The Basics of Plant Watering
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Plants need water, that is a well known fact, however, proper plant watering is not as straightforward as it may seem. While no plant will survive without ever getting water, many plants will suffer a similar fate from being overwatered. There are many factors that go into how to correctly water plants and each plays an important part in making sure your plant stays hydrated and heathy.
Plants also require certain atmospheric conditions to be able to respire and uptake nutrients effectively, if there is an imbalance in these conditions the plants will not be as efficient at carrying out these processes. An imbalance such as this is related to a phenomenon known as Vapor Pressure Deficit. This is a crucial topic to understand when growing plants and is a topic we’ll be covering in more detail in a subsequent article.
Proper Plant Watering, An Essential Technique
Many products are available to help make watering your plants more precise and simplified and, while this is great, it helps to know the fundamentals of plants and their water needs. There is a large range of water needs and the differences are determined by where plants come from. As plants are sessile (they don’t move once established) and travel only when and if their seeds get dispersed, they have evolved to life in very specific environments.
The environment a plant lives in, also referred to as the biome a plant lives in, determines almost everything about that’s plant’s ability to survive. For some plants like the Himalayan blackberry (Rubus [roo-bus] armeniacus [are-men-e-ack-us]), the location where the plant is growing is less important as they can tolerate a wide range of environments. These species are an exception however, most species are specific to certain environmental conditions.
To be safe, it’s always best to know where your plant is native to or, at the very least, the most effective watering schedule for the plant.
How To Increase Humidity and Keep It Stable for Your Plants
Many indoor plant species prefer higher humidity than most houses likely have. If your house is air conditioned or you constantly run a dehumidifier, this reduction in humidity can have a negative impact on your indoor plants. Most plants will do OK with normal humidity levels; however, tropical plants prefer very high humidity. These plants will benefit greatly from some added moisture in the air.
Tropical plants such as this [species] are native to regions with high humidity, replicating that will help it maintain its health and vigor.
Seeds and seedlings are another group of plants that will benefit greatly from increased humidity. Seeds in general need higher moisture levels to aid in germination and help their delicate roots grow strong. Maintaining high humidity for seedlings is safer than frequent watering as it can help reduce the susceptibility of fungal outbreaks.
Plant cuttings also need very high humidity while working to establish roots for themselves. Plant cuttings that do not have high enough humidity will almost never be able to produce roots and will wither and die.
There are several ways in which you can increase humidity for your plants. The options range from whole room humidifiers to smaller options for individual plants enabling you to choose the best option for your home and your plants. Plants benefit most from stable humidity levels. Once you have increased humidity for your plants, do your best to keep the humidity as stable as possible.
Natural Humidity from Plant Communities
Plants need to take in water to grow and be healthy but they also expel water from openings in their leaves known as stomata. In doing this, plants essentially create a micro-environment around themselves. If you’ve ever been to a thick forest, this is one of the reasons there is a noticeable difference between air inside and outside the forest.
A single plant by itself is only going to have a minor impact on the humidity levels around itself; however, having multiple plants arranged together will have a greater impact. Keeping many plants together in close proximity makes a sort of microclimate around the plants, essentially forming a community regulated micro-climate! Each plant contributes to the humidity levels for the whole group.
If you have several plants, keeping them close together will help them establish humidity levels that are beneficial for all the plants involved. This is not a cure-all solution by any means but it can help you regulate humidity for your plants better.
Whole Room Humidifiers
Another option for increasing humidity for your plants is to use a whole room humidifier. There are several options available on the market (we’ve included our favorites below) and the “right” humidifier will come down more to preference and goals rather than specific brands. When it comes to humidifiers, the most beneficial for plants are the misting types.
A whole room humidifier like this Levoit humidifier is ideal for increasing the humidity in a medium sized room.
Misting humidifiers increase humidity, unsurprisingly, by emitting a gentle mist that gradually increases humidity in an area. Depending on the size of the room and how closed off it is, misting humidifiers can significantly increase airborne humidity. If you have several indoor tropical plants, placing them together in a smaller room that is closed and has a misting humidifier will dramatically improve their health and happiness.
Even if you don’t want to use a misting humidifier in an enclosed room, having one next to your indoor plants will still be a significant benefit to their health!
Plant Pot/Tray Humidity Domes
If you have only a handful of plants, perhaps even one or two, and don’t want to use a misting humidifier, you can opt for a humidity dome instead.
Humidity domes are simply plastic coverings that fit over individual pots or over entire plant trays. In general, humidity domes are more useful when you’re propagating plants or if you're growing sensitive plants. The dome creates a sort of micro-climate around the pot or tray which helps keep moisture in the air. This means the soil will dry slower which is important to consider as too much moisture in a pot with a humidity dome can lead to fungal outbreaks.
A small starter tray with a form-fitting humidity dome to maintain high humidity.
When plants are first starting out from seeds, corm, bulbs, nodes, cuttings, or tissue culture, keeping the humidity both higher than usual and maintaining that humidity will help the new plants grow most optimally. It is for this reason humidity domes are ideal for these young plant life stages.
Humidity domes come in several shapes and sizes to fit a wide variety of pots and trays. Regardless of the dome you choose, it’s important to make sure the dome fits correctly on your pot or tray. A loose fitting humidity dome won’t regulate the micro-climate as well and can lead to humidity fluctuations.
Pebble Trays and Saucers
Another approach to increasing the ambient humidity around your plants is to incorporate a saucer or pebble tray into your setup. A pebble tray is simply a saucer filled with small rocks; pea pebbles, fine gravel, and river rocks are just a few ideas for good rock types to use. While saucers and pebble trays can be used to do the same job - increase ambient humidity - they have other purposes as well.
Saucers are most ideal for situations where you have a pot that has drainage holes and you need to protect whatever surface it’s sitting on. The saucer is placed under the pot and serves as a basin to catch the water that drains from the pot during watering. The collected water in the saucer will evaporate and that process will increase the humidity around the plant a bit. The amount of surface area of the water will partly determine how quickly it evaporates so it’s best to choose a saucer that is proportional to the pot size.
A pebble tray can be as simple as a saucer with gravel and water in it!
Pebble trays are more suited to increasing humidity as the pebbles help slow the process of evaporation and increase the length of time the humidity is increased. To create a suitable pebble tray, simply fill a saucer with your selected rocks and add water to the saucer, the more water you add, the longer evaporation will take. The plant pot sits atop the pebbles in the tray so it is important to take the water volume into account. You don’t want water draining from the pot to overflow the pebble tray!
A word of warning regarding saucers and pebble trays, many saucers, regardless of material, will have mildew grow on the bottoms of the saucer if there is no airflow beneath them. It is a best practice to add some sort of feet to the bottom of your saucers and pebble trays. You can also choose saucers that already have feet. Something as simple as the little adhesive domes you find under tabletops will suffice. Your main goal is simply to ensure there is space between the saucer bottom and whatever it’s sitting on.
Spray Bottles, Pressure Sprayers, and Micro-Aerosol Spray Bottles
If you’d prefer a more hands-on approach or possibly want to add another source of humidity to compliment a pebble tray, you can use spray bottles. Many tropical plants and trees are used to having mist condense on their foliage and provide increased humidity. Misting plants, either with a traditional spray bottle or a micro-aerosol spray bottle will help with water loss and can keep your plants healthier.
One of the easiest ways to water your plants is by using a pressure sprayer. Pressure sprayers are handy plant watering tools as they allow you to continuously spray water. They include pump handle that you use to pressurize the chamber and then it’s as simple as pointing the spray wand and depressing the trigger. Most pressure sprayers even have a way to lock the trigger down for continuous spraying!
VIVOSUN pressure sprayers are our favorite sprayers for watering our indoor plants. Click here to see our detailed review of these sprayers.
VIVOSUN pressure sprayers make watering multiple plants a breeze.
You’re likely very familiar with spray bottles at this point but you may never have seen or heard of a micro-aerosol spray bottle. These bottles are commonly used in the hair styling industry due to the micro-bead spray they produce but they are excellent spray bottles for plants as well. The fine mist of these bottles is light enough not to blow your plants around and can reach nooks and crannies a traditional spray bottle might miss. Another helpful feature is the continuous stream these bottles produce. As you pull the trigger repeatedly, the mist stream flows continuously.
Knowing When to Water Your Plants
Now that you have an arsenal of tools and tips to keep the humidity high for your plants, it is time to cover one of the most important aspects of watering your plants. It may seem like a simple idea - knowing when to water your plants - but there is a lot that goes into this timing and it can be, at times, anything but straightforward.
Knowing the right time to water your plants is important as it keeps them healthy and prevents them from drying out and dying.
One of the most important aspects of watering your plants is to know its natural water exposure. This means knowing how much water the plant species is usually exposed to in its natural habitat. Once again, knowing the habitat the species is native to is important for best care guidelines. You don’t want to improperly water your plant as under-watering and over-watering can both lead to very serious problems.
Under-watering can lead to drying out and loss of foliage, branches, or plant death. Over-watering can lead to root rot and subsequently plant death as well. Unfortunately, both over- and under-watering issues often present the same way, for instance, growing leaves on some species can indicate too much water or too little. For this reason it’s important to know when to water and how much to water.
Luckily, there are tools available to help you determine if your plant needs water. You can always use your finger to test the moisture level of the soil - some people prefer this method - but some prefer the aid of a moisture meter.
Moisture Meters for Plant Watering
A moisture meter is, as the name implies, a device that measures the moisture content in soils. Most moisture meters consist of a readout - digital or analog - and a metal prong meant to be inserted into the soil. Sticking the prong into the soil will give you a readout of the current moisture content in the soil. This is a helpful way to monitor how moist your plant’s soil is. Once the meter reads a low enough moisture reading (depending on the water needs of your plant), you will know it’s time to top the plant up with some water.
Some soil moisture meters come with devices that monitor other soil parameters as well such as soil pH and light exposure given the plants current location. These can be helpful to ensure your plant is located in a suitable spot and its soil is pH balanced. To be fair, most of these devices are subpar for testing pH so if you are interested in a pH meter make sure they are high quality and aren’t too cheap.
How to Properly Water Plants, Final Word
Making sure your plants have sufficient water to carry out the processes of growing new leaves and roots is one of the most important aspects of being a plant parent. Knowing how much water your plant needs based on light exposure, temperature, and humidity of your setup as well as the natural water exposure for the species are crucial for keeping your plants happy and healthy.
There are many tools and tips to ensure your plants get the moisture they need, both in the soil and in the air. Many plants can tolerate a range of water and humidity levels but constantly changing humidity and soil moisture will impact your plants’ health. Aim for trying to keep the moisture and humidity fairly constant and your plants will thank you for it.