Growing Food…Without Soil

David Stack
4 min readMay 5, 2017

Have you ever wondered where your food comes from? Think it all grows in the ground?

Think again.

If you’ve ever seen a head of lettuce with its roots still attached, or purchased a tomato in the middle of winter at the grocery store, chances are both were grown without soil.

Hydroponically grown lettuce (source: ediblegarden.com)

Every year, more and more food is grown using a soil-free, water based growing method called hydroponics. From massive commercial production facilities to backyard gardeners, growing plants soil-free is becoming increasingly popular around the world.

Why is soil-free so beneficial?

NO MORE GUESSING HOW MUCH TO FEED AND WATER

One of the fastest ways to kill a plant is by giving it too much or too little water or fertilizer. Soil-free growing allows precise control over both of these factors.

FASTER GROWTH

In soil, a plant’s roots need to spend energy to seek out nutrients. However, in a water-based system, the nutrients are delivered directly to the roots. This allows the plant to spend more energy to grow it’s leaves, stems, and flowers. Additionally, the growing environment can be more easily controlled, which leads to more favorable conditions for the plant, enabling faster growth.

NO WEEDS

In soil-free gardening, there’s no extra space for weeds to grow, so no need to spend back-breaking time pulling them out, or spraying dangerous herbicides to kill them.

FEWER BUGS AND LESS DISEASE

Because plants aren’t grown in the ground, many bugs simply don’t have the space to reproduce (insects lay their eggs in soil), or they often can’t reach it in the first place. Any soil-related diseases are completely a non-issue in soil-free gardening as well.

FEWER (OR NO) PESTICIDES

Because there are overall less pests and diseases (see above), there is much less need to apply pesticides — if they even need to be applied at all!

LESS WATER

In traditional growing, water is poured over the ground and seeps into the soil. Only a small fraction of the water actually gets used by the plant.

LESS SPACE

Plants grown using soil-free methods have smaller root systems and thus can be grown closer together.

CLEANER AND EASIER TO MAINTAIN

Without soil, there’s no foul odors or mess. In some soil-free systems, watering can be automated, so you don’t have to worry as much about leaving your plants unattended while on vacation.

MORE RESILIENT GROWING YEAR ROUND

While not specific to hydroponics, growing plants indoors in a controlled environment is much easier to do without soil. This has the added benefit of preventing losses due to unpredictable weather and changing climate conditions.

PLANTS CAN BE GROWN ANYWHERE — EVEN IN SPACE!

Soil-free growing has been continuously developed by NASA for decades. In fact, astronauts aboard the International Space Station grow their own soil-free food. How cool is that!

Hydroponic lettuce grown in space. Space!

Soil-free gardening is great, but it’s not perfect.

While the technique of growing plants in water has been around for thousands of years, it has only been in the last few decades that it has become so cost-effective and popular. However, there are still a few drawbacks:

REQUIRES A DIFFERENT SKILL SET AND KNOWLEDGE

Most people have learned (at least in theory) how to grow a plant in soil using conventional methods. The issue with growing without soil is that many people have no idea how to even begin growing this way — it has to be taught. On the other hand, there is plenty of knowledge for soil based growing that’s not needed in soil-free gardening (e.g. soil texture, soil borne diseases and pests, tilling, crop rotation, etc.).

INCREASED CHANCE OF FUNGI AND MILDEW

Because of the water, humidity levels can be higher when growing soil-free. If it’s not controlled, this can increase favorable conditions for fungi and mildew, which can kill plants and cause allergies. This depends on other environmental factors too, and can be managed, but is something to be aware of. A clean growing environment reduces this risk.

WATER-BASED MICROORGANISMS CAN BE EASILY INTRODUCED

Due to the water only nature of soil-free gardening, plants grown this way are at a higher risk of potentially harmful water-borne microorganisms spreading rapidly throughout the system. However, keeping the water reservoir temperatures cool (under 80°F) and oxygen levels in the water high can greatly reduce this risk.

REQUIRES AN INITIAL INVESTMENT

Because soil-free gardening is based on a growing system, it requires some up front investment. You can’t just go buy some seeds and plant them in the ground like you can with traditional soil based gardening. Though it can be a bit more of an investment up front, it can pay for itself in the long run.

In the future, more of our food will be grown soil-free.

While soil-free gardening isn’t perfect, the downsides can be minimized with proper care, preparation, and further technological development.

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David Stack

Full stack software engineer and entrepreneur. Let’s solve climate change by upgrading our systems.