How Often to Water Plants: The Key to Keeping Your Plants Alive

First, your plant’s leaves are dry and wilted. Now, after watering a few extra days this week, your plant’s leaves are limp and mushy. Plant health can seem like a swinging pendulum. It’s either overwatered or underwatered. How can you take control and reach a balance? How often should you water your plant?

A Few Basics on How Often to Water Plants

• Do not water immediately after bringing your plant home from a greenhouse. The rule applies if you receive your plant via mail. Let your plant acclimate to its new environment for a few days.
• Do not stick to a rigid watering schedule. Instead, monitor the moisture levels in your soil closely.

The Science Behind Watering

Water is an integral part of any plant’s system. Too much water removes the oxygen from the soil, suffocating your plant. A lack of water means there isn’t a good flow of nutrients. All plants require water: it does not matter if your plant is a rainforest-resident or a desert-dweller. 

Your plant contains cells that swell with water pressure (a process called “turgor”), making up its skeleton. For instance, think of a holiday yard inflatable. What happens when the air-flow stops? You got it. Deflation. 

Similarly, when your plant has low turgor (low pressure), it deflates. Water travels up the xylem vessels contained in the plant to the leaves. Without enough pressure from moisture in the soil, the water simply cannot travel up these vessels. 

If there is insufficient water in the plant’s soil, it will start drawing moisture from its leaves to its core, explaining why leaves and stems go limp when your plant is underwatered. The stiffness of your plant’s skeleton all depends on the water pressure!

Your plant also needs water for photosynthesis, which nourishes it. During photosynthesis, there is a process called transpiration. 

Transpiration occurs when your plant exudes moisture through its stomata (leaf’s pores) and trades it for carbon dioxide in the air, which the plant then turns into food. This process cools your plant down, and it only happens when it is receiving light. 

Put simply, transpiration takes water away from the roots and soil, putting it into the air through the leaves. That’s where you come in: you have to replace the moisture in the dirt to keep the process going. 

The Importance of Origins

Some plants can transpire their entire body weight daily, while other plants are not so swift.  You must carefully research your species of plant to determine how often you should water it. 

Consider your plant’s origin carefully. Does it come from the rainforest? The desert? Do not let your plant fool you: even some cacti come from the jungle! After you understand the region, consider your plant’s natural growing conditions. Does it grow in the treetops? The soil? Or shallow, rocky surfaces? 

Generally speaking, rainforest plants require more moisture in their soil and high levels of humidity. In contrast, some succulents only thrive when the dirt is allowed to become bone-dry.

Your Environment’s Role in How Often to Water Your Plant

Truth be told, your plant is a house-dweller. You will not be able to provide it identical conditions to its natural habitat. The environment you can provide your plant, however, plays a significant role in how often you should water. 

Humidity

If there is plenty of moisture in the air, your plant will dry out more slowly. If you have invested in a humidifier or mist your plants daily, you need to water your plants less frequently.

Light

Bright light naturally evaporates the soil’s moisture. Plants in brightly lit locations will require watering more frequently when compared to plants in low-light areas.

Air Circulation

Air currents dry out the soil more quickly. Placing your plants in the path of drafty doors, windows, or heating/cooling vents also spells disaster for maintaining a humid environment. Be prepared to water your plants more often if they are in an area with high air circulation.

Container Type

The type of pot you select for your plant also factors in how often you need to water. Terra cotta clay pots naturally wick moisture from the soil. Meaning, you will need to water more frequently. 

Other types of planters are called “water retaining” because they keep the soil’s moisture. Concrete, painted ceramic, and plastic are all examples of water retaining pots. You will need to water less often if you use one of these containers. 

Pot Size

Plants in large containers require less water in comparison to plants in smaller pots. When caring for a sizable plant, if you follow the age-old advice of “water after 1-inch of soil dries,” you will drown it. A large pot contains more soil, which means you need to allow larger pots to dry out to a lower depth.

Soil Type

Using improper soil can overwater your plant without you ever moving a finger.  Why? The dirt continues providing moisture to your plant long after you put down the watering can. 

If you use an unmodified, traditional potting mix, you will likely need to water less frequently. Remember, that’s not necessarily a good thing. Using improper soil will contribute to root and stem rot, leading to plant death. Many plant varieties require well-draining, porous soil, which dries out quickly. Take your dirt seriously!

Season

Most plants enter dormancy during the winter months, which means they require less frequent watering. Why? Your plant is not actively growing new roots, stems, and leaves. It is inactive, recharging, so it is ready to grow in the spring!

Look at the Individual

Just because you have two plants that are the same species doesn’t mean that they require the same watering frequency. Mature plants require less frequent watering, while young, rooting plants need more moisture. Even if your plants appear to be the same size, they are likely experiencing different life stages, are in different kinds of containers, a different location in your home, etc. Water these plants as individuals: only doing so when they show clear signs that they are thirsty.

Ditch the Watering Planner

Due to all of the above factors, plants do not thrive on a pre-planned watering schedule. Watering your plant weekly, biweekly, or even monthly (for some varieties) will always overwater or underwater your plant. You must listen to your plant’s ques by observing the soil’s moisture levels and watering it when it’s reached your plant’s appropriate dryness. (This “level” is based on your research around the plant’s origins and species.)

The Best Watering Method: Super Soaker

If your pot has drainage holes, you cannot overwater your plant in one sitting. The most effective method is to thoroughly soak your plant with luke-warm water until it comes pouring out the bottom. Don’t rewater again until your soil exhibits the proper signs. Frequently watering a little bit “here-and-there” will contribute to irregular watering and will easily overwater your plant. 

If you allow your plant to become chronically underwatered, don’t overcompensate. You will not do your plant any favors by watering it more frequently in hopes of boosting its health. Take steps to rehydrate the soil by bottom watering. Afterward, resume your regular watering habits. 

What if my pot doesn’t have drainage?

If you have chosen to use a container with no drainage holes, water your plant, and gently set your plant on its side. (Make sure to place it in the bathtub or on a towel.) Ten minutes later, flip your plant so that it is resting on its other side. And, after a final ten minutes, place your plant upright in its usual location. This process helps moisture soak into the roots and soil while draining out excessive water.