Can You Overwater from Bottom Watering: What you should know


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Bottom watering takes the uncertainty of overwatering away when watering plants and can be done once the plant can be handled easily. 

Bottom watering prevents overwatering by allowing the water which was absorbed into the soil to drain freely out the soil through the same way it entered. 

Overwatering and it’s accompanying effects can be easily avoided by understanding how bottom watering works and how it can be used to prevent overwatering. Read on as we explain!

Understanding What is Overwatering

wet potting soil

Overwatering is a common problem encountered when watering plants. 

Overwatering is caused by applying more than the required amount of water to soil when watering plants leaving the soil damp and wet. 

The water stays in the soil long enough to deprive the roots of oxygen causing it to stifle and cause root rot.

Improper drainage, compacted soil and soils high in clay can increase the likelihood of overwatering. 

Applying water to plants can be a tricky business and in a lot of cases too much water is added to the soil. 

Bottom watering can actively prevent overwatering by allowing only the required amount of water to be held within the soil. 

Important Note: 

Watering plants by the bottom watering method will only work with a well draining potting mix. 

If the soil is compacted or contains too many clay particles then the water which is absorbed into the soil will be held longer than it should. 

Interested in bottom watering trays? I have found durable trays which worked well for all my plants. You can click here to see them on amazon.

10 Plant Growing Trays

How Bottom Watering Works

Bottom watering is the act of placing a plant in a pot with drainage holes into a tray with water for a period of time which allows the water to move up into the soil through capillary motion.

The capillary motion mentioned above is facilitated by tiny spaces within the soil. 

It is defined as the movement of water within the spaces of a porous material due to the forces of adhesion, cohesion, and surface tension.

The water grabs onto the sides of soil particles and also onto other water molecules in a pulling motion until the entire mass of soil is wet with water. 

Bottom watering plants infographic

How Bottom Watering prevents Overwatering

Bottom watering is an alternative method of watering plants which actively prevents overwatering. 

This is achieved by the weight of the water draining freely after the plant is removed from the watering tray. 

Let’s get into why this happens. 

As the water is applied from the bottom it moves up into the soil via capillary motion.

The water in the bottom watering tray tends to support the water that moves up into the soil. 

When the plant is removed from the tray, the water is no longer supported and drains freely from the soil. 

What this does is rid the air spaces within the soil of water as it drains out. 

The symphonic effect of the draining water then pulls fresh air into the air spaces within the soil that was previously filled with water. 

This provides the plant roots with fresh oxygenated air as well as a moist surrounding from the water that was actually absorbed into the soil particles themselves. (Not the air spaces)

What are the effects of Overwatering

Overwatering can lead to problems such as:

  • Root rot 
  • Gnat infestation 
  • Wet soil covered with algae 
  • Stunted plant growth

Root rot – 

is a houseplant disease that’s usually caused by a bacterial or fungal infection. 

Gnat infestation –

Gnats are a type of fruit fly that are attracted to the moisture of potting soil, adult gnats lay their eggs on organic matter within the first two centimeters in the soil. 

Wet soil covered with algae –

Whenever the soil is moist it can cause the spores of algae to sprout out creating a green carpet effect, covering the surface of the soil. 

Stunted plant growth –

As a secondary effect of damaged roots from rot, the plant’s growth will start to become somewhat stunted. 

This is because of the roots’ ability to absorb the required amount of moisture and minerals from the soil to maintain the plant in a healthy state. 

What if you forget the Plant in the Tray

Forgetting the plant in the tray is a possibility when bottom watering.  But have no fear, as long as the plant is not left there for more than a couple hours. 

Bottom watering plants usually takes anywhere between 15 to 30 mins. 

However if the plant is forgotten of a longer period of time not exceeding 6 hours, you’ll be fine. 

After removal, the excess water will just drain out of the pot. 

Here is where you will have to place the plant into a saucer or on top of a sink to prevent making a mess. 

Additionally, the same bottom watering tray can be used as a holding container for the excess water to drain out. 

JayLea

JayLea has a passion for plants and has been gardening since 2015. He has valuable knowledge about gardening and houseplant care and can answer everyday practical questions that every plant owner has.

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