There is more than one way to garden. Growing plants hydroponically is great for those wanting to have more control over the growing environment. And when done right, it can help save time, water and space, and increase the yield, too.
Hydroponics is a way of growing plants without soil. Instead, plants are grown in a soil-less medium, like perlite, vermiculite, clay aggregates, coconut coir or recycled glass. Unlike soil, these media are void of any nutritional benefits, so plants need to be fed regularly with a nutrient solution (hydroponic fertiliser diluted in water) to keep them healthy.
Growing plants hydroponically eliminates most of the issues we face growing in the ground or potting mix. This includes soil-borne pests and diseases, including curl grubs, root rot and damping-off, and weeds. Also, it helps conserve water as water goes directly to the roots, instead of potentially running off or being siphoned by other plants.
While the benefits are great, note that setting up a new system does take time, patience and money. There can be a little trial and error to get it all going. However, once it’s all set up, it’s easily controlled and can be automated, if needed.
There are various forms of hydroponics – they all differ slightly in the way that plants access oxygen and the nutrient mix. Plants may be grown in pots or containers part-filled with the nutrient solution (part filled to ensure there is still plenty of oxygen for the roots to access). Once the solution depletes to a certain level, this is topped up. Plants may also be grown in pots but have access to an external reservoir filled with the nutrient mix. Both these methods are known as passive hydroponics or hydroculture.
Other methods include nutrient film technique (NFT), flood and drain, deep water culture, and aeroponics. With these methods, the nutrient solution is typically pumped to the plant roots and cycled back to a reservoir – this flow may be continuous or at programmed intervals. These techniques are generally used in commercial horticulture or by hydroponic enthusiasts. You may want to start with a ready-to-use kit before moving onto more advanced systems.
To prepare the nutrient solution, you will need a specific hydroponic fertiliser and a pH test kit. Measure the pH of water and adjust with pH down or pH up solutions to bring it to 7.0 (neutral pH). Add the hydroponic fertiliser as directed and adjust the pH according to your plant’s needs. For most leafy greens, the pH should be between 5.0–6.0. For most fruiting plants, like tomatoes, chillies and eggplants, the pH varies between 5.5–6.5. This ensures nutrients in the solution are readily available to be taken up.
Depending on the size of the hydroponic system, you can grow a wide variety of leafy greens and herbs, like lettuce, spinach, silverbeet, chives, basil and coriander. Fruiting plants, like chilli, capsicum, eggplant, zucchini and peas are possible too. Its best to start small and once you master the basics, move onto growing bigger plants.
Many house plants can also be grown in hydroponics. It can be serious work converting all your house plants to hydroponics, so weigh up the pros and cons to see if it’s the best option for you.
We’ve got all the propagation equipment you’ll need to get the job done.
Photo Credit: Cath Muscat