Pieter Janse van Rensburg tells us about an interesting and rewarding species which is a very popular subject in bonsai.
The species belongs to either the Taxodiaceae (1) or the Pinaceae (2) family and comes from the southeastern United States of America and Mexico. Other varieties also grown as bonsai are Taxodium distichum 'pendulum', it has horizontal branches with pendant tips, Taxodium ascendens (Pond cypress), Taxodium mucronatum (Montezuma cypress), considered evergreen in Mexico, but it loses its leaves outside its "hardiness zone"
The swamp cypress is a highly attractive and majestic tree that can grow to great heights. In its native country it can reach heights of thirty metres, but it seldom exceeds fifteen metres locally. Moisture is essential and it even grows in shallow water. When it grows in water, the tree develops interesting nodular aerial roots, known as "cypress knees".
Young trees have a strong upright-growing habit with 1Cl conical shape. Old mature trees, in nature, develop a flat crown. The fern-like leaves are the other attractive feature of this tree. It has two types of foliage, on long shoots the leaves are shaped like ferns. On short shoots, the 5mm to 25mm long leaves are needle-shaped and arranged in a double row. In autumn, the leaves tum a beautiful rust brown and remain on the tree well into winter.
You can propagate by softwood cuttings in spring and hardwood cuttings in autumn. An air-layering is done, using either the ring-bark or tourniquet methods. The swamp cypress is a bleeder! During the growing season, sap will ooze out of large cuts. All major work is done during the dormant season. Should it be necessary to perform major trimming during the growing season then trim the roots as well, this temporarily reduces the sap-flow. Large trees may be collected during the dormant season. To reduce the height of the trunk drastically, cut it at a slant. Allow a side shoot to become the leader and to grow unchecked for a while to promote the healing process. This species forms calluses very strongly. The wood is soft and rots easily if not protected.
Upright, informal upright and leaning trunk styles, with or without a hollow trunk, are most suited to this species. Branches look best when arranged horizontally or when wired down. When wiring the branches down it is best to tear the branch away from the trunk partially, wire the branch and seal the wound. As the callus forms the branch is set in position. Wire the branch tips down as they grow, else it will lift as the tree grows. Secondary branches form readily, but tertiary branches are slow to develop. The fine foliage, however, makes up for the lack of tertiary growth.
Equal parts coarse sand, loam and compost make the best growing medium. The soil must have high moisture retention and the tree will grow if you stand the pot in a tray of water. . Fertilise regularly from spring to autumn with a balanced fertiliser. This is a relatively pest-free species, but aphids love the young new shoots in spring and borers can attack untreated and unsealed wood.
The most suitable pots are soft-cornered round and oval, shallow to medium depth pots. Choose the colour of the glaze to show off the rust autumn colour or the beautiful soft green in spring. They look very good in a mottled blue, off-white, soft yellow or biscuit-coloured pot.
- The International Book of Trees. Hugh Johnson. Mitchell Beazly Publishers Limited 1973
- Trees, Shrubs and Climbers. T. J. Kruger. Published by the author 1981.
- Bonsai in South Africa. Rudi Adam. Struik Publishers 1992.
- Bonsai Techniques II. John Yoshio Naka. Dennis Landman Publishers, Santa Monica, California.