Maximum Yield Australia/New Zealand 2020 September/October | Page 46

Seedling dragon fruit plant raised from seed collected from mature fruit.
Young dragon fruit plants grown in a free-draining scoria-based
hydroponic substrate.
If cutting material can be obtained from a suitable cultivar,
it’s a more rapid method of establishing a crop. Dragon fruit
plants produce a large number of side shoots that can be
removed and used for propagation. Well-hardened cutting
material of at least 2.5 centimetres or longer is sliced from the
parent plant and the cut surface allowed to cure and callus
for a week before planting out. This process helps to prevent
rotting during the root formation stage. Cuttings are then
placed into a free-draining, sterile rooting medium and left
under warm, shaded conditions or on a heated propagation
bed until new roots have formed.
Hydroponic Production
Dragon fruit plants can be grown in a containerised system
and respond well to the controlled irrigation of hydroponic
systems. Since at fruiting the long-lived plants are large and
require support, a suitable root volume needs to be provided.
Dutch bucket systems or containers with at least 30 cm of
depth are suitable for young plants. At the time of planting
out, a stake or support needs to be installed for the young
plant to climb. The main stem should be pinched out at the
top once it reaches the height of the support post. After this,
three to four branches will grow and extend outwards. These
will bear the first fruit of the plant. Branches need to
be guided to grow downwards and have the tips
pruned out when they reach almost a metre in
length. This helps restrict the height of the plants
by preventing unpruned stems growing upwards
indefinitely and maintains a more productive
and compact plant shape.
Drainage is essential with dragon fruit plants, with
substrates such as expanded clay, gravel, and coarse perlite
being mediums that help prevent over-saturation of the root
zone. Drip irrigation of nutrient solution in either an open or
closed system is suitable and helps to maintain aeration around
the roots. While dragon fruit require a similar amount of water
under warm growing conditions as mature tomato or cucumber
plants, this needs to be applied in small but frequent amounts
as the root system is quite shallow and fibrous.
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Maximum Yield