A pet peeve of mine are hedges that are not green. There I said it! Hedges should be green walls*.
They perform many functions in the garden, such as screening neighbours or unsightly fences, a sense of enclosure, providing a backdrop for planting, delineating garden rooms or drawing one’s eye around the garden, bordering paths to contain deciduous leaves, filtering wind and buffering noise.
But they must be green.
Now they don’t have to be green all the time, hornbeam (Carpinus betulus) hedges can look very beautiful with their brown leaves in Autumn and Winter, and of course Camellia sasanqua hedges looks beautiful in flower. However those Photinia ‘Red Robin’ hedges, or worse Duranta 'Sheena's Gold', variegated Euonymous, or Golden Leylandii hedges are ugly eyesores. Instead of being peaceful green backdrops they are garish attention seekers. Photinia ‘Red Robin’ especially annoys me here in the Blue Mountains for the way its new spring growth clashes with the spring blossoms. Even Pittosporum tenuifolium ‘Silver Sheen’ or other variegated types are missed opportunities for a lovely wall of green — in my opinion ‘Green Pillar’ is the better choice. But even darker green, would be my choice.
I also do not think that Azaleas make good hedges because of pedal blight and Azalea lace bug infestations. You really don’t want to plant a hedge that has to be sprayed with toxic fungicides or pesticides to look good!
Many Syzygium Lilly Pillies also have red or pink new growth in Spring. Not as garish as ‘Red Robin,’ however with the psyllid and myrtle rust that Lilly Pillies are prone too, it is often better to choose something else.
Feel free to ignore my opinion, it’s your garden and you can grow whatever you like! But below I have some hedge recommendations.
*A note, I am not talking about plants you put in a line such as Lavender of Nepeta. or a screen of Hawthorn or Geulder rose, which you do not shape, I am defining a hedge as something you keep clipped to a regular shape whether tall or short.
Some great green hedging plants:
Short
Buxus sempervirens (English box)
Buxus microphylla (Japanese box)
Euonymus japonicus microphyllus ‘Tom Thumb’ -good box substitute
Lonicera nitida — fast growing
Westringia ‘Aussie Box’
Pittosporum tenuifolium ‘Golf Ball’
Hebe ‘Emerald Green’
Tall
Pittosporum ‘Green Pillar’ - good for a tall hedge in Sun
Viburnum tinus
Laurus nobilis
Ficus hillii ‘Figaro’ or ‘Flash’ (smaller than the straight species, which if left unmaintained can develop invasive and destructive roots) *frost free zones
Camellia sasanqua cvs.
Thuja plicata (a shorter and less risky alternative to Cupressus leylandii hedges)
Carpinus betulus (hornbeam)
Let me know in the comments if you would like more info on the best hedging plants for particular situations etc.