One of the most interesting aspects of gardening here in Ireland is that, for the first time, I am growing in conditions that suit ericaceous plants. So instead of struggling with them in pots of special compost I am surrounded by a landscape where every garden is dotted with pieris, camellias, rhododendrons and heathers. I have never been in love with ericaceous plants mainly because I have always considered them needy and resentful things requiring special treatment. Some are undeniably beautiful but some have a very short flowering period. But when you garden in an area that suits them then why not use them!
As a group they are actually fairly remarkable because they have become adapted to growing in soil that is deficient in calcium. Calcium is a trace element that is needed by most other plants and is essential for cell formation. Without it cells die as can be seen in tip burn in lettuce, bitter pit in apples and blossom-end rot in tomatoes. But Ericaceae has evolved to overcome this and they can grow in areas where calcium is absent – very acid soils and peat bogs. The problem comes when they are planted in soils where calcium is present (high pH or a pH of more than 7) where they cannot absorb other nutrients.
Last autumn, when looking for something to put in two containers with a silver, blue and pink colour scheme I chose Andromeda polifolia ‘Blue Ice’ to go with blue pansies, astelia, pittosporum and some hyacinths and tulips. The andromeda provided beautiful blue-grey foliage all winter.
Andromeda polifolia (named polifolia for its grey foliage) is a bog plant that grows wild throughout the Northern Hemisphere including bogs in Ireland and it is on the County Crest of County Offaly in the Midlands. It blooms in May with pink, heather-like flowers on the ends of the shoots.
It can be a tricky plant to please, needing moist soil, hating high temperatures and requiring good light (so sun for half the day probably) to stimulate flowering but not a hot spot that dries out. Think of how it grows in the wild, on tussocks in bogs, and you can imagine what will be likely to make it happy.
‘Blue Ice’ is actually a charmer, with distinctive foliage and masses of pretty flowers. When I come to dissemble the container in about a month’s time, the two plants will go into the new azalea beds I have made. These are actually a bit wet and the grass edge around them turns into a ‘gutter’ in wet weather so I think I may have the perfect spot for them. If I was still gardening in azalea-no-go-land I might put one in the bottom of a pot with a blueberry in to provide some extra colour and interest because, if they mature, andromeda should have a low, spreading habit and grow slowly.