Hydroponics - extended version

I’ve never been a fan of hydroponic gardening. It seems to clinical for my dirt-under-the-fingernails approach to growing things - too much measuring and monitoring for someone (me) who likes to hand everything over to nature once I’ve started the process off. Keeping an eye on light levels, nutrient concentrations, flow rates and so on is more engineer that horticulturalist by my reckoning but there are those who love it and devote whole glasshouses to the science of raising vegetables in a stream of running water. Those that I have visited remind me of the tropical glasshouses that are found in the centres of Botanical Gardens throughout the world. They seem unreal and exotic. Tiny pumps hum. Water flows in a series of miniature waterfalls, the leaves of plants seem oversized and extra-juicy. I expect to hear the call of howler monkeys and the patter of the feet on elusive jungle-creatures.

Mostly though, I’ve seen lettuces. Very green lettuces and fully leafed, all up and running, nothing limp or grubby with dirt - everything’s clean. There’s no soil there at all, just some sort of medium, sand or perlite or some synthetic grains that anchor the roots of whatever’s growing in the stream beds (they are probably called tubs or pools or tanks, I didn’t ask. It all looks quite appealing and if you’ve ever kept tropical fish in a tank, you’ll get a familiar feeling from the hydroponic set-up. There are thermometers too, so temperature is as important to the water-vegetable growers as it is to those of use who cultivate dirt.

There’s no question that hydroponics produces a lot of ‘matter’, mainly in the form of leaf. The cannabis growers wouldn’t be so interested in the method if it didn’t I suspect. They’ve inadvertently brought the technique into some disrepute recently, having drawn attention to the efficient, high-production process of feeding nutrients directly to the roots of the plants, by passing the ‘feed the soil’ stage, through the media and police ‘interest’ that high-return, illegal crops like cannabis seem to attract.

Many a home hydroponic grower must have cringed as those scenes played out on screens of televisions across the country and many a neighbour may have looked a little more closely at the bubbling, dripping set-ups over the fence, most of which would have been entirely bona fide.

My greatest reservation about the hydroponic system has always been its reliance on straight-from-the-lab chemicals. I’m an ‘organic’ grower and like to feed my plants with composts, manures and liquids that are made on site with methods nature has employed for millennia. Bottles of H2So7 or what ever is poured into the feed tubes in a hydroponics glasshouse don’t pass my ‘natural foods’ test but that’s not to say they don’t produce fantastic results - they do, from what I’ve seen and it could be argued that a system whereby plants, anchored in gravels, extracting their sustenance from nutrient-rich water flowing about their roots, is natural and describes exactly what water cresses do, and wasabe and other wetland plants, edible and otherwise. So it’s not entirely a synthetic environment, it’s just that you don’t often see lettuce, tomato and brassica growing in mountain streams.

I’ll be accused of ignorance here I suspect. Practiced hydroponic growers will lay down their bottles of drip-feed and un-shoulder their sacks of ’growth medium’ and take up their righteous pens of Indignation and Re-education and put me straight - I hope so anyway. They are clearly masters of an art whose value I am missing and I would like to learn more about it.

But for now, I’ll stick with running soil through my fingers, rather than my fingers through the greenish waters of a hydroponic stream and enjoy the thought that if the electricity goes off, I’ll not lose my lettuce crop.