In everyday talk around our gardens, we often talk about cypress trees, but that name seems to cover many trees that look very different from each other. So what is going on with all these ‘cypress’? The name is an old one, going back to the ancient Greeks and Romans, and was applied to trees that were evergreen, with green branches, but that didn’t have the obvious leaves of, say, an oak tree. That wasn’t so bad when there were just the few trees like that which exist in Europe, but once exploration and settlement began, that name stuck to trees that looked only superficially similar. Rather like calling your postman ‘Jack’, because he happens to look a bit like your Uncle Jack. Once you become a little more involved in gardening and start to look more closely at the plants available to you, then the name becomes a bit of a handicap, with so many variations. Let’s look at these ‘Cypress’ plants more closely, and try to sort out, with the help of the system of scientific names, those different plants – what they are, and how best to use them in our gardens.
The True Cypress
A superb tree, seen growing across Italy and southern France, is the original cypress tree, which we usually call Italian Cypress. This narrow column of dark green is a wonderful tree that is drought-resistant and long-lived. It makes beautiful accent specimens, and hedges or screens too – as long as you live in zone 7, and preferably zone 8 or 9. Called Cupressus sempervirens, this original cypress tree has some important relatives around the world, that are also called by botanists ‘Cupressus’.
When explorers and naturalists arrived in the Pacific Northwest they discovered vast forests of towering evergreens that turned out to be related to the Italian Cypress. This tree is Cupressus nootkatensis, the Nootka Cypress. Further south, into southern California, there is another tree, the Monterey Cypress, Cupressus macrocarpa. These are important forestry trees, but rarely grown in any but the largest gardens. It was in such a garden, in England, that a chance hybrid was created between them, creating the Leyland Cypress. That remarkable plant is among the fastest growing trees around, and it is widely grown today for hedging and screening. It is available in some variations too, with different foliage colors, such as the beautiful gold of the Gold Rider Leyland Cypress. This great tree also comes in denser, more compact forms, of darker green, such as Emerald Isle, or the very hardy Murray Leyland Cypress.
Although the Nootka Cypress is not often grown in its wild form, because of its size, for lovers of the exotic and marvelous, there are some wonderful special forms of this tree. Since it is much hardier that the Italian Cypress, and grows well even in zone 4, these are great cypress trees all across the northern states. A remarkable form is the Weeping Nootka Cypress – more often called by its alternative name of Weeping Alaska Cedar. It has an almost unique combination of an upright trunk with weeping side branches that often cascade all the way to the ground. For a striking specimen reaching about 30 feet in height, this is a top choice. Even more exotic is the variety called ‘Green Arrow’, where the weeping side branches head downwards the moment they leave the trunk, creating a very narrow form. Each plant becomes a unique individual, and each one is a prized specimen for the garden.
It is worth mentioning that botanists are still struggling to accurately place the Nootka Cypress in their classifications, so you may also see this tree variously named Chamaecyparis nootkatensis or Xanthocyparis nootkatensis. These names all refer to the same plant.
The False Cypress
When plant collectors and botanists arrived in Asia, they found trees that looked very like the familiar European cypress, so they called them ‘cypress’ too. One obvious difference is that their branches form rounded, fan-like sprays on these trees, and botanists called them Chamaecyparis. Some are also found in North America – further proof that our present continents were once joined together. For gardeners the most important are the two Japanese species. One is the Hinoki Cypress, Chamaecyparis obtusa, and the other is the Sawara Cypress, Chamaecyparis pisifera. These trees are similar in the wild – tall forest evergreens with scented wood, that the Japanese value for building temples. In the garden they are usually grown as dwarf specimens, often with golden foliage, thread-like branches, and other special characteristics.
Hinoki Cypress typically turns beautiful shades of red in winter, but for gardens the most valuable are the numerous forms with yellow and gold branches. These are usually dwarf plants forming globes or pyramids, of dense, slightly irregular forms. They can be clipped into neater forms in you wish, although unclipped they probably have more character.
The Sawara Cypress comes in three distinct foliage forms. These give us a whole range of very different looking evergreens, making this plant the source of many wonderful ornamental dwarf evergreens. One group of plants have soft, mossy foliage, and are the ‘squarossa’ type. An example is the wonderful Baby Blue Sawara Cypress, which forms a dense, blue irregular cone, reaching perhaps 6 feet tall in ten years. Other trees have branches that are more feathery, and they are called ‘plumosa’ types. The popular variety called ‘Gracilis’, or the Slender Hinoki Cypress has these kinds of branches. Finally, there are forms with narrow, often twisted, rope-like branches, called ‘filifera’. A lovely example of this is the popular ‘Aurea’ variety, called the Sungold Sawara Cypress. It grows into a beautiful broad mound of golden branches, looking especially good during the winter months, when our gardens certainly need a golden touch.
One of the two American species is something rare in conifers – a lover of wet soil. The White Cypress, Chamaecyparis thyoides, is an ungainly tree that grows in swampy areas of the South. In its wild form it is only fit for the most natural of gardens, but there is a form called ‘Red Star’ which grows into a dense, upright bush, perhaps reaching 20 feet tall in time. It has wonderful red foliage all winter, and bluish foliage in summer. Tough as nails, pest free and hardy to zone 4, this ‘cypress’ is a terrific choice for awkward wetter parts of the garden, although it will grow perfectly happily in regular garden soil too.
The Bald Cypress
We can’t leave a discussion of the different cypress trees without mentioning another American tree that must have greatly confused early settlers. With typical ‘cypress’ foliage in summer, this tree literally does turn bald in winter, when the clusters of small branches drop to the ground. Only three other evergreens have this deciduous habit, plus, the Bald Cypress also grows even right in water – as it does in the Florida Everglades. It is a great tall tree – 50 to 70 feet tall in time – that is surprisingly hardy even into zone 4. If you have a river or lake, plant one along the edge or even in the water. Over time these trees send up ‘knees’ – growths from the roots that project above the water and bring oxygen down to the mud where the roots are living. A great conversation piece and a lovely tree too, this is another cypress tree for the right garden.