Growing Dragon fruit in Heathmont, Melbourne

I'd like to welcome Adam from Heathmont in the eastern suburbs of Melbourne.
He is newish to growing dragon fruit but is doing an amazing job, spouting dragon fruit cuttings over winter. He uses a water technique I haven't scene before he contacted me. Please read on to find out more. 
What suburb and state are you located?
Heathmont in the eastern suburbs of Melbourne. We get about 800 mm of rain per year. The average temp in winter is 14/6 degrees max/min. The average temp in summer is 27/14 degrees max/min. Some days get up to 40 degrees in summer, and we get about 5 days of frost per year. The soil type is heavy clay and in winter it is perpetually soggy and wet.
How long have you been an avid gardener for?
I'm just a backyard gardener, on and off for 10 years.
What is your history with gardening and horticulture?
My main hobby is growing edibles.
What drew you to Dragon fruit?
The way the dragon fruit grow on a succulent, and the flowers that only open at night make them very intriguing. 
Can you please walk me through your history with dragon fruit?
I am a beginner, and have only just started growing them.
What was your 1st dragon fruit experience eating?
Dragon fruit are not something commonly found in the shops in Melbourne. We went on a holiday to QLD 6 months ago, and myself and the kids tried dragon fruit for the first time. The kids really liked them, so I decided to see if they can grow in a Melbourne climate.
Growing dragon cuttings fruit in Melbourne
What was your 1st dragon fruit experience growing?
I obtained some cuttings 6 months ago, at the start of Melbourne winter. After rooting them on a heat mat, I planted them in pots and kept them indoors next to a sunny window, and they are all taking off now that it is spring.
Growing dragon fruit in cold climates
What is your Favorite variety and why?
So far I've only had the chance to try the generic white and red varieties, and the red one tasted sweeter.
Best tip for growing dragon fruit. Biggest no, no for growing dragon fruit.
Early days for me, so I haven't got any tips yet!Growing dragon fruit cuttings in Melbourne
Biggest challenge for growing dragon fruit you have had?
For rooting the cuttings, I immersed the bases in water. After 2 weeks they failed to root because it was still too cold even indoors. I then placed a seedling heat mat underneath them, and voila, they sprouted roots very quickly. So it seems like they prefer temperatures >24 degrees to grow roots. On some cuttings I exposed the cambium layer using a V-shaped cut, which improved the rate of root growth.
This technique was learned from YouTube 


Growing dragon fruit cuttings with grafting paint
How do you fertilize?
I am planning to use diluted worm juice.
How many varieties do you currently have?
11 cuttings of different varieties. I want to see which ones do best in the extreme summers and winters that Melbourne has.
Scotts Purple Hylocereus polyrhizus x -watermelon flavoured
Delight- H. undatus X H. guatemalensis California 
Halley’s Comet (XXL bloom)- H. undatus X H. guatemalensis Louisiana 
Isis Gold - Hylocereus Undatus X QLD Australian Dragon Fruit Variety 
Condor- Hylocereus guatemalensis X Californian Dragon Fruit 
Pink Panther (XL bloom)- Hylocereus guatemalensis X Californian Dragon Fruit 
Sugar Dragon (S8) - Hylocereus Hybrid Californian Dragon Fruit 
American Beauty- H. guatemalensis X H. Undatus USA Dragon Fruit Plant
CFA Desert King
Colombian Yellow
Growing dragon fruit in Victoria
What soil did you pot your cutting in?
I have planted them in a mix of premium potting mix + perlite.