Mid-summer is the time when the patio are behind my house becomes filled with exotic-looking foliage plants, which now include a few scheffleras that I’ve been experimenting with. As far as the other plants I’ve been growing, I’ve tried many of the usual suspects to create a lush tropical theme, including some of the less hardy ones. I do well with Musa basjoo, Trachycarpus palms, Tetrapanax ‘Rex’ and even Dicksonia tree ferns. But I’ve decided that there’s only so much of the ‘big cover-up’ that I can do at the end of the season, so less hardy things now take a back seat.
So last winter’s biting cold was a good test to see what would survive outdoors without too much cosseting. And two of the hardier scheffleras surprised me! While I did relent and drape some packing blankets (saved from moving house some years ago) over them on the nights when temperatures dropped below -4C, they came through amazingly well. Just a few slightly browned leaves, but stems and growing tips unscathed.
I’ve had two species in the garden for about 5 years now – Schefflera taiwaniana (shown here) and S. rhododendrifolia. I chose them because they were reportedly two of the best for growing outdoors in the UK. And both have grown well.
Can umbrella plants grow outdoors
Looking very like their popular houseplant relatives, the umbrella plants, the hardier types originate from mountainous parts of the Himalayas, China and Taiwan. While the houseplants can be put outdoors during summer weather, they are not frost hardy, so need to be brought indoors in autumn, winter and spring. In the last 10 years or so, other species have been spread around the world to temperate regions where they can be grown outdoors all year round.
While I have been wary of how they will perform in cold winters, both of the species I grow are now listed as surviving cold down to between -5C and -10C by the Royal Horticultural Society. This means that they are suitable for outdoor cultivation in much of lowland UK, Ireland and Europe, as well as other temperate regions of the world.
Young plants are probably most vulnerable to frost, as is the case with many different species of plants. And therefore it makes sense that they are grown to a larger size in pots to start with so that they can be moved into a very sheltered place, under cold glass or even into a shed/garage overnight if hard frosts are forecast.
And all the while they are grown in pots or even large containers, there is a chance of intense cold penetrating through to the roots. This means that in most cases they will be more likely to survive frost when planted in the ground. They do need moisture-retentive but free-draining soil, however, and can cope with a pH either side of 7 – but not strongly acid.
Which are the best hardy umbrella plants
I started with S. taiwaniana and S. rhodrodendrifolia, both of which I would recommend. They have grown steadily, but at different rates. S. taiwaniana is making a more compact specimen, putting on about 10-15cm (4-6in.) of new stem each year, with mid green leaves as shown in the main image. S. rhododendrifolia has grown faster – 20-30cm (8-12in.) a year, with a more tree-like stature. Its mature foliage is a darker green, and it has the added benefit of producing red-rust coloured new growth in spring.
A visit to Jimi Blake’s Hunting Brook Gardens about 5 years ago, opened by eyes to S. delavayii. He grows it, and his other scheffleras, under the shelter of trees – something that I had mimicked with my plantings, setting them under the crowns of some large fan palms. This helps to divert the worst of any intensely cold, descending air away from the scheffleras.
S. delavayii is altogether a more chunky offering with large, glossy foliage composed of big individual leaflets. It makes stocky plants which are topped by fantastic new foliage in the spring, which is covered in a downy ‘indumentum’ making it appear silvery in colour. I bought a young plant of this a year ago, and made sure I kept it frost free overwinter, before planting it out in late spring. That way it should get its roots established and acclimatised before this year’s cold season.
This year I’ve got a couple more young plants – another S. taiwaniana and also S. alpina. This latter is considered to be very hardy and, in some cases, produces coloured new growth. It is also quite compact in growth. Again these will be grown on in pots till next spring, moving them under cold glass if this winter is really cold. So I’m all set to increase my collection of these wonderful plants.
Where to buy hardy scheffleras
I purchased my first couple of hardy scheffleras from Crûg Farm Plants, who still list the widest range of species in the UK. Other nurseries offer a more limited range, including Burncoose Nurseries, Pan Global Plants and Kells Bay Gardens, in southern Ireland. Availability of these plants can be an issue, especially as they become more widely know, but some nurseries will put you on a waiting list, informing you when they have them for sale again.