What are Dragon Fruit?
Dragon fruit or pataya (Hylocereus sp.) are fruiting cactuses from South America. The fruit is very popular in Asia and is gaining momentum here in Australia. Dragon fruit is high in vitamin C, minerals and antioxidants and looks as though it should taste very exotic with its super bright and juicy flesh. Truth be told the dragon fruit actually tastes very mild with the yellow pitaya being slightly sweeter than the red. I love it but I am telling you this early on so as not to set unrealistic expectations.
The name dragon fruit pays homage to the colourful and scaled look of the fruit and is quite apt at describing the fruits external appearance. The plant itself is rather dull looking except when in flower (the flowers are spectacular but more on that later). The plant is a green vining cactus that grows in 2-3ft segments separated by woody stem joints. Some people like the look of the plant while others hate it. I am indifferent but must admit that my wife thinks it a rather ugly addition to the garden. If you ask me the fruit more than makes up for any shortcomings in the plants appearance!
How to Grow Dragon Fruit
Climate and Soil
The plants are adapted to a dry tropical climate and grow well in most subtropical and tropical areas. Dragon fruit can also handle brief periods of frost and so can be grown in a protected micro-climate in temperate regions. Extended periods of below freezing temperatures will kill the plant. Full sun is preferred but is not essential with plants still producing well in partial shade.
Plants need high quality soil with a good amount of organic matter and excellent drainage. If drainage is an issue on your land then mound up the soil before planting. Dragon fruit also need to be kept moist if they are to produce well. Despite appearances it must be remembered that the pitaya group are not desert cactuses and will not perform under those growing conditions.
Size and Spacing
Basically as big as you let them grow. Luckily though dragon fruit plant size is easily controlled through management.
ManagementThe dragon fruit plant is a vine and this poses unique challenges when growing the fruit for production. The plant must be grown on a trellis of some kind. I have a friend that simply grows the plant on his front fence. This works well for him and he always has plenty of fruit. Commercial growers grow their plants on hardwood,steel or concrete poles and train the plant to divide into fruiting branches at the top of this pole. This gives the plants that classic Sideshow Bob appearance that many will recognize (at least that is what I see) and plants can then be treated as individual trees as though in an orchard. The system also keeps fruit withing reach, a big plus!
In the home landscape almost anything that will support the plant can be used but it would be irresponsible of me not to give you some warnings. Dragon fruit get heavy, very heavy. They also have very strong areal roots that will pull apart a weak scaffold and work there way into any cracks where they will make them wider. A local friend who grows a few dragon fruit plants in the sideshow bob style has had to re stump his plants after the original pole collapsed. A four by four length of wood is not strong enough. My second piece of advice is to not train the plants up a tree (stumps cut at head height are excellent though). The cactus will very quickly grow to the top of the tree and most of the fruit it produces will be well out of reach. I am going to bring it up again, plants get really heavy! A dragon fruit plant that has covered a tree could be several hundred kilos and could easily bring down branches, a dangerous situation.
Dragon fruit must also be pruned but the method used depends on the structure. Plants fruit best once they have reached the top of the structure and have hung outwards and down away from it. Your aim here is just to keep the extending cactus limbs from growing so long that they become a nuisance or touch the ground/other plants. Prunings can then be potted up and given to friends or sold, assuming you have enough plants of your own of course!
FruitingThere are some important things the grower must do to get good quality fruit from dragon fruit. The first is provide adequate moisture and nutrients as mentioned above. Without it the plants will simply not produce. Once you have a healthy mature vine where the growing tips reach out and droop down from the top it should begin to flower. This drooping of the growing points seems to be a signal to fruit and often vines will not produce until this happens. Flowering can occur at any time when the weather is warm enough and the number of flowers and fruit will depend on the size of the vine. Dragon fruit flowers open mostly at night and are pollinated in their natural range by bats and moths. I have never had pollination issues here in south east Queensland, maybe some night critter likes them. It is worth mentioning that bees also pollinate the flowers before they close in the morning. If you do find that your fruit are not being pollinated then you may need to do it by hand. Simply break off the anther from one flower and use it to pollinate the stigma of other flowers (a paint brush can help). Once the flower has been successfully pollinated it will begin to form the fruit. The fruit will grow quickly and once the wings of the fruit start to wither it should be removed from the cactus, it is ripe. To remove the fruit simply twist and within a turn or two it will come free. Do not remove any fruit before it is ready as once removed the fruit will stop ripening. Fruit that falls from the plant is overripe and is best composted. Depending on the variety you may have to remove thorns after harvest. I do this with a bee brush but almost anything can be used as the spines fall very easily from ripe fruit (an old paint brush would fit the bill).
PropagationDragon fruit are very easy to propagate from either seed or cuttings. For cuttings simple cut off a section from a mature plant and stick it into a moist, well drained potting mix. Many sources say the cutting must be 1-2ft long but I use 10cm sections with no trouble at all. If done in the warmer months you will see signs of growth within two weeks or so.
To germinate the seeds simply plant them very shallowly or on the surface of a good quality potting mix and keep moist. In my climate it is difficult to stop the surface of the potting mix from drying out so I place a plastic bag over the pot to reduce evaporation. If you use the bag technique make sure that you keep it out of the sun as it would quickly get far too hot for the germinating seeds. If I am honest, I have only ever germinated seeds out of interest. Cuttings are just such an easy way to propagate dragon fruit. I don’t see germinating the seeds as being worth the time and effort unless you are attempting to grow a new variety.
There are three species of dragon fruit that are commonly grown here in Australia. There are also cultivars of each but I lack the skill and experience to know the difference most of the time.
Red-Fleshed Dragon Fruit (Hylocereus costaricensis)
The most common species here in Australia, we grow this one here at Boobook Farm. It is a red-skinned fruit with red flesh. There are small spines on the vine and no spines on the fruit.
White-Fleshed Dragon Fruit (Hylocereus undatus)
The most common species grown overseas. It is a red-skinned fruit with white flesh. To me it tastes the same as the red-fleshed dragon fruit. There are small spines on the vine and no spines on the fruit.
Yellow Dragon Fruit (Hylocereus megalanthus)
A yellow-skinned fruit with yellow flesh. This is my favourite variety (we also grow this one here at Boobook Farm) and to my taste is sweeter than the other two. Unfortunately a little more care is needed in harvesting the fruit as both the vine and fruit are quite spiky.
Pests and Diseases
I don’t get any issues with dragon fruit here and until I know more about the diseases others get I am not going to pretend that I do. There is a great dragon fruit disease resource at the Tasty Landscape website so if you are having issues be sure to check it out.