Rooting Trichocereus sp.

[tedzr]

I think with ferts for cacti you want to go for an Nitrogen-Phosphorous-Potassium ratio of something around 1:5:1. I'm pretty sure a lot of people having read trout, would use miracle grow over growing season. It seems to work quite well in my experience, makes my bridges pup hard on hot days.

All mature actively growing cacti need to be fed occasionally. It is best to use a formula specifically designed for cactus like 7-40-6. (Nitrogen, phosphorus, potash) Use a mixture with a low ratio of nitrogen, as cacti can be burned by it. A commercial formula such as miracle grow or rapid grow can be used, but should be diluted to half strength. I have heard that "cactus juice" brand by Sudbury (1-7-6), is highly recommended. Regular Bone Meal, available at most Garden Centers, makes an excellent organic fertilizer. Don't forget the macro-nutrients like Iron (Fe), Calcium (Ca), Sulfur (S), and Magnesium (Mg). Also important are the micro-nutrients Copper (Cu), Zinc (Zn), and Manganese (Mn).

source

[CβL]

Remember though, that the advice for cacti is like saying All trees in the entire world like this one fertilizer ratio. Cacti grow from droughty (it's actually a real word lol) deserts, to rocky fields, to cloudy mountains, to forest margins, and everywhere in between (and even some native in Canada!). So basically, they are all different to varying degrees. I think that most advice for "cacti" tends to focus on the desert types. Trichocereus (at least most of the smaller spined varieties), grow in the mountains and thus have ready access to water and rock nutrients. They also live in soil usually, and thus also have access to a fair amount of nitrogen. So, essentially, don't be so worried about the nutrient content for Trichocerei. They are not as fussy as say, a Tephrocactus.

In saying that, I do believe that there are range limits where your fertilizer will elicit differing behaviour from your Trichocereus plant. I for example, have noticed that excess lime seemed to attract (or at least enable) gastropods (slugs and snails) to feast readily on those plants. Just as strangely, the removal of the lime (usually it was for rock mulch) seemed to stem the tide of grazing.

I would like to believe there is some way to "persuade" a Trichocereus to flower (if I didn't believe it - why would I try looking for a way?). ;)

[tedzr]

True that Blunt, the above advice was specifically for T. Pachanoi. I think you are right about different types of fert doing different things for the plants too - I noticed that when using seasol and worm poo as opposed to miracle grow, the appearance of my TBM became more warped - more twisted spines and stranger growth patterns. While when using Miracle Grow in combination with hot weather it seems to promote pupping. This is all obviously anecdotal evidence and I wouldn't claim it as fact because I'm simply not sure if its just chance. A cactophile (lol) I bought my lopho off told me that eating it wouldn't do anything as the soil here doesn't contain the right sort of minerals - excuse or not, obviously there are plenty of factors that effect phenotypic expression.

[CβL]

Well I wasn't saying it was bad. I use a combination of 4:8:6 and 5:5:0 fertilizers so would be high in P (not on )

I have also heard anecdotal evidence of MiracleGro spurring pupping. I personally get very few pups from my plants (other than stem cuts which still take ages to pup). Once I overpotted a plant, and it pupped twice basally. And one of my Cuzco hybrids recently chucked a pup halfway up the base (which was a stem cut). It gets quite a bit of shade compared to the rest, so maybe that could be why.

[Seldom]

just put a 2 segment TBM that i bought back from EGA into some soil, if anyone saw it was from the basketfull they had at the HHH stall, searched through em and got a bit which would, once apon a time, have had roots, but which have since been busted off just leaving a woody nub at the bottom. i've just plonked it in a pot of fast draining fairly basic soil mix, i'm pretty sure it'll take off but i've got no exp. with TBM. is there anything else i should be doing?

[tedzr]

just put a 2 segment TBM that i bought back from EGA into some soil, if anyone saw it was from the basketfull they had at the HHH stall, searched through em and got a bit which would, once apon a time, have had roots, but which have since been busted off just leaving a woody nub at the bottom. i've just plonked it in a pot of fast draining fairly basic soil mix, i'm pretty sure it'll take off but i've got no exp. with TBM. is there anything else i should be doing?

 

Sounds good to me - they love sun and water. Wait a few weeks until the cut is rooted and give it a good soaking Species type is prone to black spots, but they come and go in my experience, best not to worry about it, it's just a little case of the herp.