “We set up manufacturing liquid fertilizers specifically for the hydroponic market in 2012 and have expanded a lot recently moving into a large facility in Vine Hill Sebastopol California,” Roy states.
In terms of monitoring fertilizer in a recycling system, CleanGrow sensors for auto analyzing the return solution make the modifications to the drain/return solution very rapid without the need for constant and expensive lab analysis reports.