As we ring in the New Year, Hannah Stephenson asks the experts to predict what's going to be 'growing' in popularity over the next 12 months.

We've had a year of greening up the urban landscape, cacti craziness and working out how to reduce plastics in gardening in 2018 - but what's going to be trending for the New Year?

1. Go tropical

Louise Golden, head of garden at Dobbies Garden Centres, predicts the 'Afrique' tropical look is going to be big next year.

"People are going for a big, lush feel to their gardens, depending on where they are living. If they're further south, they can do that in their gardens, while in the north, they can plant in pots and pull them into sheltered places.

"Big, dramatic plants - such as cordylines, canna lilies and hardy palms - are going to be on-trend, and richly-coloured foliage bedding plants, such as coleus with amazing leaf patterns, will give gardens that wow factor.

"People are wanting to experiment with something new, and the younger generation is interested in the challenge of growing something regarded as a bit more tropical."

2. Boost urban spaces

Living walls are still popular for those who have little space and need to grow plants vertically, says Golden.

"They're really easy to install and you can buy self-watering units," she says. "You can use them outside on balconies or to green garage walls."

Put outside lights above them to add emphasis, and grow herbs in them, which you can add to barbecued foods and salads in summer.

Self-watering containers and window boxes will continue to gain popularity in 2019, particularly for gardeners with little time, and if we continue to have hot, dry summers, she predicts.

3. Set the mood with smart lighting

Use carefully-positioned lighting to pull your focus on to a specific area within your garden, turning a tree into a prominent feature, suggest landscape designers the Rich brothers, Harry and Dave, who work on BBC One's Garden Rescue and have now teamed up with Signify lighting (signify.com/en-gb).

Use colour to transform the ambience of your outdoor space for any occasion, whether it's a warm white light for a cosy evening, or some bright tones to accentuate a feature, they suggest.

4. Keep upcycling

"One trend that we saw last year was upcycling - people taking an item such as a chest of drawers that they'd painted, and then opening the drawers at various levels and planting it up. That's set to continue," says Golden.

"I've also seen a trend with upcycled enamelled containers used for planting things like chillis."

5. Zone in with low walling

Creating 'rooms' or divisions within an outdoor space has become a trend in its own right, adding structure and a sense of complexity to any garden, the Rich brothers observe.

The brothers often match the same texture and tone of a low wall to the house, using the same or similar stone.

Low walls can define and act as boundaries to certain spaces, or they can double up as seating. They provide structure and height, zoning different sections for various uses, and if they're subtly lit, can show off form and structure, they say.

6. Create Nordic calm

"This is where the garden is a lot more calming," says Golden. "It's green, with glossy foliage and is mainly evergreens, so it's quite tidy with clean lines. It works really well for people who don't have much time, as it's low-maintenance," she adds. White hydrangeas could be added for cool colour.

"Large-leafed plants such as Fatsia japonica and lush green ferns work really well in these schemes," Golden continues. "You can bring the look indoors too, with ferns and white orchids, which create a calming space and a feeling of wellbeing."

7. Accessorise with shrubs

Shrubs are so versatile, providing subtle layering, screening and colour.

The Rich brothers note: "Cornus (dogwood) is a great species for 2019, which naturally adds character and a splash of a winter palette through their stem colour. Philadelphus (mock orange) is a great choice for fragrance, while Daphne 'Darjeeling' is a great choice for the winter season.

Gardeners should be lighting up shrubs to add a different dimension, showing off-stem details, but also helping to illuminate the surrounding perennials that are positioned under the skirting of the shrub, the brothers suggest.

8. Make waves with the coastal look

"This is going to continue to be popular, because of everybody's love for succulents. Grasses, succulents and eucalyptus will be the on-point plants for a coastal look," says Golden.

"Those glaucous blue shades look great for these schemes, and there's a great new shrub called Senecio 'Angel Wings' which is silvery, with very large leaves - it looks great with the blue of eucalyptus and cortaderias pampas grass, to form the coastal look."

9. Take cacti outdoors

So, while the majority of cacti will remain indoors, Dobbies Garden Centres is introducing some hardy prickly pears (opuntias) which you can grow outdoors.

10. Make space for an adult hideaway

The Rich brothers' favourite trend is towards creating an outdoor hideaway to inspire you to spend more time in your garden, whatever the weather or time of day.

"Think of this outdoor structure in the same way you would consider styling your living room or kitchen; this could be carrying on a theme from the interior of your home," they suggest.

"Add some personality with a touch of colour," they add. Leaving the structure untouched, of course, provides a more rustic and natural feeling, whereas painting the wood in a more calming colour will create a cool, understated look.