Cycads are often lumped in with palms but are an entirely different form of plant closely related to ginkgos and conifers. Cycads may be dated back to at least 280 million years ago. Truly a prehistoric plant and one that’s growing in popularity in its own right.
Cycads have heavy trunks and are crowned by a head of large, stiff leaves. Due to their slow growth rate it’s rare to find cycads taller than a metre although older specimens can reach several metres tall and live to be hundreds of years old. They are found throughout the tropics and sub-tropics with most species originating in Central and South America, Central and East Africa and Southeast Asia through to eastern Australia. Cycad genera include; Cycas, Dioon, Encephalartos, Lepidozamia, Macrozamia and Zamia.
Lepidozamia peroffskyana is a large and relatively hardy cycad from the NSW/Queensland border. This is a fantastic and impressive cycad for landscaping in northern New Zealand. More impressive still (and sadly more tropical) is the gigantic Lepidozamia hopei from northeast Queensland.
Another Australian cycad genus suitable for New Zealand gardens is Macrozamia. There are around 40 species of Macrozamia with many from the east coast of NSW and south-eastern Queensland making them perfect for warmer parts of New Zealand. A number of Macrozamia are relatively large and perform well as landscape specimens.
Cycas revoluta is perhaps the best known cycad in the world. Capable of growing in chilly locations this is a reliable medium sized cycad that’s regularly seen in New Zealand. Two other species of Cycas gaining in popularity in New Zealand gardens are the larger and faster growing Cycas taitungensis and the tropical (but still suitable for northern New Zealand) Cycas thouarsii.
Dioon edule is a very attractive medium sized cycad from Mexico. Along with several rarer species of Dioon it is well suited to landscaping producing grey-blue to green leaves.
Encephalartos are generally large grey-blue or green cycads from South, Central and East Africa. Many are quite hardy and most are both rare in cultivation and expensive to obtain. We hope that, through commercial efforts rather than the unfortunate prohibition in trade, one day these beautiful cycads will become available to the gardener with an average budget.
As with palm trees, cycads require different growing conditions depending upon their origin. Certainly sun tolerance varies but as a general rule cycads are sun-loving plants which require mild winters (although many species will take light to moderate frost), warm to hot summers and excellent drainage. When planting or potting do ensure that there is no possibility of the cycad sitting in water. We’ve found many species to be surprisingly hardy to chills but die quickly if allowed to become waterlogged in winter.
See Garden Designs using Palms, Cycads and Subtropical Plants for more suggestions about combing palms with cycads.
The cycad genus Zamia from Mexico, the Caribbean, Central and South America contain several small cycads suitable for cultivation in warmer parts of New Zealand. Perhaps best known is the Cardboard ‘Fern’, Zamia furfuracea which, in the right spot forms a moderate sized plant.