Who needs soil anyway?

By Harry Wright

"I could never get my head around when to water plants, when to fertilise, what type of soil to use for which plants, so decided to give hydroponics a go, removing many of the variables that I had been struggling with and giving me more control of the plant health."

How it all began

What could this picture of some dying chilli plants have to do with hydroponics? Well this was what got me interested in hydroponic growing techniques. My family has always had a knack for gardening and growing food. My mom has always had a stunning garden, with produce growing amongst indigenous shrubs and flowers. My brothers would always send pictures of their amazing chilli, tomato and fruit harvests and then there was me, with my dead chilli stalks.

Growing up in South Africa, the weather can be quite tough for growing plants, with high summer temperatures and evening thundershowers that would drench the soil. I could never get my head around when to water plants, when to fertilise, what type of soil to use for which plants, so decided to give hydroponics a go, removing many of the variables that I had been struggling with and giving me more control of the plant health (at least that’s what I thought). The “maker” in me was also excited to be able to build a hydroponic system for growing crops.

What is hydroponics?

If you do not know what hydroponics is, it is a method of growing plants without soil. Instead of plants extracting nutrients from the soil, you add nutrients to the water that you feed the plants. There are a few important things plants need and for a plant to thrive - they need the following: Firstly light (not a problem in South Africa, more so in the UK, however supplementary lights can be used if required), next is a carbon source (CO2), an oxygen source (air and water), a hydrogen source (water) and nutrients including nitrogen, phosphorus and potassium (NPK) as well as more minor elements which are added to the water.

I read a few articles online, followed a few YouTubers and decided to have a go at building my own systems. I decided to try a technique called flood and drain, where plants are grown in a clay media, with the nutrient level rising and falling allowing the roots to absorb water and nutrients when the level is high and absorb oxygen through the roots when the level is low.

I also wanted to try a drip technique or Dutch buckets where the nutrient solution is fed via a dripper to the base of the plant, again allowing some of the roots to be in contact with nutrient solution and some in contact with air allowing them to absorb oxygen.

I loved the process of building the systems and if you enjoy any kind of “making” I would definitely suggest building your own systems. If you are interested in either of my builds, feel free to see what I did on Instructables (a great resource for making just about anything) - links available here and here. If some of the pictures of the build look intimidating or at this point you are thinking it all sounds too complex, that is definitely not the case. Hydroponics can be an incredibly simple process, with the required system only as complex as you wish.

It's easy to start, and you don't need much space!

Have you ever put store bought herbs in a glass of water and noticed roots forming, or taken a plant cutting and rooted it in water? Well that is hydroponics. If you add some nutrient to that water, chances are the herbs would grow continuously, allowing harvest after harvest instead of buying new herbs each time. Got some spring onion end cuttings? Well pop them into a feta container filled with water and a weak fertiliser and you have a continuous supply of spring onion. Love the little garnish microgreens you get in restaurants? Well good news, they only take 5 -7 days from sowing seeds until harvest.

Only have a small dark part of your house/ apartment where you have space? Well there are very affordable systems available online, costing less than £40 with supplementary lighting. One of these systems kept us going with lettuce all through the first COVID lockdown. Due to these systems small footprint I have one on my office desk as well, growing mint for tea and chilies (although they were a bit big for the system) for spicing up my lunch.

Variety of seeds available

One of the things I loved the most about now being able to grow my own food, was the variety. Go onto any seed website and you will be met with hundreds of tomato varieties, chillies ranging in heat from red peppers all the way up to something as “spicy” as pepper spray, herbs you have likely never heard of and all kinds of weird and wonderful plants. Whether you grow hydroponically or in soil, there is nothing quite like having friends or family over amazed by the strange looking, strange tasting produce growing in your garden or house. Although if you would prefer you need not buy seeds, save them from store bought fruit and veggies, trade them online or at local swaps.

Some of the more exotic things I’ve grown include: Lemon cucumbers, weebee pumpkin, cinnamon basil (a strange experience), chocolate tomatoes, pear shaped tomatoes and the strangest of them all - a flower that goes by several names: electric daisy/ buzz button/ tingflowers (Acmella oleracea). The sensation of eating an electric daisy is hard to explain, I will leave it to you to grow and try some.

Cooking with your own produce

Growing the produce is only half the fun. Making dishes based on your home grown produce is an equally rewarding experience. We have had delicious babotie (a national dish in South Africa) inside a home grown baby pumpkin, pickled our own lemon cucumbers (fermentation, something else I wholly recommend people try doing with home grown produce or even store bought), and made plenty sheba (South African tomato relish) which we gift to friends and family every year.

Moving from South Africa where we had a lot of space into a two-bedroom apartment in Sheffield meant that for the most part all my hydroponic systems have been downsized. Now our windowsills are permanently full of used yogurt tubs, feta pots, or purpose bought hydroponic setups. We even tried a tomato, which eventually claimed the entire window to itself. Commercial Hydroponic farms exist for several reasons, but one of the main ones is the fact that you can grow plants close together to increase the yield, a benefit anyone can take advantage of. Any empty surface in your apartment/ house/ office/ cellar/ loft is all of a sudden a possible plot of land, limited only by your imagination.

Mental health benefits

The benefits of growing plants at home extend way beyond the calorific value of the plants grown. Anyone who has watched a cutting root, watched a seed grown sunflower flower, eaten the first leaf of lettuce from their home grown crop or simply taken a five minute break from their work to water their plants knows the joys that plants can bring. In addition to growing food hydroponically, I am also an avid houseplant enthusiast (as anyone who has seen our apartment would know) and although their air improvement ability is often oversold, mental health benefits of owning plants are undersold. Indoor plants offer a refuge from the outside world, a safe place where you are able to nurture a piece of nature and watch it grow into something beautiful. If these plants are edible, you gain the additional benefit of saving some money on your dinner.

We actually still need soil

I do need to address the title of this blog: “Who needs soil anyway?” Well the answer is we all do. Almost all of our food, especially grains are grown in the soil and will be for the near future. Soils globally are degrading due to deforestation, overgrazing and excessive use of agrochemicals. Hydroponics offer the soil a break, a way to grow food in places where the soil is already unable to support crop production, giving the soil time to recover.