Deep purple leaves, a hue few other shrubs can match, hang on a nut tree of 13 to 20 feet that works as a standalone specimen, in a shrub bed or within a hedge. Purple filbert (Corylus maxima purpurea) also gives edible nuts — but plant two different varieties together, or none will set.
| Name | Corylus maxima purpurea |
|---|---|
| Family | Betulaceae |
| Type | Fruit shrub |
| Height | 13 to 20 feet (4 to 6 metres) |
| Exposure | Full sun |
| Soil | Ordinary, rather light |
| Foliage | Deciduous |
| Flowering | Spring |
| Harvest | Autumn |
Growing this purple-leaf shrub is easy: care, pruning and harvesting must follow good practices if you want to have nice hazelnuts.
Preferably in fall to promote root development before winter.
But you can also plant it in any other season of the year, as long as you avoid high temperatures in summer and frost spells in winter.
It is critical that you plant 2 different varieties together to ensure fertilization and fruit-bearing.
Purple foliage generally holds its colour best in full sun and turns greener in shade, though on purple filberts the leaves commonly fade to bronze-green by midsummer even in sun.
Allow for a mature spread of several metres and keep the shrub clear of walls, paths and foundations.
Purple filberts are sometimes grafted onto plain green hazel rootstock, so check the base of the plant regularly and remove any green-leaved suckers as soon as they appear.
Choose a spot that drains freely, as this hazel resents soil that stays waterlogged through winter.
Since two different varieties must grow together for the nuts to set, it helps to know which hazels are easy to find. The purple filbert itself heads the list, followed by cultivars grown for their nuts or their twisted stems.
| Variety | Leaf or stem feature | Nuts | Mature height |
|---|---|---|---|
| ‘Purpurea’ | Deep purple leaves and purple-tinted catkins | Edible nuts in purple-flushed husks | 13 to 20 ft (4 to 6 m) |
| ‘Contorta’ | Green leaves on strongly corkscrewed shoots | Sparse, grown for the stems | 10 to 13 ft (3 to 4 m) |
| ‘Red Majestic’ | Purple leaves on twisted stems | Few nuts, ornamental first | 8 to 10 ft (2.5 to 3 m) |
| ‘Kentish Cob’ | Plain green leaves, upright bush | Long, large, good-flavoured nuts | 13 to 16 ft (4 to 5 m) |
| ‘Cosford Cob’ | Green leaves, plentiful catkins | Thin-shelled, sweet nuts | 13 to 16 ft (4 to 5 m) |
| ‘Butler’ | Green leaves, spreading branches | Large nuts, needs a pollen partner | 13 to 16 ft (4 to 5 m) |
No pruning is needed, except for the first years to speed growth up.
If you wish to reduce the branches or even out the hazel tree’s bearing, wait for the blooming to end.
Green-leaved suckers mean rootstock growth: cut them out at the base.
Thin out crossing and inward-growing stems so light reaches the middle of the bush, since shaded leaves fade towards muddy green instead of holding that deep purple.
Watch for buds that swell into round, fat balls and never open, a sign of hazel big bud mite, and pick them off and bin them before they burst.
Purple filbert takes hard cutting back to a low stool and regrows strongly from the base, but expect no nuts until the replacement stems have matured.
The hazelnuts are ready to be harvested when the fruit detaches from the branch and falls to the ground.
Gather the fallen nuts every few days, since squirrels, mice and jays readily take hazelnuts from the ground and can strip much of a crop if the harvest is left unattended.
Nuts with a small round hole in the shell have been bored by nut weevil grubs and should be discarded.
Spread the nuts in a single layer somewhere dry and airy for a couple of weeks before storing them in their shells.
The leaves are remarkable with their deep purple color. Not many other plants boast such a deep vibrant hue.
Set this tree up as a standalone, in a shrub bed, or add it to your hedge.
Hazelnuts are harvested in fall.
Even if the ornamental value of this tree is what stands out, its fruits still are edible.
It’s one of the most remarkable red-leaved shrubs.
Among other purple trees, you’ll find a striking variety of katsura, the ‘Red Fox’ katsura. There are also varieties of Cotinus (smoke tree) that have stunning violet hues.
Of course, the regular hazelnut tree has the same fruit and planting needs as purple filbert.
Read also:
Neither katsura nor cotinus will pollinate a purple filbert; only another hazel can.
Smoke tree holds its violet tones best in full sun, and like purple filbert its foliage slides back towards dull green in shade.
Katsura ‘Red Fox’ needs soil that stays cool and reliably moist, so on light, fast-draining ground that dries out in summer it is a poor substitute for the more adaptable purple filbert.
Copper beech offers the same deep purple but grows into a forest tree, far outgrowing the 13 to 20 feet of a purple filbert.
Remove suckers that grow from the base often.
