Help; can I save my T. spachianus?

[Asclepiad Stevo]

Hello,
Can anyone advise me on the condition that has worsened on my Trichocereus over two seasons. I at first just thought it was 'corking' as occurs with cerei with age, but this isn't that.
Much appreciated,
Steve

[Peter]

I'd chop it off higher than the marking, leave it on the bench for a couple of weeks to dry then pop it into dry compost for the Winter. It should be throwing out roots by the Spring.

[lobman]

Looks a bit like a reaction to winter cold to me , although it should be OK down a degree or so lower than zero .
I would indeed chop it off and re establish in part because the base looks too small and restricted to take the strain as the plant gets larger and becomes heavy .
keep the stump as A. it is security if the top fails for some reason . B . it will produce more offsets .

[topsy]

HI Stevo,

I would go along with the comments already made, but I would delay chopping the base off the plant until the spring as any cut surface at this time of the year will not dry out very quickly and may attract molds. It does not look as though the damage is rotten, it looks dry, so unless we have a really cold winter again it is unlikely to become further damaged. I don't know how tall your plant is but assume it is fairly tall. in which case once the cutting is taken you will need to keep it upright by propping it against something otherwise it will tend to go banana shaped and become difficult to keep in a pot for re-rooting.

If at the end of the winter the damage has not spread further, I would be inclined to keep the plant without cutting it. Re-pot it, placing it a bit deeper in the new pot than the soil level is at present and covering the rest or most of the remaining problem area with top dressing.

I notice that your plant is standing outside, where do you keep it for the winter?

Good luck, Suzanne Mace

[MikeT]

Steve

Looks like scarring not rot. If it's soft, then it's rot and needs surgery now. If it's hard (which is what I would guess, from the picture), then there's no urgency; you don't have to resort to surgery, but it would get rid of the scarred area, give you a clean plant, plus offsets from the stump.

Unless there is rot, I'd go along with Suzanne's timing and wait till spring. The cutting will root much faster then. As Peter has said, leave the cutting for a couple of weeks to 'callus' (dry out) before putting on compost.

[Asclepiad Stevo]

Hi, thanks for all your advice. I'm thinking that the idea of a re-pot in spring and submerging the affected area is the way. It isn't rot, so will use perlite/loam around collar. Is there a method to produce rooting from the area newly submerged? Cutting a 5mm 'gob' cut, or wedge around the circumference, allowing to callus then potting? I feel loathed to lop and 'start again' as I lost 6 Notocactus buiningii offsets (parent plant suffered trauma) all failed to root.
Kind regards, Steve

[lobman]

In the Spring , I would plant it in a larger , wider pot , to help with balance , but not plant it much deeper as this could indeed induce rotting . The marks on the stem could be hidden by using something like 20mm gravel as a top dressing --- I think that you will find that the slim base of the plant is able to keep the top growing just fine , and can still expand with time even with the corky marks