Q: It’s not so much a gardening problem as a problem garden, or more precisely a problem garden owner, with no clue. I have a north-facing garden overshadowed by neighbouring trees. It is long, so it gets some easterly sun in the earlier part of the day. I’d be happy for now with one long full nice looking border/bed. It was planted nine years ago and has got out of control. Some plants failed (eg lavender) and were initially replaced by me, but I don’t really know how to figure out the soil type despite reading tips etc. Dandelions and tough scrubby grass like it! Any advice you could give on what I need to do to the soil and/or what I could plant would be greatly appreciated. MM, Dublin
A: By their nature, north-facing gardens are typically dry and shady. Add the challenge of additional shade cast by those neighbouring mature trees, and it’s no wonder that you (and some of your plants) are finding it a struggle. Those lavender bushes, for example, gave up the ghost because there wasn’t enough heat and sunlight for this sun-loving, sweetly-scented, Mediterranean shrub to thrive.
But the good news is, that even a north-facing garden will still have areas that catch the morning light (east-facing) and evening light (west-facing), so not all of it sits in deep shade all day. Equally, not all parts of a north-facing garden are bone dry, with the driest areas typically to be found against any north-facing walls or buildings.
In your garden’s case, the fact that almost all of the plants growing in your existing border are species that like to grow in light or partial shade and in fertile, moist but well-drained soil tells us that this section of the garden isn’t in deep shade (phew) and that the soil isn’t challengingly dry (phew again).
you’re right to want to revamp the existing border, which looks like it needs a ruthless edit, in terms of plant spacing, as well as the species used. Some have run out of room (those poor hollies are being badly squeezed) while others such as the small ornamental grasses need to be lifted and used towards the front of the border. I’d also jettison the phormiums, which look dated and well past their best.
The use of solely evergreen species in any garden always feels oppressive, so I’d recommend incorporating some deciduous flowering shrubs and ideally at least one small, wildlife-friendly deciduous flowering tree to the back of your new border, to ring in the seasonal changes as well as to add some height. For the front, extend it out to include a mix of small shrubs, hardworking perennials and ornamental grasses to give you plenty of additional seasonal colour.
To enlarge your existing border, mark out the new edge with string. Then use a sharp spade to strip off sections of the existing grass sod (stack upside-down in a shady corner to rot down) and dig over the soil before incorporating plenty of well-rotted manure or garden compost. Alternatively, use the cardboard method outlined in this week’s column.
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Bear in mind that whatever plants you choose will need to be hardy species that are happy in the particular growing conditions that this area of your garden offers. That long list could include ornamental ash trees (varieties of Sorbus), or an ornamental hawthorn such as Crataegus “Paul’s Scarlet”; which will give you multiple seasons of interest. Some of the deciduous flowering shrubs that also like these kinds of growing conditions include hydrangea, viburnum, fuchsia and sarcococca while suitable perennials and ornamental grasses include astrantia, gillenia, rodgersia, many kinds of perennial geranium, Japanese anemones, hellebores, pulmonaria, heuchera, dicentra, hakonechloa and many kinds of ferns. Bulbs include alliums, narcissus and snowdrops. For further planting inspiration, go along to one of the Irish Specialist Nurseries Association’s many plant fairs which are held throughout the growing year (irishspecialistnurseries.com) or visit one of the many great Dublin gardens near you that are open to the public (dublingardengroup.com)
