Pieris – The All-Season Shrub

Can you really get everything you want out of just one shrub? Even if your demands are many, including interesting evergreen foliage, beautiful spring flowers, intensely coloured new growth, fragrant blooms, optional sizes and relatively low maintenance – the answer is an unqualified yes; at least that is as far as Pieris or Lily-of-the-Valley Shrub is concerned, because it checks all of the above boxes.

Pieris 'Passion Frost' in a mixed spring planter

So let’s start with that eye-catching new growth which is what most of us first notice in the garden. By far the most dramatic of these is Pieris japonica ‘Katsura’ which flushes in both spring and fall with glossy, deep burgundy foliage which envelops the entire shrub. ‘Forest Flame’ (a japonica x formosa hybrid) has long lived up to its name with intense red new growth that transitions to pink, cream and lime before maturing to a deep green. The variegated version, ‘Flaming Silver’ goes through a similar transition but with the addition of white leaf margins. ‘Mountain Fire’ is another old standard, popular for its rich burgundy-red new growth that contrasts well against the panicles of snow white blooms. Pieris japonica ‘Scarlet O’Hara’ somewhat lives up to her name with a unique bronze-red flush of new leaves, while the hard-to-find ‘Astrid’ has slightly twisted variegated foliage that emerges a cheery rose-pink.

Pieris japonica 'Astrid', Pieris japonica 'Katsura' new growth, Pieris japonica 'Katsura' in bloom, Pieris 'Mountain Fire' blooms and new growth, Pieris 'Forest Flame' new growth,

Ultimate size has been a problem with Pieris as many older varieties such as ‘Forest Flame’ and ‘Mountain Fire’ can reach heights of 8’ or more with a spread of 6’, both of which can be hard to accommodate in today’s smaller gardens. That said, compact varieties are readily available with the variegated ‘Little Heath’ being one of the best. It grows 2.5-3’ tall with a spread of 2’ and flushes with rosy-pink foliage, the leaves and white blooms are both a smaller scale in line with its overall size. ‘Brookside Miniature’ grows to a similar height and has a distinct columnar form that works well in temporary mixed planters, as its glossy deep green foliage and terminal blooms provide a nice centrepiece. Both ‘Purity’ and ‘Bonfire’ have comparable mounding growth habits which require little pruning and mature at 3’ high by 3’ wide, while ‘Prelude’ (Taiwanensis Group) is even smaller at 2’ by 2’.

Pieris japonica 'Bonfire', Pieris japonica 'Brookside Miniature', Pieris japonica 'Little Heath' new growth, Pieris japonica 'Purity', Pieris 'Prelude',

Pieris japonica 'Passion Frost'

As with most ornamental shrubs, flower form and colour play a prominent role in the landscape, which is all the more reason to have a Pieris in your own garden. While the flower shape - clusters of heather-like blooms held in panicles – is somewhat the same throughout the genus, colour can range from red, pink and white and the blooms can be held upright or in elegant cascading drifts. Perhaps the most popular flower colour is red (actually it is a deep cerise pink) which makes Pieris japonica ‘Valley Valentine’ a very hot commodity in the garden centre when in bloom. ‘Passion’ is an improvement of ‘Valley Valentine’, while ‘Passion Frost’ is a variegated version with the white leaf margins contrasting nicely with the brightly coloured blooms.

Pieris japonica 'Valley Valentine'

The pinks are well represented in ‘Christmas Cheer’, ‘Pink Delight’ and ‘Katsura’, although the latter has the darkest flowers. For sheer ‘white delight’ it’s hard to beat Pieris taiwanensis ‘Snowdrift’ with its masses of cascading fragrant blossoms. For fragrance of a more compact variety, try Pieris japonica ‘Cupido’ which matures at 3’ tall and wide. Some cultivars such as ‘Bonfire’ have very erect flower panicles which emerge pale shell pink from burgundy buds, but mature a lovely white.

Pieris japonica 'Cupido', Pieris 'Flaming Silver' new growth, Pieris japonica 'Pink Delight', Pieris japonica 'Christmas Cheer', Pieris taiwanensis 'Snowdrift'.

Where to prune Pieris.

Being ericaceous plants, all Pieris prefer rich organic soils that are at least slightly acidic in pH and seem to thrive in partial shade exposures, although they will tolerate sun here on the coast. Most are hardy to USDA zone 5 but they do not like being planted in windy sites, as the overwintered flower buds are often damaged. You can feed with a rhododendron fertilizer before the buds have opened in spring and afterwards in early summer when the flowers are spent. Even moisture is important to avoid foliar scorch particularly during summer droughts and a top-dressing of fine bark mulch over the roots will help to accommodate this. Pruning is best timed for immediately after flowering and should be restricted to one or two whorls of growth, as older Pieris don’t always respond well to heavy pruning. The only pest you really need to look out for locally is Andromeda Lace Bug, a tiny insect with intricately patterned wings that feeds on the reverse of the leaf (so you rarely see them) causing unsightly yellow stippling on the topside. They often target plants growing in full sun and are active from late May to September, at which time you can use the organic pesticide Trounce to spray the underside of the foliage.

Andromeda Lace Bug leaf damage.

Lastly I like to encourage you to take solace in your gardens, because no matter what may be going on around us in these trying times we all need to appreciate our spring flowers, feel the warmth of the sun on our skin, breathe the fresh air, listen to the birds rejoice at sunrise and be grateful that we too can enjoy yet another day.

All Images Copyright 2018 MK Lascelle