Water Hazards: The Downside of Over or Under Watering
By Alan Ray 18 February 2022
“Water is the driving force of all nature”
-Leonardo da Vinci
Did You Know?
Two-thirds of the Earth is covered in water and of that, 97 per cent is saline based (ocean waters) leaving only around three per cent of fresh water in the world.
Remarkably, of that three per cent, 68 per cent is locked up in glaciers, snow-caps, and frozen tundra, leaving less than one per cent potable water.
Every living thing depends on water for its survival. The irony, however, is most life is composed of water. In humans, water comprises about 55-65 per cent of our physical body. Botanical life, such as plants, are made up of a mind-drowning 90-95 per cent water. That stat almost makes you wonder why you have to water them at all. But unless you’re growing tumbleweeds, you do.
Naturally, the type of plant you are growing dictates its water requirements in general, as some plants demand more while others require less. Annuals like impatiens versus cacti are an example of two types with opposite water needs. There is a balance to be struck regardless of the plant you are growing.
Under-watering a plant is not good but often, a seemingly dead plant can be brought back with a good soaking. But over-water them and your Garden of Eden can quickly become the new Atlantis, sinking beneath the waves, never to be seen again.
At the Root of it All
The roots of the plant serve several critical functions necessary for the plant’s survival. Roots are the mechanism that allows for the uptake of water and nutrients as well as providing a ground-securing anchor for the plant. They also act as a storage facility by stockpiling food for the plant to consume when nutrients may be scarce or depleted.
When it comes to roots, plants are typically divided into two groups: tap root or fibrous. The fibrous variety, known botanically as dicots (dicotyledon), include grasses, roses, pansies, sunflowers, and about 200,000 other plants. Dicots’ roots tend to grow closer to the surface than a solo tap root. The fibrous root system of a Dicot is very effective at taking in food and water while helping hold the plant to the ground. Cannabis plants are dicots.
The other root system belongs to plants with a signature or single tap root. Essentially, they have one main root with many flanking roots growing from that. Plants with this root system are classified as monocots (monocotyledon). Root vegetables like parsnips and turnips as well as carrots and others fall into that category by virtue of their thick taproot. This larger root allows the plant to burrow deeper into the earth and store larger amounts of food to be used when nutrients in the soil are low. It also serves as a strong anchor.
The effects of under-watering a plant become obvious with time. First drooping, then yellowing leaves that wither and begin dropping off. Soil that begins to crack and split until it subsequently hardens. Over time the roots will shrivel up while being squeezed by the ever-compressing dirt as its moisture content wanes, losing their root’s ability to transport food and water if there was any. Pretty simple. No water and eventually the roots dry up and die, taking the plant with them.
Plants are quite resilient though and sometimes a good drink is enough to bring them back from a moribund state. A tumbleweed can blow around the desert for nearly a hundred years without water (true) and should it get blown into a puddle or get rained on, can begin to grow again.
For the most part, we know what roots do and how they function. I won’t bore you with all the Latin names. Over-watering is under-watering’s evil twin, who, in the end, delivers the same result: the eventual death of the plant. Thankfully, this tragedy can be avoided with just a little common sense and a moisture meter. Moisture meters work great and will tell you exactly when your plants need watering. It’s nearly foolproof.
Indoor gardeners particularly, and inexperienced growers especially, are most likely to over water their plants. Experience is a marvelous teacher, and should you lose some precious plant due to too much water, you probably won’t make that mistake again.
That said, it is an interesting dichotomy that over-watering can mimic the effects of under-watering. Here’s how. Oddly enough, plants that receive too much water can show symptoms similar to those suffering from not enough. Stunted growth, sagging branches and drooping leaves. Over watering can also flush out any nutrients you may have given the plant, thus, starving it as well.
The mistake is made when the top part of the soil feels dry, giving the impression the rest of the soil must need water. Beginners are fearful their garden may suffer if they don't keep their grow medium wet and, hence, tend to over water. Good drainage is paramount to avoid over saturation.
Too much water is the main cause of root rot and other problems like mold. When the roots are gone so is the plant. The result of over-watering is a strange dichotomy. The drowning of the roots prevents the uptake of water so the plant succumbs from lack of water. It’s kind of like dying of thirst while you’re drowning.
I strongly encourage the purchase of a moisture meter. Many times I felt as though I should water, only to discover (by using the meter) it wasn’t yet time.
The Good News
Plants are survivors and very adaptable. Over-watering doesn’t always result in the plant’s demise. They are capable of overcoming any number of adverse conditions to include drought, flooding, and temperature fluctuation. The beauty of growing indoors is your plants are subjected only to the conditions you create.
Be your own weatherman and create an environment in which your favorite plants will not only survive but thrive.