Saturday, January 24, 2015

Notes and results from 3 years of growing Pitahaya (Dragon Fruit) in Davis, CA

The project started in early spring of 2012.  I purchased most of my initial cuttings from Linda and Gery at Elk Creek Ranch. Two cuttings came from Harvey Correia; and in the summer of 2012 I got more cuttings from Ramiro Lobo collection at UC Irvine. All cuttings were rooted in potting soil in 1 gal pots, and then replanted to larger pots as needed.  Most plants are still growing in relatively small containers, with about 1 cubic foot soil.

Pitahaya is a tropical cactus, and Davis winter frosts can easily kill plants, if they are not protected.  Many of my plants are in pots with casters; others are in pots placed on plant caddies for the ease of moving to protected location.  Below are the pictures of pots and the supporting structure. 

I move plants to the protected areas on the Thanksgiving week.  I use two pop-up greenhouses and the space under porch.  In the winter of 2013-2014, I heated these areas on multiple frosty nights as we had many of them.  This winter, 2014-2015, I only turned heaters on two nights when the temperatures dropped below 32F.  

This winter of 2014-2015 I did not cover my plants moved to the porch area, and they all seem to be fine after two nights with light frost (28-29F)

Last winter I covered this area completely and had a heater working on the most cold nights.  If I remember it right, we had few nights with 24-26F.  Here is the look of this area in the winter of 2013-1014 

This winter I'm experimenting with two Sugar Dragon (8S) plants that I left in open areas w/o any cover.  The new immature shoots look damaged by the light frosts, otherwise the plants seem to be OK. Different varieties have different degrees of frost tolerance.

The first fruit was produced in the summer of 2013 on the Physical Graffiti plant.  The fruit was small, and produced by self-pollination, as it was the only flower opened that night.  Normally, Physical Graffiti needs another variety to be successfully pollinated.  This fruit was the size of the Sugar Dragon fruit, and not a typical PG fruit.  The picture is below.  This was the only fruit I got in 2013.

In the summer of 2014 I harvested 12 fruits from the following varieties:

number of fruits
Sugar Dragon - 8S 
Halley Comet
Physical Graffiti

No systematic weight measurements were taken this summer, but a number of pictures with the fruits on scales were taken.  They all are below. 

Halley Comet (left) and Delight fruits

Sugar Dragon (8S) fruit

Below are Delight (the largest), Physical Graffiti, and Sugar Dragon (the smallest)
The same fruits, cut in half

And here is the weight for some of the fruits in grams.
Delight, 668 gr

Physical Graffiti, 515 gr

Sugar Dragon, 109 gr

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