Why do my plants die from over-watering, but can live in water?

General Care

Do you face the same dilemma? In Singapore, we don’t like to grow plants in water due to outrage of dengue cases every now and then. Soil is much preferred for any gardeners. However, why does it start to witter once it is potted in soil?

The explanation is simple – oxygen and microorganisms present in soil. Oxygen is crucial for root growth. It’s easier for roots to get oxygen in water than in waterlogged soil and to perform gas exchange (take oxygen and release carbon dioxide).⠀

There is a lot of competition for the oxygen in soil. Besides the plant’s roots, different microorganisms use it. As the supply of oxygen reduces, anaerobic bacteria and fungi start to develop in the absence of oxygen. Since there is a lot of water, especially if there isn’t a lot of light, plants are not able to use the excess water, and once anaerobic bacteria and fungi start developing, they cause root rot.⠀

Water usually doesn’t contain as many microbes as soil, so there is less competition for oxygen. Also the oxygen is easily available and plants can conduct gas exchange and grow.⠀

Soil also compacts over time, which leads to reduction of space for oxygen. This is why you need to repot your plants every 1-2 years. You need to completely replace the soil, with fresh, well draining mix. Once you completely replace the old soil with fresh, new soil, you provide a new dose of oxygen to plant roots.⠀

To learn more gardening tips, you could visit mr. houseplant guru FB page for more information. https://www.facebook.com/mrhouseplant/