It’s time to weigh in on water! Plants need water to survive just as much as we do, but it’s not as simple as drinking 8 glasses per day. The amount of water needed changes based on soil composition, type of plant, age, and even time of year, so it’s no wonder watering continues to be a challenge for many home gardeners!
However, having a properly watered house plant isn’t impossible! Gaining a better understanding of how water flows into your plant and knowing your plant’s preferences is the first step in taking the guesswork out of the process. Keep reading as we break down all aspects of watering, so you can have more confidence keeping your plants hydrated!
How do plants uptake water?
The first part of overcoming overly wet or dry soil is understanding how plants uptake water. Water enters plants through their root systems. Different plants will have different looking roots, but the basic principle is the same. Delicate root hairs trap and hold water next to the roots so that it can be absorbed. The more root hairs and surface area a plant has, the easier and more efficient its water absorption will be.
The structure and the number of roots makes plants natural experts at finding water for themselves. That’s why most roots stay in the top foot of soil, on average, spreading out wide to increase surface area and maximize water uptake. Container plants work in a very similar way to in-ground plants–roots in containers tend to mold to the available space (the container they’re planted in). All you have to do is support the root system by supplying it with a consistent amount of water, and the rest is up to the roots!
How much water does my plant need?
There’s no set amount of water that plants require. I know you wanted an easy answer, but when it comes to watering, the proper amount will change depending on factors like humidity, soil, the container, time of year, type of plant, etc.
The best way to water is based on touch. Stick your finger in the pot and feel if the soil is wet or dry. If the soil is dry a few inches down, then give it water. If it’s wet, then let the soil dry out until it’s 75% dry, then water. This method works especially well if your soil is a consistent texture. Soils that aren’t mixed well or have layers of different materials may hold on to water in some areas and remain dry in others (read more about soil here).
If it seems difficult to judge the level of moisture in the soil by touch, you can use a soil moisture meter to check the moisture levels of your plants. When stuck vertically into the dirt, this helpful tool gauges moisture with a metal probe. This provides an accurate and measurable percentage of how wet or dry your soil is without even having to touch the soil with your hands.
Watering Guide By Plant Type
Because all plants are different, their watering needs will be different. Here’s a few popular house plants and their preferred moisture levels:
Plants that like moist, but not overly wet or dry soil, include Pothos, Crotons, and Ficus. Make sure there’s adequate drainage in the container to avoid over-watering, and only water these plants when the top 2 inches of soil feel dry.
Plants that can tolerate wetter soils are Alocasias and Ferns. These plants need to be watered when the top inch or so feels dry to the touch. Make sure not to leave them in standing water, and ensure your container has drainage holes.
It's important to note that newly planted varieties need deep watering once in their new location, regardless of type. The extra water will help them get established in their new environment, so give them more water than you think is needed, and let it soak in.
And of course, always refer to your plant’s requirements since water needs can vary greatly from plant to plant.
How to Water Correctly
Yes, watering a plant is simple enough, but there’s nevertheless a technique to doing it well. The golden rule of watering plants is LOW and SLOW, meaning, low pressure and a slow flow. Watering this way will provide your plant with time to uptake the water it’s being given rather than letting it drain away.
Follow the steps below to make the most out of your watering:
- Make sure the water pressure isn't too high – aim for a trickle. If you’re displacing soil, then turn the pressure down.
- Water at the base of the plant–the roots need the water, not the leaves.
- Water early in the morning (before 8 am) to avoid water sitting on the leaves, which can cause the leaves to burn in the sun, and to allow time for the water to be uptaken by the plant.
- Use room temperature water. Water that’s too hot or too cold can and will shock the roots.
- Apply enough water to fully saturate the soil. You’ll know the soil is saturated when the water starts to freely flow out of the drainage holes in the bottom of the container.
Additionally, watering accessories, like specialized pots, exist but aren't always needed. Watering globes or bottles that you fill with water and place upside down in the container can deliver too much water and an uneven amount of water to the pot. While these are good solutions to keeping your plants happy during vacation, try not to depend on them for day-to-day watering needs. Stick to a watering can so that you can control how much and how often your plants get watered.
Some plants are pickier than others when it comes to water type, but generally, this isn’t an issue, and your tap water will be just fine. If you live in an area with hard water and you use a water softener, know that this can contain excess salts–you’ll want to occasionally flush the soil with filtered water. Also, you can always collect some rainwater and use that to water indoor plants. Rainwater is preferred by plants, and it’s free to use!
Defining Watering Terms
Let's take a closer look at a few popular, water-related terms so you can better understand the watering process:
Well-Draining: This has less to do with the amount of water and more to do with the container and soil your plant is in. Well-draining soil means that it won’t soak up excess water like a sponge. Instead, water will flow through it fairly quickly. Think of sand vs. moss–sand is more well-draining than moss.
Flushing the Soil: When salts and minerals build up in the soil, you may need to flush them out in order to reduce stress on the plant. Do this by deeply watering with filtered water.
Deep Watering: This is when you fully saturate the soil and the rootball. Deep watering helps to create a strong root system. In container plants, deep watering occurs when you start to see water running freely out of the bottom of the container and all of the soil is wet.
Calcium Deposits: These look like white dust on leaves or in clay pots that appears after the water has dried. It might look like powdery mildew, but look closely to see if the appearance is more fuzzy or chalky. If it’s chalky, you have Calcium deposits. It’s harmless but can be unsightly, so try to water with filtered water and rinse off the Calcium deposits with a vinegar mixture of 1 part vinegar and 4 parts water.
Hard Water: Hard water contains lots of dissolved minerals (Mg and Ca). Tap water in some areas is considered hard, and water softeners are used to counteract the high mineral content.
Soft Water: Soft water contains very little dissolved minerals (Mg and Ca). Normal rainfall is an example of this and would be a plant’s first choice of water type.
Bottom Watering: I love this method for house plants. What this means is that instead of pouring water over the plant, you fill up the drip tray or sit the container in a basin of water and let the soil soak up the water from the bottom. This allows the plant to take the amount of water it needs without taking too much.
Watering is one of the most important pieces when it comes to caring for your plants. And getting it just right can be tricky. But as long as you’re staying in tune with your plants’ needs, sticking with a routine and following our tips above, your plants should stay happy, healthy and hydrated for seasons to come!
Your House Plant Watering Check List
- What kind of water do you have at your house - hard or soft? If you have hard water, you may see mineral deposits once the water has evaporated.
- Go around and check the moisture levels of your house plants, using your finger or a moisture meter to test the soil.
- Determine which of your plants like more or less water, and adjust your watering schedules accordingly.