Why moth orchids make perfect housemates

These little beauties even tell you when it’s time to water them

Pretty in pink: the easy-to-care-for Phalaenopsis.
Pretty in pink: the easy-to-care-for Phalaenopsis. Photograph: Alamy Stock Photo
Pretty in pink: the easy-to-care-for Phalaenopsis. Photograph: Alamy Stock Photo
James Wong
Sun 13 Dec 2020 03.15 EST

In the traditional, deeply nostalgic world of gardening, it’s amazing how quickly some things can change. When I was a plant-mad teenager back in the 1990s, the moth orchid, Phalaenopsis, was considered an unbelievably rare new introduction that cost a fortune and was only available in a few colours. Fast forward just a few decades and they are now sold for no more than the price of everyday bedding plants at supermarket checkouts and garage forecourts everywhere. But this immense spike in popularity is not without good reason, so here is my guide to getting the very best out of them.

Hailing from the shaded forest branches of the cool, highlands regions of southeast Asia, moth orchids are in many ways the perfect houseplant, as they are adapted to essentially the exact environmental conditions we humans like the most. In terms of light levels, temperature and humidity, if you are happy to sit and read in a particular spot wearing a T-shirt and jeans, they will love it there too. So, with these factors automatically ticked off by meeting our own needs, there are only three other things to bear in mind when it comes to spoiling these plants: water, fertiliser and pruning.

Pretty in pink: moth orchids.
Pretty in pink: moth orchids. Photograph: Blickwinkel/Alamy Stock Photo

Watering some plants can be tricky because with their roots hidden away in opaque pots it is often hard to gauge how much water they need. Not so with orchids. In fact they will even tell you what they require by changing colour. As a general guide, if the leaves are green, they are happy. If silver or white, they could do with a drink, especially if slightly wrinkled. All you need to do is plunge the pot in a sink or bowl of water for a minute or two and then drain it thoroughly. If they are brown, that’s a sign of rot, caused by overwatering. Trim off any affected areas and continue as per normal. There is some internet talk of ice cubes being used, which is a bit of a cultural misunderstanding. This is a technique used in the lowland tropics to cool the root zones of these highland species, allegedly encouraging flowering. In our living rooms, there is no need to do this.

What about fertiliser? Advice varies on this topic, but for me I just add a half-strength liquid orchid fertiliser at every watering, year-round.

Finally, let’s talk pruning. There are different schools of thought on this as these notoriously free-flowering plants are indeed capable of producing small lateral branches of blooms from dormant nodes once their initial flush has ended. However, I find these side branches can look a little messy, producing much smaller flowers, which rather ruins the elegant architecture of this genus. Snipping whole flowering stems back to soil level will encourage the production of new ones, which will give you just as many blooms that are not only larger but better formed.

There really isn’t anything else to add in terms of caring for these flexible, free-flowering plants: hence the reason for their popularity.

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