Skip to Content

Do Plant Roots Need Oxygen – Here’s How It Affects Growth!

It isn’t too hard to figure out what most plants need. Give them the right amount of water and light; they’re usually happy campers. What about oxygen, though? Plants are known for producing oxygen but also need it to flourish. While it’s common sense not to restrict oxygen availability for stems, leaves, or flowers, most people don’t try that hard to ensure oxygen is available to the roots. It’s a valid question, though: do plant roots need oxygen?

Yes, they do! Even though roots require less airflow than the rest of the plant, oxygen is just as necessary for the roots.

Do you want to ensure that your plants get enough oxygen to their roots? Just keep reading to find out more!

Why is oxygen essential for plant roots?

In addition to photosynthesis, plants also undergo respiration. This process is performed by the entire plant, which means that even the roots need to be able to access oxygen.

Some plants need more, and others need less. For example, succulents need plenty of oxygen to their roots, so you should plant them in loose, sandy soil. On the other hand, hosts don’t need as much oxygen for their roots; they thrive in soil that holds onto moisture. 

If you were wondering why plants need the right soil to grow, this is one part of the puzzle. Soil texture and density influence oxygen availability to the roots, which you need to get right for healthy plants.

What happens if roots don’t get enough oxygen?

Oxygen isn’t just crucial so plants can “breathe”; it also plays an essential role in their ability to absorb nutrients through the root system. Without enough oxygen, the root system will eventually start absorbing fewer and fewer nutrients; this leads to plant “starvation.”

While that alone is bad news, this also makes the plant more vulnerable to pathogens. If the situation isn’t corrected in time, the plant could end up stunted or dead.

How can you tell if roots are oxygen-deprived?

If your plant is looking sickly and you suspect oxygen deprivation, here are the signs to look for:

  • Aerial roots – One clear sign that a plant’s roots aren’t getting enough oxygen is the presence of aerial roots. Since they can’t get sufficient oxygen below the surface of the dirt, they’ll try going above it to get what they need. Unfortunately, this is sometimes a trade-off for the plant; the aerial roots will get more oxygen, but the environment may not be humid enough to keep these new roots healthy.
  • Small or distorted leaves – Oxygen deprivation to the roots can result in plant stunting, and the most obvious sign of this will be leaves that are too small or oddly shaped.
  • Wilted or yellow leaves – If roots aren’t getting enough oxygen, this also hampers their ability to absorb water. This can result in drought-like symptoms such as limp or yellow leaves.

Can plant roots get too much oxygen?

When it comes to getting oxygen to your plant’s roots, they can have too much of a good thing. Excess oxygen to the roots (usually due to soil that’s too loose) can produce similar results as insufficient oxygen: plant stunting, inhibited nutrient uptake, lower water uptake, and even death if the condition progresses too far.

How do I get more oxygen to my plant roots?

Oxygen-deprived plant roots can be caused by more than one factor, so here are some things to check for before deciding on the solution:

  • Are you using the right soil? The density of your soil will determine the size of the air pockets, which are the oxygen delivery system for the roots. Potting soil represents the happy medium between dry, sandy soil and moist, water-retaining soil. Your potted plants may not do well with potting soil; you may need to mix in other types of dirt or sand.
  • Is the soil compacted? Even if you’re using the right soil type, overzealous efforts during the planting process may have resulted in dirt tamped down too tightly. It’s generally a good idea to pat the dirt down around the roots and stem when planting something, but it’s easy to accidentally pack the dirt in too tightly if you’re new to the process.
  • How much water is the plant getting? If water cannot properly drain from the soil, the air pockets will turn into water pockets, effectively preventing the roots from getting oxygen.

What about hydroponic plants?

Hydroponic plants don’t grow in soil – they’re grown in water. So how do they avoid drowning in all that water? The answer is found in dissolved oxygen (DO). Just like the other nutrients mixed into the water, DO is added to the mix to ensure that the roots get the oxygen they need.

This process is highly technical, as there are many factors influencing the effectiveness of DO. For example, water high in chlorine or salt can’t absorb as much oxygen as purer water. The same happens if there are too many bacteria in the water or even the nutrients used to feed the plants.

Can plants recover from oxygen deprivation?

That depends on how severe the problem is. In all but the most extreme cases, you can generally save the plant through steps like using more appropriate soil, loosening the soil, or changing the watering schedule.

The takeaway

If you don’t know what to watch out for, it’s easy to accidentally deprive your plants’ roots of oxygen. Fortunately, the signs aren’t difficult to spot, and the solution is usually pretty simple as long as the issue is caught early on. Roots need oxygen just as much as the rest of the plant, and with the proper knowledge about what your plants require, you can ensure they get exactly what they need.