The Problem of Aeration in Houseplants
It’s no secret that plants need water in order to grow: it’s one of the four essential elements of life, along with air, nutrients, and sunlight. A problem with too much moisture on plant soil is that it blocks off one of its essential ingredients: air. It is similar to drowning a plant’s roots.
Although plants can survive an occasional over-watering, if you repeatedly over-water, there is no way for oxygen to enter the soil for the roots to absorb it. Plants need loose, well-aerated soil to thrive.
Photosynthesis and respiration are the two most important biological processes in plants. Photosynthesis occurs in the green tissues of plants and involves the conversion of light energy and carbon dioxide to sugars. These sugars are used to produce energy and water, along with carbon dioxide, and oxygen, in the body through respiration.
If the roots of plants cannot absorb oxygen, they will not be able to complete one of the most vital processes that keep them alive. Thus, it is so important to ensure the soil is aerated properly and that overwatering plants can be detrimental to their health.
The Dangers Of Poorly Aerated Or Soggy Roots
When roots for too long are left in inadequately aerated or overwatered soil, they are at risk of dying:
- Air cannot be taken in by roots and delivered to the plant.
- In the absence of strong roots, fungi and bacteria can invade the plant.
As the organisms attack the roots, damage and destruction are caused, eventually leading to the plant’s ruin if not promptly treated.
How To Aerate Soil In Potted Plants
It’s pretty easy to get air to circulate through the soil. How you approach aeration depends on the health of the plant and when you aerate.
Potting A New Plant
Even on day one, if you are just potting a new plant or cutting, there are things you can do to ensure your plant has a healthy start.
Plants require a special kind of soil, so you shouldn’t simply use any old soil or dig up concrete or dirt from the yard. The soil you use for your plant should provide draining, air circulation, moisture retention, and nutrient content. It should also be tailored specifically for that type of plant.
In your potting mix, you can include many different types of materials for aeration and drainage. These materials will improve the aeration and drainage of soil and also help to maintain moisture.
Common Additives To Aerate Soil In Potted Plants
Perlite. Perlite is a light and airy volcanic rock that improves drainage and aeration. Wood chips are sometimes substituted for perlite in inexpensive potting mixes. They act more as a filler than an aerator.
Coarse sand. Sand particles expand under pressure and break up dense soils, improving drainage.
Vermiculite. This mineral is produced by heating mica chips. It helps aerate the soil, while retaining moisture and minerals that can be released gradually as the plants require them. Ideal for plants with high water requirements.
Peat moss. Decomposed plants and mosses that are used to make potting soil. They can hold a lot of moisture and release it when needed, while remaining lightweight and providing reasonable aeration.
Sphagnum moss. Typically used in hanging plants that lose moisture quickly (but cannot be overwatered) to improve soil moisture retention and aeration. Bog moss is commonly dried and used to improve soil aeration and moisture retention.
If you want to grow healthy plants, you need to use soil that delivers nutrients and supports root growth. Make sure your soil recipe is loose enough for roots to breathe and contains materials to hold and release water when needed.
A good basic potting soil recipe that I often use is;
- 1 part peat moss
- 1 part perlite
- 1 part good quality topsoil
Making Sure Your Pot Has Airflow
If you have good potting soil, then you need to make sure your container or pot is going to cooperate by providing airflow. Aeration is reduced significantly if you use the best soil you can find, but your pot prevents air from entering while allowing water to exit.
Depending on the kind of pot you have, the aeration process may differ.
Because clay is porous, clay pots provide natural aeration of the soil, increasing airflow to the roots. This is possible because air and water move freely through the walls of the pot.
Clay’s porous properties are also conducive to water loss from the pot, increasing watering needs of your plant. This is especially helpful for plants that dislike sitting in wet potting soil for a long time.
As opposed to clay pots, plastic containers are neither porous nor breathable. Therefore, they hold in moisture and prevent air exchange. While the advantage of plastic pots may be that they require less watering, they also dramatically reduce aeration. Watering must be monitored much more carefully.
Create a few small holes around the pot with a nail or drill using a small bit. They should not be large enough to fall out, but large enough that excess water can drain out and air can get into the soil.
Decorative Metal and Ceramic Pots
It is not possible to increase the porousness of these pots or their airflow. If the container is large enough one solution would be to double pot a plant:
- In the bottom of the decorative pot, place rocks or stones.
- Make sure that the inner pot of your plant is slightly smaller than the decorative outer pot. It should have drainage holes.
You can enjoy the aesthetics of the decorative pot by placing the inner pot on top of the stones. This ensures water will drain and air will circulate to the potted plants.
The technique I use with many of my indoor plants is a favorite of mine. I also enjoy using beautiful decorative pots, which add to the beauty of my home and the plants.
How To Aerate Soil In Potted Plants With Chopsticks
If your plant has already been potted, you might be able to aerate the soil by using chopsticks, a stirrer or a sturdy straw. With the help of this handy gadget, you can gently loosen dirt around the roots, as well as poke holes in the soil near them.
The roots of your plant will have improved airflow if you do this in healthy, dry soil before watering them, which reduces the danger of waterlogging.
Aerating A Potted Plant That is Already Overwatered
During the early stages of potting, building in some aeration is pretty straightforward, but that’s not the case when you notice a plant that is already suffering from inadequate aeration or overwatering.
You need to determine how long the plant has been suffering and how severe the symptoms are:
Signs Your Plant Is Overwatered
Wilted or yellowed leaves. The soil on a plant that appears weak and sallow but is moist to the touch indicates it had too much water and root rot might have set in.
Little blisters on leaves. Blisters on your plant are actually edema, an indication that it is absorbing more water than it uses.
Brown leaves. Brown leaves can lead you to wonder if you are watering your garden too much or too little. You can find out by sticking your finger in the soil. It may be that the soil requires some water if it is dry beneath the top layer. However, if it is wet, browning may be an indication of too much water.
Rotten smell. There may be bacteria or fungi living in your plants’ soil causing an unpleasant odor. They take advantage of the roots that are too weak to defend themselves. Infected roots may be the result of root rot if they have been left untreated for a long time.
Aerate Soil In Potted Plants To Revive Them
The vast majority of overwatering can be remedied. However, root rot in the soil may make it impossible to restore.
It may be enough to refrain from watering for a few days and lightly aerate the soil with your finger or a chopstick if your plant doesn’t smell and its leaves are just slightly wilted.
Repotting a Plant in Soaked Soil
The presence of wilted leaves and an unpleasant odor may indicate that your plant is drowning in its own soil, which indicates it is time to repot it.
If the soil smells rotten, it is not recommended to reuse it. That odor indicates that bacteria or fungi are alive and well in the dirt, and the same problem may recur if you use it again.
The pot should first be washed if you will reuse it:
- Take the plant out of the pot.
- Remove all the potting soil by gently shaking it.
- Remove any excess moisture by rinsing and patting the roots.
- While you prepare the plant’s new home, place the plant in an empty garbage bag while you keep it safe.
- After cleaning the pot with a mild bleach solution, rinse well with water, then fill it with new soil: a fluffy, nutrient-rich soil with plenty of air holes.
- Remove any roots that appear damaged and gently trim the plant’s roots. Carefully place the plant in its new pot and water it well. Water very carefully in the days that follow.
- Make sure not to water on a time schedule! Water when the soil feels dry enough, depending on the water requirements of the plant.
Plants usually recover within a few weeks. In some cases, it might take them longer, but they recover in most cases. Your potted plants will live a happier and longer life if their soil is properly aerated and provided with proper drainage.