Category: Intergeneric hybrids

Back in October, I posted about my attempt to pollinate my Rat’s Tail cactus (Aporocactus flagelliformis; Disocactus flagelliformis) with San Pedro (Trichocereus pachanoi) pollen – see Disocactus flagelliformis (Rattail Cactus).

I’m happy to say that there appears to have been a successful pollination and a fruit is now developing. I’ve since learnt a few things about previous hybridization attempts with Aporocactus and Trichocereus. Thanks to Patrick Noll over at Trichocereus.net for the new information.

Gräsers Schönste is an Aporocandicans (Aporocactus flagelliformis x Trichocereus candicans) x Schigra (Trichocereus schickendantzii x Echinopsis eyriesii v. grandiflora). The original article simply states that Echinopsis cv. Gräser’s Schönste is an intergeneric hybrid between Disocactus flagelliformis and Echinopsis candicans (Trichocereus candicans).

I did a bit more research and found an article, Zwei schöne Hybriden (Two beautiful hybrids) by Robert Gräser, in Kakteen Und Andere Sukkulenten, September 1957. I translated the article with Google Translate, producing a relatively readable English version. It has some useful information.

Key points:

• Flagelliformis fruits take more than a year to mature. This was the most surprising thing!
• Most of the fruits had poorly developed, light brown seeds, which didn’t germinate.
• He had only one success from Trichocereus candicans and Trichocereus schickendantzii pollen – the Trichocereus candicans cross.
• Seedlings were grafted to Opuntia. Initially, they looked like flagelliformis seedlings, but later looked more like candicans.
• In the third year, the grafted cactus flowered.
• The flower color was a beautiful, hard-to-describe red. In the English Horticultural Society’s Color Atlas, the color is referred to as “Delft Pink.” The largest petals were slightly wavy with narrow stripes in darker red on the edge. The stamens were also red, in contrast to those of the candicans flower. The flower was devoid of pollen, but was capable of producing germinable seeds, such as pollination with pollen from other Trichocereus species.

So, my chances of success appear to be slim, and it might take several years of pollinating flowers to get a fruit with viable seeds. The good thing is, there appears to be enough evidence that this is not an impossible goal, but it will require patience and perseverance.

Edit 18 December 2019: I came across an interesting article, Gräsers Vermächtnis: a hybrid of an extraordinary parentage, which has colour photos and additional information about this intergeneric hybrid.