Hydroponics is one of those techniques for growing that really seems to capture our imagination, particularly with the slew of CGI images of futuristic vertical farms set atop skyscrapers that flood social media these days. Yet you don’t have to have an engineering degree or a glass-covered penthouse to try this out for yourself. So here’s my beginners’ guide to home hydroponics.
Hydroponics can be as simple or complicated as you want, but at its heart is the fact that plants do not need soil to grow. Generally speaking, the only thing soil provides for plants is a source of moisture, air and minerals – roughly in that order. Dispensing with soil means you can grow in clear glass vases or bowls without any growing media whatsoever.
If you are an indoor gardener like me, this not only means less potential for dirt and mess, but also removes questions about over- or under-watering, and allows you to appreciate the architecture of the roots, all too often hidden from view.
Almost any plant can be grown this way; however, there are candidates that are particularly suited to the technique – and ones which also have attractive roots. Perhaps the best example is the moth orchid, phalaenopsis. All you need do is gently lift your plant out of its pot and tease away any bark chips from around its root ball. Snip off any roots that are brown or shrivelled and lower the plant into a glass container. Fill the vessel up with water until it covers the bottom third of the roots, leaving the top third in the air and, hey presto, you are done!
The same technique can be used on a huge range of plants in the aroid family, too, from monstera to philodendron, alocasia to epipremnum, as well as some of the cane begonias such as B maculata and even the lucky bamboo, Dracaena sanderiana. I take these plants out of their pots and carefully wash off as much growing media as I can from the roots. Leaving them overnight in a bucket of water softens up the last traces of compost, which can then be blitzed away with a spray bottle to reveal pure-white roots.
These terrestrial species need less airflow at their roots than epiphytic moth orchids, so I keep the water at the same level as the original compost, totally covering the root zone. If you live in a hard-water region, bottled water is a good option to keep the glass clear and free of limescale. All I do each week is top up the glass to the original water level.
What about nutrients? Once a month I give them liquid fertiliser instead of plain water, leave the plants to absorb this overnight, and rinse them out the next day. It’s all very straightforward stuff to create a quirky indoor display.
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