I have previously written about some of my favourite ornamental trees, some of which have eye catching autumn leaf colour and
others which flower beautifully in spring. The other trees and shrubs which stand out in our region’s gardens are those that have different leaf colour throughout the growing season-not just in autumn.
The first tree I think of is the golden robinia in our garden. It’s lovely to see the golden leaves of this hardy tree contrasting with the green/blue leaves of a big gum tree (Eucalyptus scoparia) standing next to it. We also have a golden ash which has lemon coloured leaves and yellow bark on young branches which contrasts distinctively with the dark green leaves of a big oak tree behind it. Golden elms are of course the other magnificent specimen tree with golden foliage throughout the growing season, although many of them in the district have been badly affected by the elm leaf beetle in the last few years.
Purple leaf trees and shrubs are another opportunity to achieve beautiful contrast in the garden. Crimson Sentry maple is a hardy, medium size tree that has dark purple leaves throughout the growing season, asdoes the Royal Raindrops crabapple which also has eye catching dark pink flowers in spring. Quite well known across our region are the purple leaf flowering ornamental plum (Prunus nigra) and its narrow growing form Oakville Crimson Spire-these are probably the hardiest, most heat tolerant of the spring flowering, purple leaf deciduous trees. Less hardy, but well suited to a small protected space in your garden is the purple Japanese maple (Acer palmatum atropurpureum) which has striking red/purple leaves throughout the growth season.
Finally, there are the variegated leaf trees such as the Box Elder (Acer negundo)- including a cultivar called Flamingo which has green and cream variegated leaves that have a pink colouring when the new leaves emerge. Another variegated leaf tree we have in our garden is the silver elm-a large, rounded tree that is great as a specimen tree in a round driveway area.
Ian Rogan
Millthorpe Garden Nursery