Soilless growing, hydroponics, vertical farming

When you hear 'soilless growing', the first thing that comes to mind is sterile laboratories with perfect plants. In practice, it's dirty rubber boots, constant battle with algae in the tanks and those eternal pH problems. I remember how in 2018 we launched an experimental vertical farm in the suburbs of Novosibirsk - we thought we had recreated Dutch technologies, but what we got were stunted sprouts with chlorosis. It turned out that they had forgotten about the daily temperature fluctuations in the unheated hangar.

Hydroponics: more than just water and fertilizers

Most people think of hydroponics as simply watering with a nutrient solution. In fact, this is an exact science - I still keep a notebook with notes on the electrical conductivity of solutions for different crops. For example, for basil the optimal EC is 1.8-2.3 mS/cm, but if the night temperature drops below 16°C, the concentration must be reduced by 15%, otherwise the roots will begin to die.

We are currently working withShandong Linyao Intelligent Agriculture Technology Co.,Ltdover the automatic control system - their equipment does a good job of maintaining pH, but there are nuances with the adjustment by time of day. Their website https://www.lyzhihuinongye.ru has interesting solutions for integrating water and fertilizers, although the algorithms had to be modified for Russian conditions.

The most common mistake newbies make is skimping on filtration. We once installed a cheap disk filter on a drip irrigation system - after a month all the emitters were clogged with sediment. I had to completely change the line, which cost more than ten high-quality filters.

Vertical farming: where mathematics meets biology

Calculating light fluxes in multi-tier systems is a separate headache. Lumens, lux, PAR - all this needs to be translated into practical indicators. For lettuce, the optimal PPFD is 150-200 µmol/m2/s, but when the rack height is more than 50 cm, the lower tiers receive 30% less light.

In the projectShandong Lingyao Co.,LtdDuring the construction of smart agricultural parks, we were just faced with the problem of shading. We had to develop a custom system of moving lamps - it was expensive, but it increased the yield by 17%.

The most difficult thing about vertical farming is not the technology, but the logistics. Harvesting from the fifth tier while dragging a stepladder is still a pleasure. Now we are trying conveyor systems, but so far they are more of a hindrance than a help.

Equipment: between 'smart' and 'working'

Automation in soilless growing is often a nightmare. pH sensors require calibration once a week, EC sensors get coated, and smart valves sometimes forget to close. One night the controller failed and by morning the whole salad was floating in a solution with EC 5.8.

UShandong Linyao Intelligent Agriculture Technology Co.,LtdThere are good developments in remote control of valves, but in the conditions of Russian voltage surges it was necessary to install additional stabilizers. Their water filtration system has proven to be better than many European analogues, especially when working with hard water.

Frequency converters for pumps are a must have for any serious hydroponic system. Without them, pressure drops kill IVs within a couple of months. We learned this at great cost - after the third replacement of the entire irrigation system.

Nutrient Solutions: The Alchemy of Modern Farming

Making a solution is not just mixing components A and B. It is necessary to take into account the stage of plant growth, temperature, humidity and even wind speed (for open systems). In the summer of 2020, we lost our entire tomato harvest due to the fact that calcium levels were not adjusted due to a sharp increase in temperature.

Microelements are a separate topic. Iron must be in chelated form, otherwise it precipitates. Copper and zinc are needed in microdoses - too much of 0.1 ppm already causes toxicosis. It took a long time to select the ratio for strawberries - it turned out that they need 30% more potassium during the fruiting period than indicated in standard recipes.

Now we are experimenting with organic additives for hydroponics - so far unconvincing. It seems that growth is improving, but this does not add stability to the system. This might work better for aquaponics.

Real cases and failures

The most successful project is a greenhouse complex near Kazan, where hydroponics and vertical beds were combined. The lettuce yield was 6.8 kg/m2 versus the usual 3.2 in the soil. But the cost is still high - energy costs for additional lighting eat up 40% of the profit.

But the attempt to grow strawberries in a multi-tiered installation failed completely. There was not enough light even with a lamp density of 350 W/m2, and the flowers had to be pollinated manually - unprofitable. We had to repurpose the system for green ones.

We gained interesting experience while working withShandong Lingyao Co.,Ltdon the project of high quality agricultural fields. Their smart equipment technologies have proven to work well in large greenhouse complexes, although they are difficult to maintain for small farmers.

Prospects and dead-end branches

Soilless growing is definitely not a panacea. For grains or root crops it is unlikely to ever become profitable. But for greens, medicinal herbs and some vegetables, it is already more profitable than traditional methods.

Hydroponics in its current form, I think, will soon give way to aeroponics - less water consumption, better aeration of the roots. But for now it is too expensive and capricious.

Vertical farming makes sense only in conditions of expensive land and developed logistics. Building vertical farms in regions where a hectare costs pennies is economic madness.

Now we are seeing an interesting trend - combined systems, wheresoilless cultivationis adjacent to traditional methods. Perhaps this is the future - not a complete abandonment of soil, but a reasonable combination of technologies.