In the 1980s I started working in a plant shop in Dublin City Centre called Mackey's Seeds.
I loved the weekly arrivals of houseplants from Holland. Huge trucks would pull up outside and I'd unload trolleys of ferns, rubber plants, Swiss cheese plants, yuccas and orchids. All these plants are seeing a huge resurgence in popularity now. Back then I'd buy massive ferns and exotic-looking banana plants and wrestle them home on the bus to my flat which soon ended up looking like a botanic garden.
I drilled holes into the roof, tied ropes around the rafters and hung bowls of ferns and cacti from the ceiling. Then, I started on bottle gardens. I'd buy bottles usually used to brew wine and beer and make them into mini greenhouses. To do this, I'd funnel compost and bits of charcoal into the space, then squeeze tiny plants through the opening. Spoons and forks were commandeered from the kitchen, taped to lengths of bamboo and used to plant up the landscape!
That was in the 1980s, but in the decades after that very few people were interested in having greenery indoors. Some specialists, such as Sam Smyth of Urban Plant Life (plantlife.ie) - a green haven for city dwellers in Dublin's Cork Street - continued converting people to the joys of pot plant gardens. Now he's been proven to be a visionary - because 2018 became the year that houseplants made a comeback!
The new trend started with palm- and banana prints for clothes, curtains and sofa coverings, then moved into real cacti and succulents.
Of course, social media is playing a part: a cactus shop in east London called Prick has over 10,000 Instagram followers. Another in Amsterdam, Wildernis, has 72,000.
Why has the trend caught on? Houseplants are relatively cheap and they don't demand much attention. They look great, they suit our health-aware sensibilities and we can bring them with us if we move.
However, the popularity of houseplants is probably mostly about a desire to nurture, to create a nest, to be responsible for something.
So how do you correctly nurture your houseplants? There are few basic rules. In general, the same principles apply as to outdoor plants in pots - they are reliant on you for food and water and if they get too big for their pots, they will need potting on to a bigger size.
Watering is the most common query - how much is necessary? Over-watering or "killing with kindness" is the most frequent cause for indoor plant failure. Many indoor plants will rest in winter so their watering and feeding requirements are much reduced - and as many come from the tropics they won't enjoy sitting in cold, soggy soil.
A general guide for summer is a good watering about once a week or fortnight, letting the soil dry out between waterings which allows the roots to breathe and prevents root rot.
However, the exact amounts will depend on the species, how warm or dry your house is and the size of the pot. Some species such as calathea and many ferns prefer to be a bit damp all the time.
Here's a quick rule of thumb: if the leaves are yellow, it could be over-watering. If they are brown, the plant is usually too dry.
An even temperature is best as draughty halls or sitting next to radiators with constant temperature fluctuations can be a nightmare for some plants.
Try to match the light requirements with the plants. If you're not sure, there are apps for smart phones which will measure how bright your room is and suggest appropriate species for the situation.
I have just introduced a garden range to a number of Dunnes Stores outlets - with more to come next year. Outer Spaces by Diarmuid Gavin is at 49, South Great George's Street, Rathmines, Donaghmede, Blanchardstown and Newbridge.