Some trees will happily steal the limelight
Everybody seems to complain about acidic soils; few, if any, folk moan about alkaline soils because up here in the North, limerich soils are rare.
However, for once, let’s consider the minority who struggle on what are usually clay soils with a poor structure and very little goodness to encourage root growth.
Incorporating large amounts of organic matter can help, but the best option is to grow plants that are happy in alkaline soils – the likes of lavandula, dianthus, clematis and geranium. Shop around and you’ll find many more, but the list of trees is not quite as extensive.
Some Japanese cherries will be happy in an alkaline soil, as will a few crab apples and whitebeam, but for something a bit more unusual, there is Cercis siliquastrum, better known as the Judas tree, because, supposedly, it was from one such tree that Judas Iscariot hanged himself.
It is deciduous, it’s related to the pea family, can grow to 40ft or so in height and it produces clusters of rosy-pink flowers. And it is relatively hardy – down to around -15C.
It loves the sun but likes its roots to be kept cool and moist. Never plant it in a windy spot or try to move it once it has become established.
Young growth is sometimes prone to frost damage, but Cercis siliquastrum tends to regenerate well. Pruning isn’t necessary other than to remove dead wood. If the tree threatens to get too big, cut it back in mid-to-late spring after flowering.
For something even more eye-catching, there’s the Scotch laburnum, Laburnum alpinum, which in late spring produces sprays of fragrant, vivid yellow blooms followed by brown seed pods – the seeds may look like peas but they are poisonous.
It tolerates most soils but prefers a well-drained alkaline loam and a slightly sheltered site. A mature specimen is unlikely to grow to more than 25ft in height and probably the same in width.