Casual Gardener: Healthy houseplants, healthy mind

Healthy plants have a positive effect on the way people feel about their indoor environment. Picture by Tim Sandall/RHS/PA
Healthy plants have a positive effect on the way people feel about their indoor environment. Picture by Tim Sandall/RHS/PA

I'M a big fan of houseplants, and while many are shifted outdoors over the summer months, our home at this time of year is still replete with a variety of exotic and eye-catching foliage. While the role of indoor plants in improving the air quality in our homes and offices is often exaggerated, there is no doubt that they give a healthy boost to well-being in a domestic or work environment.

However, according to new research from the Royal Horticultural Society (RHS) and the University of Reading, neglected plants can be worse than none at all.

The study looked at people’s perceptions of wellbeing and their mood responses to viewing different houseplants.

The participants scored plants on how beautiful, interesting, uplifting and relaxing they found them, with preferred plants found to give the greatest benefit to people’s well-being. Healthy plants with a dense canopy resulted in the most positive effects on the way people felt about their indoor environment.

Those that elicited the most positive reactions were lush, green plants with a rounded, dense canopy – similar to that of popular houseplants such as weeping fig (Ficus benjamina), Calathea and Swiss cheese plant (Monstera deliciosa).

Palms were found to have particularly positive associations, as they reminded people of holidays and happy memories. People thought the most ‘beautiful’ plants were those with a softer, rounded canopy, such as devil’s ivy (Epipremnum aureum) but there was no preference for any particular shape.

Conversely, unhealthy plants were found to reflect negatively on people’s perception of their indoor environment, and researchers recommend removing them.

Principal horticultural scientist at the RHS Dr Tijana Blanusa said: “This study adds weight to the important role houseplants can play in improving mental health and well-being in the indoor environment.

"Not everyone has a garden, but most of us can find space for a houseplant."

Five low-maintenance plants for the home and office include:

:: The ZZ plant (Zamioculcas zamiifolia) is an evergreen with smooth, shiny leaves on upright stems that doesn’t take up much room. It can grow in full shade, doesn’t require a lot of water and is very tolerant of neglect, so it won’t start to look unhealthy.

:: Mother-in-law’s tongue (Sansevieria trifasciata) is one of the hardest houseplants to kill, making it perfect for beginners wanting to feel the benefits of houseplants. Its leaves won’t flop or spread and it is very tolerant to shade. It won’t need much watering – in winter it only needs a top up every month or so.

:: Devil’s ivy (Epipremnum aureum) is an evergreen climber with glossy leaves and dense canopy and is one of the best houseplants for filtering the air. It is relatively low maintenance, but it does need moist soils and would appreciate misting with water to keep leaves glossy and healthy.

:: Spider plant (Chlorophytum comosum) is another good choice for beginners as it can tolerate a range of conditions. Ideally they like indirect light and regular watering. It will reward you with fast growth and runners with tiny plantlets that can be potted up as new plants.

:: Aloes are easy-to-maintain succulents that come in a variety of shapes and sizes depending on the species. Most like full light and not too much water or humidity. Aloe vera is known as the medical aloe because the gel inside the leaves can be used to cool and soothe skin.