Even sturdy Monsteras can get battered by rain. Many houseplant enthusiasts consider summer rain a natural spa treatment for indoor plants, believing it provides soft water, washes away dust, and offers a rare taste of outdoor conditions. However, the reality in the UK is far less idyllic.
The Problem
Indoor plants accumulate dust on their leaves, mineral deposits on their soil, and a general staleness from living in the same spot with poorly ventilated air for months. The idea of a warm summer shower seems like the perfect remedy.
The Hack
Spending time in warm summer rain is said to give houseplants a spa day: soft water reaches their roots, dust is washed from leaves, and they get a dose of outdoor conditions they may be suited to. The recommended method is to wait for a warm day when outdoor temperatures match indoor conditions, move plants to a wind-protected spot, and let them enjoy the rain for 20 minutes before bringing them back inside.
The Test
I put some tropical plants out during what looked like a light summer shower. The rain was colder than expected. One Calathea returned with darkened patches on its leaves. A Monstera fared better but was clearly knocked about by the rain. The others were fine, but the results were mixed.
The Verdict
British summer showers are not warm and are unpredictable in intensity. A cold downpour on plants acclimatised to stable indoor temperatures can cause chill damage and waterlogged soil if pots lack drainage, leading to root rot. Additionally, outdoor pests like vine weevils and slugs can hitch a ride back inside on pots. It is safer to stick to a lukewarm shower indoors, which provides the rinse without the risks.
Explore More
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- Gardening advice for indoor plants
