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Soil Turning Green: Here’s why and What you can do

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Soil turning green might not seem like a big problem, but it can cause things to go bad really fast if not addressed.

Soil will turn green because of the growth of algae on the plants. Algae grows in moist, humid, and wet climates. The presence of excessive water in the soil is the main reason behind the growth of algae. Thus, excessively wet plants and soil promote algae development, turning the soil green.

Want to know more about the growth of algae on soil? Are you looking for ways through which you can prevent it?

This article will explain, why soil turns green, the negative effects caused by it, and what you can do to fix it.

Why Does Garden or Potting Soil Turn Green?

Moss on top of potted plant soil

Water is the leading cause behind the garden or potting soil turning green. Algae will grow in wet, moist, and humid climates. Hence, for all the reasons stated below, excessive water in the soil is the leading cause, despite having it in excess quantity in different ways. 

The first reason the garden or potting soil turns green is that the soil has been overwatered. The water causes iron in the soil to oxidize, which turns the soil green. Over-watered soil and high exposure to the sun promote the growth of the green layer, i.e., algae. 

Excess water invites the growth of algae or moss. Algae and algal spores can grow in soil, water, or even air. So, clean soil won’t prevent it from turning green. Maintaining a water balance in the soil is essential to avoid turning it green.

Bottom watering plants can help overcome the problem of overwatering and we have written a detailed article on bottom watering based on our experience and how it prevents a lot of soil-related problems.

If the garden’s draining power is poor, it is more likely that the soil will be wet. And you know, excessive water in soil invites the growth of algae. 

To test the moisture and pH of the soil you can use the cost-effective Trazon Soil 3-in-1 Meter. It not only tests for pH but also moisture content and light intensity. You can find it by clicking here!

Trazon Soil pH Meter 3-in-1 Soil Tester Moisture

Is Algae Bad for Plants?

Algae are not bad for plants; they are the primary food source for many aquatic animals. Algae can be found in many ecosystems and play a vital role in the food chain. 

It also provides shelter for many species of marine plants and animals. It also helps absorb carbon dioxide from the atmosphere, which helps regulate the climate.

Algae are known to be highly beneficial to the environment because it provides food for fish, other aquatic animals, and birds. However, despite being a good food source for many tiny organisms, it can also prove harmful to plants.

When it grows excessively, it may cause potential problems for plants in ponds and lakes.

Algae can block sunlight from reaching underwater plants, disrupting photosynthesis and leading to an oxygen shortage in the water.

It can also produce toxins that are harmful to aquatic life. These toxins may accumulate in fish that eat algae or other organisms that feed on algae like zooplankton and tiny crustaceans called copepods.

Also, algae compete with plants for resources such as light and nutrients. It grows on the surface of plants and prevents them from receiving enough sunlight from the sun. 

This prevents photosynthesis, so the plant cannot produce energy. Hence, in this situation, algae are not suitable for plants; otherwise, if it is in small amounts on the plant, there is no issue. 

Are Algae Safe for Seedlings?

Algae is a type of plant, but it’s dangerous to seedlings. It’s harmful to the plant’s roots, and it will stop them from absorbing water. It should never be added to a pot of soil for a seedling.

Hence, algae are also not safe for seedlings because they can cause them to die.

It needs a lot of water and nutrients; if there isn’t enough, the algae will take what it needs from the surrounding plants. If too many algae exist, the water will become toxic to plants.

Will Algae Deplete Nutrients From the soil?

Algae are a type of plant that requires a few essentials to grow: 

Nitrogen Nutrient

It is not likely that the algae will deplete all the nutrients from the soil. The most common nutrient that algae require is nitrogen. If there is an excess of nitrogen in the soil, then it will promote algae growth and may eventually lead to some nutrient depletion.

Therefore, whether algae can deplete soil nutrients depends on the quantity of nitrogen and phosphorus.

When algae grow on soil, they will take up the nitrates, ammonia, and phosphates that are present in the water, and these nutrients are not available to other plants. This can lead to an imbalance in the nitrogen cycle.

The growth of algae also reduces the amount of oxygen in the water because it cannot absorb as much oxygen as other aquatic life forms. This will make it difficult for fish or other marine animals to survive.

Hence, to conclude, we can say that if the quantity of nitrogen and phosphorus as nutrients is high as what is required by the plants, then algae may not prove to be as harmful to the plants as it will consume the extra nutrients and balance the number of nutrients in the soil. 

If the amount of nutrients in the soil is balanced or is less, then algae may threaten the life of plants, as it will cause the lack of nutrients like nitrogen and phosphorus in the soil as required by the algae. 

I use this Miracle-Gro Potting Mix from amazon, which ensures my plants stay healthy long after repotting. You can find it by clicking here.

This specially formulated blend of potting soil is designed to give your plants the perfect balance of nutrients, moisture, and aeration for vibrant plant growth.

miracle grow indoor potting mix 2 pack

How To Safely Get Rid Of Algae

Algae are plant life that can grow in freshwater. It is not always easy to get rid of algae. There are many ways to do this

Some of the most valuable methods to safely get rid of algae are: 

Using Chemical Treatment

Building up algae on the surface of your pond or lake can lead to an unpleasant smell, unattractive appearance, and reduced oxygen levels. 

The easiest way to get rid of algae is by using a chemical treatment like algaecide. This treatment will kill any algae that you have present in your pond. You can also use various chemicals to get rid of algae. 

Expose the Potting Soil to Sunlight

Algae can be a significant problem in a garden. It can make the soil slimy and slippery, harming the roots of plants.

There are many ways to get rid of algae, but the best way is to expose it to sunlight. This will cause drying out the soil, which will make it difficult for the algae to grow and thrive.

It is important to remember that this will not work if you have a pond or pool with algae because they need water and sunlight for photosynthesis.

Getting Rid of Algae Manually

You can get rid of algae by using a chemical treatment, but this is not safe for everyone. It is also expensive and time-consuming. 

You can use a pressure washer, but this will damage your surface if you use it too much or incorrectly.

You should also avoid using an abrasive scrubber because it will cause the algae to spread instead of going away. 

Prevent Algae Growth By Bottom Watering

Bottom watering is applying water to plants from the bottom up. The flow of water is opposite to the conventional watering method and is pulled up into and throughout the soil by capillary movement. 

This prevents the top layer of soil from remaining wet for too long which can promote the growth of algae.

The bottom watering process

The best way to get rid of algae is by getting rid of it manually.

There are some steps that you need to take before you start the process. These steps will help make the process easier for you so that you don’t struggle with it too much.

Step 1: First, get a pool brush and scrubber. 

Step 2: You’ll also need a bucket because sometimes algae will get on your hands while you’re cleaning the pool, and then they’ll end up on your skin which is not suitable for your health or the health of anyone else who comes into contact with it. 

Step 3: Use the pool brush and scrubber to rub those algae. You will notice it diminishes as you rub. 

Step 4: After this, clean the area well. Keep in mind to take care of the plant in the future so that algae doesn’t grow. 

You have successfully cleaned algae manually. It’s that easy. 

How to Prevent Soil from Turning Green

Soil can turn green for several reasons, such as the presence of iron, manganese, and copper. If you want to prevent the soil from turning green, it is advisable not to use these elements in your garden.

The easiest way to prevent soil from turning green is to add organic matter, such as compost. However, if the soil is already turning green, you can use a copper sulfate chemical. This will help kill the algae in the soil and prevent it from growing again.

Nitrogen Nutrient

Maintaining a good balance between nitrogen and potassium in the soil is also essential. This will help prevent the growth of algae and other plants that may cause the soil to turn green.

Mulching is another way of preventing soil from turning lime green. This will help reduce moisture evaporation and, therefore, the chances of bacteria growing on moist surfaces, which can cause the soil to turn lime green.  

If you want to use this technique, then make sure that you regularly remove the sand layer and replace it with fresh sand so that it doesn’t turn into a breeding ground for bacteria and fungus.

Many people use lime, which can be mixed with water and spread on the soil. Lime not only prevents algae formation but also helps reduce acidity in the soil.

Another way is by using a weed control product that will kill any weeds that have already grown from the soil. Also, you can add more nitrogen-rich fertilizer to help promote plant growth instead of weeds or algae.

Benefits of Having Algae on Soil

Algae is a type of aquatic plant that grows in water. It is one of the world’s fastest-growing plants.

It has many benefits for the soil. It provides nutrients, helps decompose dead plants and animals, and improves the soil quality.

It can also be used as a biofuel to create food and protect soil from erosion. Algae helps purify water by removing excess nutrients that other plants require. It also helps reduce carbon dioxide levels in the atmosphere by sequestering carbon dioxide from the air into its cells.

Algae can be used as an additive for soil, improving its condition and providing benefits to crops. It has been used as a natural soil conditioner for a long time. It is considered a sustainable and eco-friendly alternative to chemical fertilizers. 

Because of this, they can also be cultivated in wastewater treatment plants. Algae also produce oxygen, which helps with the overall health of the soil and plants.

Algae is a living organism that can be used to help the soil retain moisture and protect it from erosion. Algae can trap water, which helps in retaining it for plants. It also absorbs nutrients from the air and releases oxygen into the atmosphere. 

The presence of algae in the soil can also reduce the risk of erosion by binding soil particles with its strong cell walls.

Soil with algae has a higher water retention capacity and levels of organic matter, leading to better crop yields. It also increases the amount of nitrogen available for plants, resulting in more robust plant growth and reduced fertilizer requirements. 

The Takeaway

Therefore, by reading the entire article, the reason soil turns green is the algae growth. Algae are a green-colored substance that grows in moist and humid environments. 

Although algae are not harmful to the existence of plants, one should always try to avoid its growth, as algae in excessive quantities can cause depletion of nutrients in the soil, damaging the soil and the plant.

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