Everyone’s got a Secret Garden somewhere in the little corner of their home. Gardening has opened up new horizons for those who want to put their green fingers to good use. Starting this month, SJ Echo will be featuring useful tips on Plants & Gardens for you. You can also follow our Facebook Group: SJGardens and share your photos and stories.
By Christopher Teh Boon Sung, Fac. of Agriculture, Uni. Putra Malaysia, Serdang ([email protected])
How much water do our plants need? This, of course, depends on the type of plant. Air plants (Tillandsias) and cactus, for instance, require much less water than most, but generally, plants require about 5 liters of water per square meter ground area per day (or about half a liter of water per day for a pot size 30 centimeters wide). But on very hot and prolonged dry days, this amount of water can double that of normal.
Do not underestimate the importance of plant watering. Unfortunately, some gardening videos on the internet give out the wrong information. One video, for instance, teach that plants need a sort of extreme wet-and-dry cycle, where plants are only watered once the soil is very dry, and watering should be one that involves flooding the soil – until the water can be seen dripping, like fast flowing streams, out from the bottom of the pot.
This is wet-and-dry cycle kind of watering is not only wrong but can be detrimental to our plants. When we underwater our plants, they suffer water stress (that is, our plants become “thirsty”), and water stress causes our plants to wilt or fail to flower or fruit. Overwatering, on the other hand, can cause the exact same visual symptoms of that due to underwatering. Why? When we overwater our plants, the soil can contain too much water, drowning the plant roots, risking plant roots decay, and ultimately, death. So, although the plants are surrounded by water, the plants will still wilt because their roots have decayed and become non-functioning to take up water from the soil.
But overwatering also causes another serious condition: nutrient leaching losses. Leaching is the washing away of nutrients from the soil due to excess water, whether by heavy rainfall or overwatering. This means the nutrients in the soil and that added from our fertilizers are easily washed away from the soil and lost to the plants. This problem is compounded when soils in Malaysia have generally weak retention of nutrients. One reason for this is our soils are inherently low in organic matter, a kind of “glue” that holds nutrients. Consequently, it is essential we add organic matter (such as from composts or garden wastes) to our soils to increase our soils’ capability to hold onto nutrients.
Lastly, when should we water? Contrary to common perception, watering during hot days will not kill the plants – but could cause large water loss by evaporation. In other words, we waste water when we water during the afternoon and instead better to water our plants during cooler periods like in the early mornings or evenings.
Everyone’s got a Secret Garden somewhere in the little corner of their home. Gardening has opened up new horizons for those who want to put their green fingers to good use. Starting this month, SJ Echo will be featuring useful tips on Plants & Gardens for you. You can also follow our Facebook Group: SJGardens and share your photos and stories.