Can "Air-Purifying Grass" Really Absorb Formaldehyde? Analysis of Its Air-Purifying Effect

In recent years, more and more people have started growing green plants at home. There is a green plant called "Air-Purifying Grass" (Xidu Cao) that has been heavily hyped by merchants. Legend has it that this green plant can effectively absorb formaldehyde in the home, and some claim it can even absorb radiation. So is this Air-Purifying Grass really that magical? Below, QinNong Net gives you a detailed introduction to Air-Purifying Grass.

I. Common Types of Air-Purifying Grass

Many green plants are called Air-Purifying Grass, such as lemon balm (Melissa officinalis) and curly mint, and these green plants are not the same species. Therefore, if we want to understand whether Air-Purifying Grass really has the function of absorbing formaldehyde, we first need to clarify what the real Air-Purifying Grass is. Here is a detailed introduction:

1. Lemon balm (Melissa officinalis): commonly known as Air-Purifying Grass, mint balsam, bee balm, bee balsam, of the genus Monarda. The main value of this plant lies in its leaves, which give off a lemon fragrance used to attract bee colonies to make honey; besides this, it can also be used medicinally and as food.

2. Curly spearmint (Mentha spicata 'Crispata'): also known as Air-Purifying Grass, and also a plant of the genus Mentha. Its tender branches and leaves are often used as a spice and food. In "Dian Yao Lu" and many other medical books, it is mentioned that the whole plant can treat scabies, wind-heat colds and other diseases, showing that its medicinal value is also very rich.

3. Aishi spicebush (Plectranthus 'Mona Lavender'): also known as Trisha, Mona Purple, Mona Lavender. It is a hybrid variety bred by African horticulturist Roger Jaques in the late 1990s.

4. Curly mint: this is the variety most often called Air-Purifying Grass, and it is also the subject we will discuss next.

II. Can Air-Purifying Grass Really Absorb Toxins?

Some reports claim that Air-Purifying Grass achieves a 92.4% elimination rate of formaldehyde in 3 hours and a 98.5% elimination rate in 72 hours, so Air-Purifying Grass has a very good absorption effect on formaldehyde. But is this really true? If so, could we just place a few pots of Air-Purifying Grass in a newly renovated house and then move in?

The fact is certainly not so. According to a test by a physical and chemical analysis and testing center in Beijing, per square meter, pothos absorbs 1.7 micrograms of formaldehyde, spider plant absorbs 1.1 micrograms, and Air-Purifying Grass absorbs 0.9 micrograms; as for benzene adsorption, the best effect is spider plant, followed by pothos, and last is Air-Purifying Grass. From this it can be estimated that in a room of about 10 sq m, calculated over one hour, if Air-Purifying Grass were used to absorb formaldehyde, about 200 pots would be needed; calculated over 24 hours a day, about 8-10 pots of Air-Purifying Grass would be needed.

Here two problems arise. The first is how to arrange these 200 pots of Air-Purifying Grass in a 10 sq m room. Even calculated over 24 hours, 8-10 pots would still be needed, so in that room you would basically step on a pot of Air-Purifying Grass with almost every step, and feasibility is almost nonexistent. Another key problem is that harmful pollutants such as formaldehyde produced by furniture are continuously released. It can be seen from this that trying to solve the problem of indoor formaldehyde exceeding the standard through a few pots of green plants is impossible.

III. Growing Environment of Air-Purifying Grass

1. Sunlight: Air-Purifying Grass likes places with good light. If the room has sufficient daylight, Air-Purifying Grass can be placed on the windowsill, and it is enough to keep ventilation.

2. Temperature: Air-Purifying Grass is relatively suited to low-temperature environments and can withstand the erosion of low temperatures in winter, but if the summer temperature is higher than 30°C, the growth of Air-Purifying Grass will be restricted.

3. Watering: it can be watered once every 3-5 days. Air-Purifying Grass has a strong self-repair ability. If the branches and leaves wilt, as long as water is replenished immediately, it can recover quickly. The water can be clean water or rice-washing water; clean water is best if it has been sunned in the sun.

4. Pruning: Air-Purifying Grass grows very fast. It is recommended to prune once a week. Leaves with black edges or old withered leaves can all be cut off directly.

5. Pests: because Air-Purifying Grass contains volatile oils, it can sterilize and absorb harmful gases. Under normal circumstances, there are no very serious pest problems.

The above is the relevant answer to whether Air-Purifying Grass can absorb indoor formaldehyde. Summarizing the above content, it can be seen that Air-Purifying Grass does have a certain adsorption effect on indoor formaldehyde, and besides Air-Purifying Grass, many green plants have the function of adsorbing formaldehyde. However, if you want to completely solve the indoor formaldehyde problem through a few pots of green plants, it is unlikely. The fundamental measure to solve the formaldehyde problem is still to maintain good indoor ventilation.