Starling's definitive guide to growing and harvesting dragonfruit

[starling]

About 'Dragonfruit'

The term 'dragonfruit' refers to any number and variety of selenicereus and hylcoereus members of the cactacea family. These plants naturally occur in the Americas--particularly in the North. and central regions, especially but not limited to rainforest type settings. Elevation does not seem be a decisive factor in natural distribution as they occur in coastal and mountainous regions. Hyle is the greek root for 'forest'--which is a clue to the types of locations dragonfruit traditionally grow in. They are essentially a forest, or jungle cactus, with requirements virtually completely opposite to their arid-loving cousins. A dragonfruit given the kinds of conditions preferenced by an Opuntia, for example, will die--and vice versa.

Although the selincereus and Hylocereus generi are diverse,there are really only a small number of variants of dragonfruit which are commercially produced; hylocereus Undatus, H.Polyrhizus, H. Costaricensis, H. Guatamalensis, and Selenicereus megalanthus. Crossing and hybridization however is extremely diversified, and given that dragonfruit will readily hybridize with just about anything from the cereus genus as well as with epiphyllums, it's almost impossible to know where the boundaries end with particular cultivars ( a friend of mine just succesfully crossed a dragon with a peruvianus, for example). Dragonfruit flowers are not naturally especially colourful and vibrant, being mostly bone white, yet many of the American Cultivars display extravagant and brightly colored blooms very similar to those of fancy epiphyllums. It is almost certainly the case that these types have picked up epi genes, or those from columnar cereus cacti, somewhere along the way.

Soil

Dragonfruit require very free draining soil with a PH from between 4-5.5 that does not cloy, become gluggy or dry out. It should be rich in organic matter, low on nitrogen. high in calcium and potassium. For a failproof soil mix, you can use high quality premium potting mix, cow manure, sand, and a little coco coir at the following ratios:

4 parts potting mix

2 parts washed river sand

2parts composted cow manure

2 parts coco coir

If you want to get fancy, save your eggshells and blend these in with your mixe, crushed--this will give you great drainage, and your plant will love the calcium.

Planting

Very few people can get away with planting dragonfruit directly into unamended substrates and get good yields. If you think your soil isn't good enough, it probably isn't so don't bother trying because you will more than likely end up with a gigantic vine that doesn't fruit. Having over forty something different CV;s, I do not have a single variety in situ.

The good news is thus; dragonfruit are perfect for container growth, as they have very shallow, fibrous root systems. Any pot 65L and up is large enough to grow out a plant to full fruiting maturity. Generally, what I do it buy a large faux terracota yates pot, cut the bottom out, and fill to about 2 inches from the top with my mix.

The main cause of premature death in planting dragons is collar rot. It is extremely important to plant your dragonfruit cutting at quite a shallow depth--I recommend 1.5-2 inches maximum. Just enough so that the plant is able to remain stable, vertically. They do also, I have found, respond very well to seaweed root boosting treatments as well as mycorhizae treatments.

Edit: I do not know why this is, but a cutting taken from a rooted plant will grow faster than the rooted plant it was taken from, every time. The difference will be quite dramatic. Go figure.

When selecting a planting position, you want to give the plant as much sun as you can possibly give it--at least six hours and up. Dragonfruit are aggressive negative phototropes--that is, they grow towards the shade. This is because in their natural settings, the grow up the trunks of trees before bursting through the canopies to receive pure, hard light--this is their que to fruit. If you don't give your dragonfruit full sun, it will either fruit very sparsely or never at all. Don't plant your dragonfruit close to a shaded area, because it will try (forever) to grow into the shade. and you will get a seriously lopsided plant by the end. Every single dragonfruit farm in existence has rows of plants staked out in full, baking sun. Here's an undatus hybrid I planted too close to an undercover area (bottom left)--notice the lopsided growth as the plant reaches for the shade.

Fertilization

In the off season ( temperate months) you will need to use a nitrogen-free cactus fertlizer that is high in calcium and potassium. Do not use nitrogen based fertilizers at all out of season. As you approach the season, start a regime every couple of weeks of weak nitrogen based fertilizer and TE's. Powerfeed at half strength is good for the task, or a couple of handfulls of rooster booster. A lot of growers opt for the chicken poop citing its similarity to bird guano, which the plants would receive in large doses during fruiting season in the wild. This makes sense to me.

Watering

You must never either let your soil become sodden, or dry out. Taper of watering when buds are forming--an inundation at time of flowering will cause your flowers to abort. I don't know why this is, it is just what I have observed. You want moist--not wet, fertile soil.

Pollination

Hand pollination will increase both yields and fruit size, and not only dragons are self-pollinating. You should never plant out a single unique variety for this reason--plant two different types on any one trellis.

About Aerial Roots

Dragonfruit, although displaying epiphytic behavior, are not true epiphytes. The role that aerial roots play in the overall nutrition of the plant is thought to be minimal for this reason. Although the do derive some nutrition from bark etc naturally, the consensus seems to be that aerial roots primarily function as a survival mechanism in the instance that the plant is somehow severed at the soil level. I have personally observed this--have seen a gigantic gum tree being absolutely smothered by a feral dragon in a local park. The council cut it away at the base of the stems in several places, but it just sent new growth back down from 20 plus feet up the tree which re-rooted in the soil. The aerial roots on this monster would have been as thick as my arm.

Do not ever plant a dragonfruit against a tree. It will go completely rampant. Because the plant itself is so heavy, it will also snap off enormous limbs, especially during storms. Also, the fruit will be too high for you to reach and will become bat and possum food.

Edit: You do not need to wrap your trellis post in burlap--this is both unnecessary and will achieve nothing at all. The aerial roots will cling to anything--even poly pipe.

How do I know when to pick?

Your dragonfruit are ready to harvest when they are fully and vibrantly coloured, the flower hanging out the end is completely dead, dry, and brittle, and the fruit yield slightly to your touch. Picking too early is better than picking too late; over ripe dragonfruit develop a strange, turpy-bitter taste that is, quite simply, as nasty as shit. They will not ripen well once picked in the way that tomatoes will ripen on a windowsill in sunlight.

Trellising

No matter which way you slice it, you are going to need to build yourself a good, sturdy trellis upon which to grow your dragonfruit. Designs are abundant and often as kooky as they are varied. There are a few essential requirements your trellis will need to meet in order to function well:

A) It must be able to bear a load of at least 200kg. What this means, effectively, is that for a standard 8FT post, you are going to want to have your trellis concreted into the ground at a depth of three feet, with 5 feet of your post proud of the surface.

You must select a full sun position--that is, a spot that will give your plant at least 6 hours of direct light per day

C) If using wood, you will need to use a treated kind. Pine is actually longer lasting than hardwood, because all the nasty shit used to treat it penetrates into further into the grain.

D) must have a crossbeam, crown, or some other type structure at the top over which the plant can grow over and cascade downwards from.

A fence will work--but your neighbors will get most of your fruit. It's also difficult to make the plant grow up a flat vertical surface in a way that you're happy with. They are not really like, say, a passionfruit--the shoots are heavy, and will often snap if not supported, putting you back months or even years.

My trellis design

is a tension based system cobbled together from cheap materials that is pretty easy to build. It has since been copied and improved upon. It contains no parts that can rust, break, warp or decay. Here's how I make one, and a picture of the finished product.

Materials and tools:

1x hand swager

1xbag of swaging grommets. You will need 16 in total--I'm doubling the actual required number of eight, because you will get it wrong a few times, probably.

1x length of 8ft stormwater downpipe--as large or small diameter as you prefer

1x7/12ft length of rebar--note, you can throw any steel down there, really. But rebar if you have it, it's the best.

1x bag of cement

1xbag of rapid set cocncrete

1xbag of washed river sand

1x aluminum or carbon fiber bicycle Tyre rim

1x roll of 3mm stainless steel wire--you can buy this for ten bucks a pop from ebay.

1x closed eye loop screw--galvanised or stainless.

1x65L pot and up--there's no too large.

1x pair of wire cutters (if hand swager doesn't have them built in)

Directions

Dig a hole three feet deep, and place in your length of rebar--you can screw it into the soil a little bit to keep it steady, that's fine. Mix a 1/4 of your bag of rapid set, and pour this around your rebar. Allow to set two hours. Make sure rebar is sitting straight, not on an angle.

When that's set. take your length of stormwater downpipe, and slip this over the rebar. Take the rest of your rapid set, mix it up, and fill in the hole around the base of your stormwater drainpipe. Allow to set two hours.

Next, you will need to take your cement and sand, and mix your fill for the post. I generally mix three parts sand to one part cement, but feel free to tweak this. The main thing is to get a consistency that's easy enough to pour down the pipe, but still as muddy as you can get it. Just slowly add more water until you get there.

This next step takes a little bit of timing. What you're going to do is take your closed eye loop bolt, and gently insert this into the top of your stormwater pipe, sinking it up to the loop. Now, as I say--this takes a bit of timing. You want to do it before the concrete has set, but not so soon that the bolt just sinks straight to the bottom of the pipe. An easy trick is to keep a grip on the bolt, and to test the viscosity of the concrete by gently driving down the bolt--if you get some resistance, you're good to go. If it wants to just sink, you need more time. It's a little bit finicky, but it's really not that bad--you'll be able to gauge when its ready when you're doing this, I promise.

Once you've got the bolt in, and the concrete everywhere is set, you are ready to slip over your pot. To do this, you will need to cut out the bottom. Scissors will do the job if you do not have a grinder or reciprocating saw. Start a cutting point with a drill by just drilling into the bottom of the pot and moving the bit while drilling from side to side slightly. Do this towards the outer edge of the pot so as to create as large a hole as possible--but not too close to the wall of the pot--you don't want to crack the sides!

As stated previously, I use the yates faux terracotta pots. but I also use the crappy, cheapo rubbery feeling storage tub thingies that bunnings sells also. The downside of this is that they are not UV treated and will decay in a few years, and will need to be cut away. I don't recommend these for this reason--I only use them because I intend to build a raised bed around all my elite dragons when the tubs need to be replaced, which are all planted in a line. Don't skimp on the pot. Buy a good one.

Once you have cut the bottom from your pot, simply slip it over the top of your pipe. Look around you--there will be soil from the hole you've dug. Get this, and spread it around under the base of your pot, and tamp it down so that you pot has a level surface to sit on.

Next, it's time to build the crown, and allow me to note:

Don't forget to put down the pot before you put in the crown, otherwise the whole exercise will be a waste of time. You will NEVER--I REPEAT--NEVER get the pot over the crown once the crown is attached.

put down the put first

put down the pot first

put down the pot first

Moving on.

What you need to do here is take lengths of your stainless wire,feed this through the loop of your bolt at the top of the post, and swage these loops off with your grommets. You will need to do four in total, and the lengths will need to be long enough so that you can do another loop at the other end of the same size. You might have to have a few goes at this--but don't fret. Ten metres of stainless wire is ten bucks. You can afford to get it wrong a few times.

When you have four lengths secured to your central bolt, it's time to start feeding the non-looped ends through the spoke holes on your bicycle rim. There will be some that are larger than the others--use those. Make new loops at the these ends, swage off with grommets, and you now have an indestructible dragonfruit trellis that has several advantages over wooden types:

A) it's impervious to weather

it will allow more of your shoots to receive more sunlight, which will mean more fruit.

C)it will increase air flow reducing fungal infections

D) it has mobility so that in high winds, less force will be applied to the post itself--this will be taken up as tension by the wire.

F) Your plant will achieve a beautiful, cascading growth pattern on maturity

G)It will space out growth allowing easier access fat harvesting time.

H) You will not get copper, arsenic and whatever else is used to treat pine accumulating in your soil.

If you want, add some electrical conduit, or just common garden hose, over the wire as I have done. This does stop the wire digging into the flesh of the plants. As you can see, I also mulch with stones. This is just my preference, as I find woody mulches tend to mess with my soil structure too much over time, stones hold in moisture more effectively and allow liquid treatments and ferts to pass through more easily. This is my latest grove, and contains some of the more mature plants I have left after the 2011 floods wiped my advanced collection virtually out of existence, and I began re-collecting a couple of years back.

Thanks for reading!

s

Edited January 30, 2016 by starling

[manic]

Very nice starlling, I have been growing a number of dragon fruit plants now in the Adelaide Hills, we cop pretty wet cold winters and amazingly the ones outside the greenhouse a doing the best! Very interesting read thanks.

[BedOSpines]

This will come in handy

[Enrique sanchez]

Thank you very much for this! : )