Denmoza Rhodacantha

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cactuspip
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Denmoza Rhodacantha

Post by cactuspip »

I have 2 seed grown D. Rhodacantha. They are now about 6-7 inches in diameter and are growing well.

So far neither of them have shown any inclination to produce flowers.

Anybody have any suggestions what I should do to promote flowering?
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Rayc11
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Re: Denmoza Rhodacantha

Post by Rayc11 »

My seed grown specimen started flowering when it was about 4in in diameter and about 6in tall, now 10 years on it's 5in diameter and 12in tall and flowers every year. The plant is grown under full sun and normal watering with a winter minimum temperature of 4ºC - 5ºC. They do seem to need plenty of light. This is it budding up earlier in the year:-
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DaveW
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Re: Denmoza Rhodacantha

Post by DaveW »

I was given the smaller seed grown one below by a friend which flowered that year, but so far not again. Probably needs to be larger before it does it again.
Denmoza.jpg
They can be quite big plants in habitat 1.5m - 3m high. Therefore as with many large growing cacti what size they need to be before flowering can be erratic, some like mine being more precocious than others. I was given a couple more out of the same batch of seed and neither of them have shown any signs of flowering.

http://www.cactusinhabitat.org/index.ph ... id=36&l=en

Most Denmoza's are red spined and I don't think there is any significant difference between D erythrocephala and D. rhodacantha.

"The genus Denmoza comprises only one species. The plants described as Pilocereus erythrocephalus and later transferred to Denmoza has sometimes, for instance by Backeberg, been considered as another species of the genus. D. rhodacantha changes considerably in the habit with age. The description of D. rhodacantha refers to young plants having strong spines in areoles. Old plants of the same species with multiple number of spines and sometimes with thin, 6 cm long bristly spines correspond to the description of D. erythrosepala."

http://www.cactus-art.biz/schede/DENMOZ ... ephala.htm

Strangely I saw the same thing with Eriosyce sensu stricto in Chile being dimorphic . The young plants are strongly spined, but spines on older plants become thinner and more bristly as they age.

There is however a yellow spined form of Denmoza.

http://www.llifle.com/Encyclopedia/CACT ... diamantina
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Peter
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Re: Denmoza Rhodacantha

Post by Peter »

Plenty of variation in Denmozas - but what great plants! All the following are Denmozas.
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Tina
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Re: Denmoza Rhodacantha

Post by Tina »

They are tough, mine survived last winter in the garden in a raised bed.
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