Monday, 1 September 2014

Leyland's Cypress and a problem with hybrids

People who have visited our new home will have seen that the garden area is very limited; the front garden is tiny whilst the back garden, though about three times as large, is slabbed over to create a courtyard. We are perfectly happy with the dimensions and to grow a range of interesting plants will be a challenge to our imagination and creativity.

A short but bulky hedge of Leyland's Cypress forms the western boundary at the back. By bulky I refer to the fact that, though only about 7 metres long, it is close to two metres thick. It has to go, and I have already made a start.

While many people curse this tree it is nevertheless of considerable interest. Its 'Latin' name is x Cupressocyparis leylandii, and the 'x' that prefaces the name hints at its most curious feature. For the non-botanist, he usual type of hybrid is a cross between two species and there are many thousands of these, such as the cross between Crocosmia pottsii and C. aurea. The result is 'Montbretia' (Crocosmia x crocosmiiflora), a hybrid so vigorous and invasive that it has become a serious problem in New Zealand, Australia and the U.S.A.

A start has been made on cutting back the Leyland's
Cypress. 1 Septermber, 2014
Leyland's Cypress is a cross between two plants in separate genera, and is therefore a bi-generic hybrid, which is why the 'x' is placed before the name. These are much rarer. 'Leylandii' is a hybrid between the Monterey Cypress, Cupressus macrocarpa and the Nootka Cypress, Chamaecyparis nootkatensis.

Why am I banging on about this? The fact is that hybrids, e.g. Montbretia, can often be extremely vigorous, bi-generic hybrids equally so. Many people have paid the price for under-estimating the vigour of 'Leylandii'. Nevertheless, to be fair it does make a very good hedging plant if it is clipped regularly.

Sambucus 'Black Lace' 1 September, 2014
As I say, it is being removed as quickly as possible and, truth be told, only one plant left by previous owners is likely to survive. This is the lovely, dark-leaved Sambucus 'Black Lace'. Here it is in the front garden, with a red rose scrambling through it. This elder is a sport of our common hedgerow elder and, with its finely dissected (laciniate) leaves and pink flowers is a gorgeous thing. It will have to be moved, but the fortunate accident of a red rose scrambling through it is worth repeating.

Raindrops bejewel the laciniate leaves of Sambucus 'Black Lace'
Trinity Close, Daventry. 1 September, 2014

The raindrops on the Sambucus leaves indicate the conditions. Work on clearing the Leylandii will have to be put on hold.

No comments:

Post a Comment