They are of widely varying sizes, most with lanceolate leaves fanning outward radially and bearing clusters of tiny flowers. The ‘Cabbage Tree’ and its variants are perhaps the most well-known and also the most popular species.
Cordyline species are fairly diverse in both size and appearance. Many Cordyline are a good choice for borders and for accents, they are used to set off brightly-coloured flowers, and they make artistic elements in a rock garden. They can be placed in the corners of your patio, and they can just as well be placed in the corners of your drawing room.
Although Cordyline comprises of 20-plus species and several hybrids and cultivars, the well-known and popular ones number six or seven, on which our write-up focusses.
Cordyline are evergreen perennials and many of them resemble miniature palm trees. The leaves tend to be lance-shaped and pointed, radiating outward, and growing in tiers on the central stem. They are among the most distinctive and striking of all leaves. While many are some shade of deep green, other species’ and cultivars’ foliage has eye-catching hues. Young leaves of some species are hot pink, others are bordered and striped with yellow and rose, still others are a chocolatey maroon.
But Cordyline is not only about its attractive foliage: in summer, most species bear panicles or other sprays of small white or light-coloured flowers. Come autumn, the panicles and sprays transform into tassels of small berries, usually red and sometimes purple.
Because Cordylines are perennials and, once planted in conditions to their liking, require very little care, they are an excellent choice for the casual gardener or the under-pressure housewife who wants to plant once, especially outdoors, and then leave his little beauties to their own devices.
Background, Origins and Varieties
As apes and hominids were coming into the ascendancy in the Miocene Epoch, the precursors of New Zealand’s Cordyline species were also coming into their own, migrating from northern regions circa 12 million years B.C. In (what we know today as) New Zealand and the surrounding islands, these species adapted and diversified according to specific conditions. Lush forests of Cordyline australis, Cordyline indivisa, and Cordyline obtecta covered vast swaths of New Zealand before she was settled by immigrants from Europe and land was cleared for agriculture and settlements.
Although Cordyline as a genus is native to Eastern Australia, New Zealand, and the Melanesian Islands, popular ornamental species, and also hybrids and cultivars, are found the world over in parks, gardens, and homes.
Among these is Cordyline australis aka the Cabbage Tree. One may consider it the ‘flagship Cordyline.’ Cultivated Cordyline australis frequently grow to 9 metres and in its native habitat in the wild, some trees have grown to 20 metres. This tree has a proper trunk instead of a stem and its leaves could be mistaken for green scimitars. The Cabbage Tree and its cultivars are grown throughout Europe. Back home in New Zealand, it was and remains of much cultural significance to the indigenous Maori People as well as having been a source of nourishment.
Cordyline australis ‘Atropurpureum’ aka ‘Purple Cabbage Palm’ is essentially Cordyline australis with narrow leaves of a deep brownish-burgundy colour. It is used as an architectural plant both outdoors and indoors; as a houseplant it is pruned whereas outdoors it can be allowed to attain its natural height near walls or structures.
Cordyline australis ‘Red Star’ has foliage that looks very similar to that of the Purple Cabbage Palm but it grows to only about 90 centimetres making it even more suitable for indoor ornamentation.
Cordyline indivisa, the ‘Mountain Cabbage Tree,’ is perhaps the stateliest member of the Cordyline tribe. Its leaves are relatively broad and sword-shaped with a thick midrib. However, it is their blue-green colour that is the distinctive feature that isolates them from the rest of Cordyline species.
Cordyline fruticosa aka ‘Ti Plant’ is of exceptional cultural significance to the indigenous people of Australia, Melanesia, and even Polynesia where it plays a part in religious rituals, warfare, ceremonies, and such. Its rhizomes and roots serve as sources of food and drink. Blazing red young leaves, scented pale-coloured flowers, and red berries add to the attraction of this 1.5 metre plant.
Cordyline minalis aka ‘Good Luck Plant’ aka ‘Hawaiian Ti Plant’ bears leaves in a multi-layered rosette. Its cultivars are popular ornamental plants because of their dramatic foliage. The leaves display streaks and splashes of smoky and dark greens, reds, browns, orange and pink, brightening up any home or office.
Some of the popular and visually appealing cultivars include Cordyline australis ‘Sundance,’ Cordyline australis ‘Sunrise,’ and Cordyline fruticosa ‘Kiwi.’
Lesser-known Cordyline plants worth a look are Cordyline petiolaris, Cordyline congesta, and Cordyline murchisoniae.
Feeding, Care and Growing Tips
In the main Cordyline cultivars prefer moist but well-drained soil and a humid atmosphere. While you certainly should not overwater, do not allow the soil to dry out especially during summer, dry weather, or the growing season.
These plants’ preference for sun or shade varies quite widely between even related species. Cordyline australis does best in full sun to part shade but Cordyline fruticosa prefers part shade to even full shade, with indirect sunlight being best. On the other hand, Cordyline australis ‘Red Star’ is entirely indifferent to sun or shade, being content with anything from full sun to full shade. As a general rule, species and cultivars with green leaves have a greater preference for sun; in contrast, the more multi-coloured the foliage, the greater the preference for shade and indirect sunlight.
Most Cordyline plants do best in rich soil. Use a commercial organic soil or a mix comprising close to 50 percent loam with the rest being sand or chalk, and some peat or clay. The soil’s pH should be between slightly acidic to neutral; a good range is 6.0 to 7.0. Choose either a 20-10-20 or 20-20-20 fertilizer with which to fertilize Cordyline twice a month during the growing season in summer and monthly during late spring and autumn. Do not fertilize at all during winter.
Habitat and Growing Conditions
Cordyline species, as multifarious as they are, thrive in diverse conditions. Take the Cabbage Tree itself. They can grow in soil conditions ranging from low-lying swamps to rocky hillsides in New Zealand where they once covered vast tracts of land including riverine areas.
In contrast, Cordyline congesta or the Narrow-Leaved Palm Lily sprout next to rainforests and within eucalyptus forests. Other Cordylines thrive in river valleys. However, what is non-negotiable for seedlings and young plants is ample sunlight and abundant water.
Cordyline species, as tropical and sub-tropical plants, prefer warm climates. Even so, most Cordylines are right at home in distant lands like England and Japan where they are sought-after architectural plants. These evergreens are surprisingly hardy; indeed, some species and cultivars tolerate even sub-freezing temperatures. Consider: though the preferred temperature range for both Cordyline australis and Cordyline australis ‘Atropurpureum’ is 18 to 22 degrees centigrade, the former can tolerate temperatures all the way down to -7 degrees and the latter to -5 provided the plants are mature.
With respect to hardiness, the sweet spot for Cordylines is USDA zone 11. The range is from zone 8 to 13b with a little divergence and overlap between the various species and cultivars. For example, australis is hardy from zones 8 to 11, fruticosa 9 to 12, and fruticosa ‘Kiwi’ 10 to 13.
How To Shorten A Cordyline / Keep It Small
Where Cordylines are concerned, your watchword is, “Be Merciless!” And that’s because Cordylines can get out of hand and grow tall, gangly and straggly, but they are very forgiving of the knife. Simply – and mercilessly – cut back the entire plant to reduce and control its size.
Use a pair of secateurs or loppers (after cleaning the blades with diluted rubbing alcohol) to cut off one or more heads and leave about 40 centimetres of the main stem(s). Fresh growth will soon be visible, but you can help this along by applying some blood fertilizer or bone fertilizer.
Repeat the process as and when necessary and you will end up with a Cordyline whose size and shape is to your liking. However, if, after being cut back, the plant has not grown tall but has spread laterally or looks unkempt, prune it.
Do not cut off the entire head during the rainy season or in cold weather – during periods of rain or cold, the plant needs its leaves to survive.
Cordylines are very amenable to pruning – and snipping and slashing. In other words, you can aggressively shape your plant without fear of harming it.
Cut off yellowing, withered, damaged, or dead leaves with secateurs anytime.
Prune or cut back altogether any stem that is too tall, causes a loss of aesthetic balance, or which in any way detracts from the beauty of your plant.
You can cut back a stem to induce fresh new growth to appear from that spot.
If you observe multiple shoots sprouting, you can cut off all except three or four that are the strongest and biggest.
These plants may be pruned year round unless you are in a USDA zone that is at or outside the lower border for your Cordyline in which case do not prune in winter.
Where To Buy Cordyline
Cordyline species and cultivars, which were not unpopular to begin with, are now on the upswing and are even more widely available than they used to be. The well-known and popular species, such as Australis, Indivisa, ‘Atropurpureum,’ and Fruticosa, are available at both outdoor nurseries as well as online nurseries. You can buy potted plants or seeds – Cordylines grow very well and easily from seeds.
If you want one of the more unusual Cordylines, you will have to hunt around. However, as these plants propagate so readily from stem cuttings and stalk cuttings, all you need is access to the type of Cordyline you covet.
Different species propagate somewhat differently. For example, though both fruticosa and congesta propagate from cuttings, fruticosa additionally propagates from rhizome cuttings while congesta additionally propagates from seeds.
Common Diseases and Problems
Aphids, mealybugs, scale, thrips, and spider mites are the main pests and problems that Cordyline owners may need to tackle.
If your mealybug-infested Cordyline is outdoors, release beneficial insects like lacewings and Mealybug Destroyers on the plant. They prey upon mealybugs.
Aphids are a serious threat because they breed so rapidly and in such numbers that they can outrun your efforts to exterminate them. For aphid infestations apply one-percent solution of Orthene onto the infestation and surrounding foliage.
If you catch a spider mite infestation early, it may have affected only some small part of your plant. If so, cut off that part. If the entire plant is affected, it will be difficult to eliminate the mites and the wisest course may be to give up that plant. Otherwise use an insecticidal soap solution made from Safer’s soap. Dilute to specifications and spray on the infestation.
If you find your Cordyline has scales, use jets of soapy water with which to blast off the pests. Then sponge down the infested areas with soapy water. Also spray the plant with a one-percent solution of Orthene twice a week for a few weeks.
To control a localised infestation of thrips, use diluted Neem Oil or Azadirachtin, which is a Neem extract, or BotaniGard ES. For bigger or stubborn infestations, spray Spinosad once only and not on a recurring schedule. Also deploy minute pirate bugs and lacewings, the natural predators of thrips.
Frequently Asked Questions
What type of soil do Cordylines like?
Cordylines have a distinct preference for moist soil and do not do well in dry soil. Some Cordylines do well even in wet soil but it should not be waterlogged. A soil that is organically rich is best; thus, a soil with high loam or humus content is ideal. The soil pH should hover around just slightly acidic, say between 6.0 and 7.0.
How long do Cordylines live?
Cordyline australis trees in the wild have lived up to several hundred years. In very good conditions a horticultural plant can live to 50 years. Cordylines aged 20-plus years are not uncommon in established nurseries. It takes about four years for a stem cutting to attain an acceptable size and 15 to 20 years for Cordyline to develop a trunk and grow into a tree.
Are Cordylines poisonous to cats or dogs?
Plants of the Cordyline genus are one of the top ten types of plants that are most toxic to cats and dogs. In particular, Cordyline fruticosa is extremely poisonous to dogs as well as cats. Cordyline australis and the Hawaiian Ti Plant or Good Luck Plant are extremely poisonous, particularly to cats. Dogs and cats should be kept away from all species and cultivars of Cordyline.
How can you know when your Cordyline is dead?
You need to be sure that your Cordyline is dead because sometimes they play possum! If your Cordyline has lost all its leaves, continue watering and caring for it and be patient. If new shoots sprout from the trunk itself, the plant is not dead.
But if no shoots sprout from the trunk – they may or may not sprout from the soil – the plant is probably dead. If the main stem or trunk feels mushy and soft cut it back to the point where it is hard and firm. Do so only in the summer. Then keep a watch on the plant to see whether or not new shoots sprout from the remainder of the trunk.