Is the Houseplant Industry Actually Sustainable?

 by Hannah Watts

As the COVID-19 pandemic hit the globe, the demand for houseplants hit a record high as more than ever people craved the nature and wildness they were unable to access during quarantine. But are these plants actually sourced sustainably and does the shipment of plants disrupt delicate ecosystems and more generally the health of the planet?

One of the central  issues with the increase in demand for house plants is that the majority are mass produced in industrial farms most of which are extremely resource intensive (ie. use of water and fertiliser) as well as having a large carbon footprint. To increase the rate of plant growth, they are brown in carefully controlled greenhouses with specific heat and lighting conditions drawing upon large reserves of energy. Consequently, when looking at the production chain of houseplants it can be seen that the biggest source of carbon emissions comes from heating the greenhouses especially in areas where they are mass produced. Large scale greenhouses also take up large portions of land that have often been cleared of trees and other carbon sinks. One example of high land usage is the coffee chain Costa whose plant farms use about 4,000 acres of land to cultivate their crops. It is important to consider that house plants bought at nurseries and garden centres have been shipped with thousands of others and thus the environmental impact of a single houseplant is limited. However, regularly buying tropical plants such as Venus flytraps have an impact not only on their environment's natural biodiversity but also carbon emissions. 

When choosing a houseplant be sure to check where they’ve been grown. In general buying native plants grown locally is more sustainable. The company Patch, self-titled as London's biggest house plant supplier, imports its plants form the Netherlands on a by order case meaning that plant air miles are often higher than buying plants grown in the UK or taking cuttings from a friend. Some growers are outsourcing their production to warmer places such as the Canary Islands - whilst this may increase the plant air miles it does decrease the energy output to run a greenhouse as plants are able to be propagated without the carbon emissions produced by heated greenhouses.

It’s not just the plant itself - many houseplants are grown in soil that contains peat. Peat is a substance formed by the partial decomposition of organic matter in waterlogged areas. Here oxygen is unable to reach the decomposing matter, causing anaerobic respiration to occur and then a build up of carbon dioxide which is prevented from entering the atmosphere. Therefore they are known as carbon sinks and it is often a desirable material to grow plants in as it has the ability to retain moisture and oxygen due to partially decomposed matter. It is also relatively inexpensive. So why is Peat not a eco-friendly potting material ? Peat bogs are massive carbon sinks containing a third of the world’s soil stored carbon. When it’s harvested the carbon storage is eliminated and carbon dioxide is also released into the atmosphere. It also regenerates incredibly slowly (1mm per year). 

So it’s clear that houseplants aren’t as ‘green’ as initially marketed but there are certainly steps you can take. For example, swapping cuttings between friends, checking the origin of growth and being sure to limit the purchase of novelty plants such as cacti and chrysanthemums which are unlikely to thrive in an uncontrolled climate such as a house. Furthermore, plants are suspected to decrease the levels of indoor pollution and are known to improve mood and reduce stress and anxiety. Therefore, while like everything we buy it can’t be deemed sustainable, purchasing houseplants in an eco conscious manner isn’t necessarily the environment and can have potentially as many positives as negatives.