How to grow ranunculus indoors - 5 failsafe tips for perfect flower-of-the-moment blooms

Hot on the heels of the dahlia trend and a peony obsession that launched a thousand Instagram accounts, cottagecore planting shows no signs of waning. And the next bloom to step into the spotlight? Seeing as you asked, it's ranunculus. 

Ranunculus is actually the umbrella name for a genus of flowering plants in the Ranunculaceae family (also known as the buttercup family) which counts over 2,000 species as members including anemones, clematis and hellebores. The plump, heavy-headed ruffled blooms we recognise as ranunculus are the ranunculus asiaticus variety – delightfully nicknamed the Persian Buttercup. Grown in a glorious spectrum of colors from punchy sunset hues to sweet sugar almond pastels, a sudden uptick in popularity means they're finding their way into wedding bouquets and domestic windowsills alike.

'Social media has a way of propelling certain flowers into stardom and we’ve seen this with the emergence of so many new dahlia, tulip and ranunculus varieties on the market. We’re now noticing more cottage style flowers making their way back into gardens and homes,' says Hattie Shackleton, a grower and florist of Honour Farm Folk .

As cool season flowers they thrive in the months of spring, bringing bursts of joy before summer's heady temperatures take hold. 'Over the past couple of years we’ve seen the great revival of the dahlia and so it seems only right that the most beautiful gift of spring, the ranunculus, has its moment in the spotlight,' adds Hattie 'For growers like myself, the ranunculus – much like tulips and the narcissus family – represent hope and promise for the high season ahead.'

For those of us not blessed with a cottage garden, or if you're simply looking to invite the outdoors in to pep up your dinner party tablescape, here's how to grow your very own indoors.

How to grow Ranunculus 

1. Prep your rhizomes (that's bulbs to you and me)

To encourage healthy root systems to develop and get your ranunculus off to a flying start, rhizomes can be pre-sprouted in shallow trays of soil before being planted into pots in late autumn for spring flowering, or in late winter for summer blooms.

'Typically I grow varieties that will perform well as cut flowers and provide me with long stem length for arrangements,' says Hattie. 'However, a variety which is perfect for indoor growers is the ‘Tomer Mix’ (dwarf buttercups). They come in a variety of colors and are lovely and compact, which makes for a striking and playful arrangement when clustered together in pots.'

2. Choose your vessel

These blousy blooms look charming planted in a clutch of ramshackle terracotta pots or tumbled together in an elegant delftware bowl or giant clam shell planter, though ranunculus are sensitive to overwatering so when grown indoors, good drainage is essential. 'A good quality multi-purpose compost will supply all the nutrients the plant needs, while a handful of horticultural grit will allow excess water to drain away,' advises Hattie.

If you want that wow factor, don't be shy of overcrowding: 'I have to confess I'm guilty of overcrowding pots as I love a full show. When you put so much time into tenderly growing your own flowers you really want that full pay off and breathtaking moment at the end,' she adds.

3. Follow the sun

While happy in partial shade, ranunculus will thrive in full sun so a light-drenched windowsill or basking spot on the breakfast table will help them reach their full potential, and pots can be luckily be moved accordingly. Just be careful not to allow your pot to entirely dry out: potted ranunculus can dry out easily thanks to their fleshy, tuberous roots so a good rule of thumb is to water weekly or whenever the soil feels dry just beneath the surface.

4. Beware of pests (and root rot)

'Ranunculus attract a number of pests such as aphids who feed on young growth quite mercilessly,' warns Hattie. 'This can be rectified by close inspection of the plants on a daily basis when they’re taking off and a simple soapy water solution in a recycled spray bottle on infected areas.'

Like many tuberous plants, ranunculus are also prone to root rot which can prove problematic in waterlogged garden areas and overwatered pots with poor drainage. After watering, be sure to regularly tip out any excess water that has collected in the saucer underneath and if you plan to revive your ranunculus next year, gradually reduce watering as the summer progresses so the rhizomes have time to dry out before they become dormant.

5. Cut with caution

Enjoy the fruits of your labor to the full with cuttings for the rest of the house (or deserving friends if you're feeling generous), but practice restraint with young plants. 

'Like with many species used for cut flowers, the ranunculus asiaticus is a cut and come again plant. But you must be patient and not go in too heavy, especially when harvesting from a young plant,' says Hattie.