close up fatsia japonica leaf

Fatsia japonica

Fatsia japonica at about 2 metres tall

The large deeply lobed leaves of Fatsia japonica (Japanese aralia or caster oil plant) give an instantly tropical appearance although they are quite hardy in the UK. It is also quite unusual as an architectural shrub that also flowers in winter. Mine are currently in flower December 2018.

Previously thought to be tender in Britain they have been kept as houseplants in the passed but are now commonly grown outdoors across the UK. The official RHS hardiness rating is H5 which is down to -15°c which makes them one of the more hardier evergreen jungle effect plants you can grow in cold climates.

Fatsia japonica Care and Problems

new spring growth on Fatsia japonica

Generally they are pretty hardy and often described as tough as old boots. I've grown them for many years and have experienced no significant problems.

The new growth when it appears in Spring and Autumn can be attacked by blackfly which can disfigure the leaves. You can just wipe them off with your hands. I've never sprayed them.

If there is a sharp frost the new growth can get 'burned' which turns it black, the plant will however recover with new growth and is never usually an issue.

fatsia japonicas leave droop at around -5c

One strange behaviour you will notice is that in winter if we get subzero temperatures, I noticed this in temperatures around -5c the foliage will droop. The plant looks like its leaves have been starved of water but this is a natural mechanism that protects the large leaves from unusually cold weather. As the air warms the leaves return to normal with no damage.

fatsia japonicas is winter hardy

Fatsia japonica Flowers

The flowers of the Japanese Aralia are unusual being similar the flowers of Ivy (Hedera helix) possibly slightly larger. They do look quite exotic as they start to open and appear in clumps of several white balls which will when pollinated produce small black fruits containing the seeds.

I've got a few pictures here of Fatsia flowering in November when the flowers start to form and December when they open. It is winter flowering so there aren't many flying insects around to pollinate them but they do usually get pollinated and produce seed.

fatsia japonica november flowers fatsia japonica december flowering

Fatsia japonica Varieties in the UK

a group of various fatsia

There are a number of different Fatsia forms available to buy in the UK. The most, the standard Fatsia japonica is widely grown and often used in council landscaping due to its tough, reliable nature and visual architectural impact.

These are also low maintenance evergreen plants and only really need the dead flower stalks removing if you are not saving the seeds and the dead leaves removing. As the foliage is so large there are not many leaves which means if you leave them to fall naturally there is not much to tidy up.

Fatsia Japonica

japanese aralia

With the large architectural foliage and comparatively narrow stems this is a well behaved garden plant that can provide instant impact. As it can grow to 3 or 4 metres in the UK it can add height in a small garden where a larger tree would not be appropriate.

Fatsia japonica 'Moseri'

fatsia japonica moseri

A more compact form of Fatsia can be found with 'Moseri'. It doesn't grow as tall and is purportedly said to have larger foliage although I haven't noticed any significant leaf size variation.

I have been growing this variety for several years and grows at a slower rate with regards to height although it can reach 2 metres eventually. A good alternative for those with less space.

Fatsia Japonica 'Spiders Web'

fatsia spiders web spring new foliage

Fatsia 'Spiders Web' is an unusual variegated form where the large lobed leaves are covered in white spidery variegation giving it a mottled appearance.

I have found it to be a much slower grower than the standard green Fatsia and have yet to see a mature specimen which can supposedly reach 2 metres in height. If you have limited space or want something stunning for a pot then Spiders Web is a good option.

Fatsia japonica 'Variegata'

fatsia japonica variagata variegated fatsia

There is a cream variegated version of the standard green Fatsia. I have found Variegata to perform very similarly to the green leaved Fatsia except for the variegation which appears randomly but mostly around the edges of the leaf.

Sometimes the cream patterning does not appear, sometimes there is a small amount of cream colouring on the green foliage but it looks most spectacular when large patches of creamy white variegation appear on the leaves.

Fatsia japonica 'Annelise'

fatsia japonica annelise

The most spectacular looking variegation appears on the form 'Annelise' which has cream veined leaves with dark, mid and light green variegated patterning.

I have also found that Annelise seems to grow at a slower rate compared to its green leaved relative. Again like 'Spiders Web' it looks great in a pot and this will also restrict the growth if space is a limiting factor.

Fatsia polycarpa 'Green Fingers'

fatsia polycarpa green fingers

Not strictly japonica (Japan) but polycarpa (Taiwan) a close relation and very similar in looks. This has more slender lobed foliage and overall more airy and delicate looking giving it a more exotic and tropical appearance.

It is not as hardy as taking lows down to around -5°c to -10°c, possibly hardier than the standard Fatsia polycarpa although not long term proven in the UK.