Grow your plants without soil

For so long, we have struggled to look for the right soil to grow our plants. We have even gone as far as making compost pits to ensure we get nutritious soils for our plants. But how about if you were told that soil is not all there is to healthy plants? How about that water is just good enough a medium for your plants to grow? The growing of plants without soil is known as hydroponics and Simon Ogwal, a commercial producer of select crops, agrees that plants can grow minus soil.

“However, they cannot grow without what soil offers them. These include nutrients, support, supply of oxygen at the roots, not forgetting the protection from extreme temperatures,” Ogwal says, however, that these can be provided to the plant devoid of soil. For example, plants need nitrogen potassium and phosphorus and trace elements such as copper, zinc, cobalt which are found in the soil in small amounts. “You can buy a product called NPK to help you get some of these nutrients and add them to water.”

Nutrients
Hellen Makika, an agronomist, says different formulations of NPK are needed depending on the stage the plant is at. For example, when plants are still very young, 20 litres of water will take 50g of NPK. “If planting them individually, you can distribute this mixture into the various jars you are using. When the plants get bigger, they will need more, you will then increase the grammes of NPK to 100,” she explains.
Makika adds that when the plants are bigger, they will also need the trace elements. “As the name suggests, they are needed in small quantities. Therefore, start with 5g, then when they are flowering, incase you are growing vegetables, increase it to 7g and 10g when fruiting in 20 litres of water,” she shares.

When flowering, Makika says the plants will also need magnesium which can be found in magnesium nitrate. “They will also need calcium from calcium nitrate and more potassium when they start fruiting.”
That said, she says if what you are into is simply ornamental plants, then NPK is sufficient for their growth. She adds that seeing that NPK is added after being mixed with water, you do not need to put any more water. “You can add this fertiliser solution when the levels reduce.”

These fertilisers and the trace nutrients can be got from Container Village and a kilo of NPK is at Shs8000, retail price, zinc sulphate is approximately Shs135,000 per 25kgs, copper sulphate is approximately Shs450,000 per 25kg.
Ogwal says all plants need an acidic environment to thrive. “To maintain this environment, you need to add some acid to the water. You can use hydrochloride acid and concentrated sulphuric acid. For example, 5ml of concentrated sulphuric acid mixed in 20 litres will give you a pH of 5.5 to 5.8,” he explains. When working with acid, ensure there are no children around and you are careful not to spill any on your face. For safety measures, wear gloves so that if any should splash on your hands, the gloves will avoid any harm happening to you.

However, each plant thrives in a different pH. Therefore, you will need a pH metre to see if you have acquired the right acidity for your plants. “Without a proper pH balance and the proper trace minerals (varies based on the plants grown); the plants will be unable to adequately take in water or nutrients.”
According to gardenersnet.com, spider plant’s pH is 6.1-6.5, bamboo’s pH is 5-7.5. “Find out the right pH for your plants to enable them grow well,” Ogwal says. PH metres can be found in shops selling laboratory equipment such as Simulacra Laboratories on Bombo Road at Shs450,000.
You will also need to add pebbles to the planter. “These make for healthier plants as they help with root distribution. Consequently, the plant gets more securely fastened as it would if it were in soil owing to the growth of more roots,” Ogwal shares.

Rain water
Not all water is ideal for your plants in this type of plant growing method. “Rain water is your best bet as it also gets hydrogen as it drops from the skies. Hydrogen is great for your plants’ growth. However, you may also use well or spring water seeing that it is natural hence not stripped of minerals,” Makika shares. In case all you have is tap water, you will need to let it sit for a day. “Seeing that it contains chlorine, which is detrimental to plant growth, sitting it for a day allows the chlorine concentration to reduce hence not damaging to your plants,” she elaborates.

Indoor plants that grow well in a soilless environment include snake plant, spider grass, lucky bamboo, orchids, air plants, aloevera, hycinths, marimo moss balls, lavender, coleus plant and pathos plant. If you want a vegetable garden instead, then you might go for all sorts of herbs such as basil, chives, lemon balm, mint, oregano, rosemary, sage, stevia, and thyme, tomatoes, lettuce, cucumber, and strawberries. “They must be light plants so that they can easily float. Therefore, heavy vegetables such as cabbages cannot grow in this environment,” Ogwal advises.

While it may seem unnatural for plants to grow without soil, it is considered the best way. That is because plants will not die due to lack of water as many people easily forget to water plants. More to that, you are guaranteed of less diseases, less pests as these are carried mainly by soil. In the end, you will have faster growth and more yields for those growing vegetables and a better look for those growing ornamental plants.