Protecting Plants From Air Pollution: A Guide

As the world grapples with climate change, pollution, and other environmental issues, maintaining good air quality is more important than ever. While plants are exposed to various harmful air pollutants, which can cause oxidative stress and impair their growth and productivity, they also play a crucial role in protecting us from air pollution. This dual vulnerability and resilience of plants to air pollution highlight the importance of understanding how to safeguard them from its adverse effects. By comprehending the mechanisms through which plants defend themselves against air pollutants, we can develop strategies to fortify and protect them, ensuring their health, and in turn, our own.

How to protect plants from air pollution

Avoid overwatering plants to prevent mould growth, which can be harmful when inhaled

Mould is a type of fungus that thrives in moist environments. While it is a normal part of plant care, certain conditions can lead to excessive and harmful mould growth. One of the most common reasons for mould formation is overwatering plants. Mould spores are present in the air and settle on plant leaves, flowers, or soil, leading to mould growth.

To prevent mould growth, it is crucial to avoid overwatering plants. Ensure that your plant is in a pot with suitable drainage holes, allowing water to drain through the plant properly. If your pot does not have a drainage hole, you can create one by drilling a hole in the bottom. It is also important to use a pot that is appropriate for the plant's size.

In addition to proper drainage, providing adequate ventilation for your plants is essential. You can improve air circulation by spacing out your plants, ensuring they have enough breathing space. If your plant is on a windowsill, opening the window can enhance ventilation and expose the soil to sunlight, which helps inhibit mould growth. If natural air circulation is not feasible, using a small fan blowing across your pots can effectively reduce humidity and prevent mould-favouring conditions.

By following these measures and avoiding overwatering, you can significantly reduce the risk of mould growth on your plants. Remember that mould can be harmful to both plants and humans when inhaled, so taking proactive steps to prevent and address mould is crucial for maintaining a healthy environment.

Choose plants with large leaves and no flowers to reduce allergies

When selecting plants for your home or garden, it is important to consider the impact of air pollution on their health and growth, as well as how they might affect your allergies. While plants can act as a defence against air pollution, they are also exposed to harmful pollutants, which can cause oxidative stress and impair their growth and productivity.

To reduce allergies, it is recommended to choose plants with large leaves as they can trap and filter out airborne pollutants, improving the air quality around them. Additionally, large-leaf plants with no flowers can further minimise allergies. This is because wind-pollinating plants, which include certain grasses, weeds, trees, and flowers, tend to be the worst for allergies. They produce small and lightweight pollen that easily becomes airborne and inhaled, triggering hay fever and other allergy symptoms.

By opting for plants without flowers, you can avoid the release of pollen altogether. Deciduous plants, for example, shed their leaves seasonally and release pollen from their flowers, so they may not be the best choice for those looking to minimise allergies. Instead, consider plants that rely on insects or birds for pollination, such as those with large trumpet or bell-shaped flowers. These plants attract pollinators with their vibrant colours or multiple flowers on one stem, ensuring effective pollination without relying on the wind.

Some specific recommendations for low-allergen, large-leaf plants include St. Augustine and female cultivars of buffalo grass, such as "Legacy" or "UC Verde". These grass varieties are less likely to trigger allergies, providing a more enjoyable gardening experience. Remember, knowing your specific allergies is crucial when selecting plants, as different individuals may react to various pollen types. Consult a doctor if you are unsure, and they can help determine your specific allergens through testing.

Plant native flowers, grasses, and trees to create an ecosystem that purifies the air

Planting native flowers, grasses, and trees is an effective way to create a natural ecosystem that purifies the air. This approach not only enhances the aesthetic appeal of any space but also contributes to a healthier environment. Here are some insights into how native flora can create a purifying ecosystem:

Native Flowers:

Native flowers, with their vibrant colours and fragrances, offer more than just visual appeal. They play a crucial role in attracting beneficial insects, such as bees and butterflies, which are essential for pollination. Additionally, native flowers have adapted to local conditions and are more resilient to regional climate variations, making them easier to maintain. Their extensive root systems help prevent soil erosion and provide a natural filtration system, trapping pollutants and improving air quality.

Native Grasses:

Incorporating native grasses into the ecosystem provides a multitude of benefits. These grasses, adapted to the local climate and soil conditions, require less maintenance and conserve water. Their deep root systems act as natural air purifiers, absorbing pollutants and releasing clean oxygen through photosynthesis. Native grasses also provide habitats and food sources for local wildlife, promoting biodiversity and a healthier environment.

Native Trees:

Planting native trees is a powerful way to combat air pollution. Trees absorb harmful airborne pollutants, including SO2, NO2, CO, and ozone, through tiny pores called stomata on their leaves. They also remove particulate matter by temporarily catching it on their vegetative surfaces, which is then washed away by rain. Additionally, trees absorb carbon dioxide, a major contributor to climate change, and release oxygen, providing a vital source of clean air for humans and animals alike.

The collective impact of native flowers, grasses, and trees extends beyond air purification. They create habitats for wildlife, enhance biodiversity, and contribute to a more sustainable and resilient environment. By selecting plants adapted to the local conditions, you not only reduce maintenance requirements but also foster the growth of a thriving ecosystem that benefits the natural world and human health.

Reduce the size of lawns as mechanical lawn maintenance adds emissions and particulates to the air

Lawns can be a secret weapon against climate change. Research by Dr. Carly Ziter found that the typical American lawn is more effective at capturing carbon than the untouched environment. However, mechanical lawn maintenance adds emissions and particulates to the air, which can be harmful to plants and the environment.

Most lawn equipment is gasoline-powered, typically with two-stroke or four-stroke engines. These engines require a large amount of fuel, with an additional amount often spilled in the process. Two-stroke engines are particularly harmful as they lack an independent lubricant system, requiring fuel and oil to be mixed. This results in about 30% of the fuel not combusting completely, releasing toxic gases into the air. A 2014 study found that the emissions from an idling two-stroke scooter were 124 times higher than those of a car or truck. While four-stroke engines are slightly more environmentally efficient, they still contribute to harmful emissions.

To reduce the negative impact of mechanical lawn maintenance, homeowners can opt for electric engines. Electric mowers and leaf blowers were previously avoided due to their higher cost and limited battery life. However, more affordable and long-lasting options are now available. While a good-quality electric mower may cost more upfront, the cost evens out over time due to reduced fuel and maintenance expenses. Electric mowers are also lower maintenance, easier to store, and do not require a cord. They produce no emissions, making them an environmentally beneficial choice.

If electric mowers are inaccessible, homeowners can make smaller adjustments to their lawn care routine. This includes reducing the frequency of mowing, switching from once a week to once every two weeks, for example. Additionally, mowing in the evening can give chemicals and pollutants time to disappear overnight as they lack sunlight. Homeowners can also limit the use of landscaping power tools, as hedge trimmers, weed whackers, and similar equipment contribute to emissions.

Avoid air purifiers that generate ozone, which can cause health issues

While air purifiers can be beneficial for improving air quality, it is important to steer clear of those that generate ozone. Ozone (O3) is a harmful air pollutant that can have detrimental effects on plants, ecosystems, and even human health.

Ozone is a reactive gas that can impair plant growth and development. It enters plant leaves through stomata during photosynthetic gas exchange or is absorbed through leaf surfaces. Studies have shown that ozone negatively impacts crop yields and quality, forest production, ecosystem function, and biodiversity. The effects of ozone on individual plants can have knock-on effects on entire ecosystems, altering the types of plants present in a given area.

In addition to affecting plants, ozone can also be harmful to humans and other living organisms. Ground-level ozone, often referred to as "bad ozone," is a significant respiratory irritant and can cause serious health issues, especially for children, the elderly, and individuals with pre-existing respiratory conditions like asthma.

When shopping for an air purifier, look for models that do not emit ozone as a by-product. There are many types of air purifiers available that use safe and effective technologies, such as High-Efficiency Particulate Air (HEPA) filters, activated carbon filters, or ionizers that do not release ozone.

It is also important to note that while air purifiers can help improve indoor air quality, they should not be solely relied upon to protect plants from air pollution. Implementing other strategies, such as selecting air-purifying plants, proper ventilation, and source control to reduce indoor air pollution, can also help create a healthier environment for both your plants and yourself.

Frequently asked questions