How to repot this bruiser of a cactus so it doesn't lean

[Aridane]

I have posted before about this bruiser of a cactus which Nanthewiser identified as a (very etiolated) Ferocactus, and possibly F. hamatacanthus,

I grew it from seed as a child and it is now 40 years old and 2' feet tall. I weighed it just now and it is 10lbs!!

Anyhow, with its sheer weight, it is now tilting quite dramatically

Sorry, no clue. I would have thought a bigger pot would give it more space to create a larger root system for support though.

I'm mainly here to say that I misread your title as, 'How to report this bruiser of a cactus so it doesn't learn?'.

It's not rotten or reaching g to the light as I rotate it from time to time

Has it been a year for cacti going bonkers? We had one that started off cute, last year, but is now like a giant pack of prickly tribbles.

Ha ha - funnily enough, autocorrect initially changed it to report...

I rotate mine every fortnight and it is already leaning slightly by that stage, probably should do it weekly. It's nowhere near that size, well done OP!

I didn't know whether it needs a different type of pot altogether or whether I just need to anchor it in gravel around the base

The solid root mass takes up most of the pot

I looked on Amazon for suitable pots possibly to repot but nothing gnaws available for this size cactus

Obviously there Are outdoor ceramic, terracotta and concrete pots but they're still not really that great to showcase this thing of a cactus

I'd probably give it a bigger pot but, and I cannot stress this enough, I am not an expert.

That is one magnificent cactus.
I’m so impressed you grew it from seed and managed to keep it alive for forty years.

Do you think you just need a bigger pot or something more radical?

I don't know ☹️- google tells me cactuses like to be in a pot no much larger than itself

Plus it's an awkward shape - ie tall and heavy as fuck (10lbs - the weight of a heavy newborn) - whereas all the naice cactus pots are shallow things, designed for round cactuses rather than upright ones growing tall

I don't think I can anchor it too deep in soil as it may rot - unless maybe I bury the bottom bit in gravel?

It's a beauty! And a lovely pot too.
I think I'd be tempted to find a pot, and sink the pot into a pot of gravel or small pebbles - so dont give it any more root space, but increase the weight of the base.
What size is the current pot?

About 7" high and 8" wide

My friend is a cactus enthusiast. Her advice is:

If its leaning from the soil may need to have new pot, plant little deeper if need be to keep it stable.

Is it leaning from the soil?

Yes, it's leaning from the soil

That cactus is impressive, especially from seed. Does it ever flower? The fruit are edible, as are most cactus fruits.

My friend says from the photo the bottom doesn't look too good so she'd recommend taking it out of the pot and checking that the roots aren't rotting. She wants to know if the pot has holes on the bottom for drainage?

How about double potting? Repot into only slightly larger pot and use gravel to slightly correct tilt.
Then use a much larger container with some large interesting stones to anchor the inner pot at an angle and fully correct the tilt. Plant some air plants amongst the interesting stones (water by misting) and rotate whole pot 180°on the first of every month.

I've use three approaches:

1: let it lean, and make sure it's got something to lean against

2: repot it so that its rootball is at an angle but the cactus is vertical

3: new approach, which seems so far to be the most successful - put its pot into a larger heavy ceramic pot, so its weight is insufficient to tilt the pot over.

This isn't one of them, but there are cacti whose natural habit is to lean and then fall over. I usually provide bricks for them to fall over on so they don't knock their pot over.

Like RolytheRhino's friend, I'm a bit suspicious about the base of your cactus, Aridane. The brown colouration does look as though it could be rotting, although it can also be corking due to old age. If it's a bit soft it is rotting.
Unfortunately the tendency to lean is because it's getting a bit top heavy and also leaning to the light - always a problem when kept in a room, and not always solved by turning it.
I doubt whether you can find a larger "fancy" pot, so a bog-standard terracotta pot may be your only choice - and it shouldn't be much larger than the current one.
If you do repot, in order to protect yourself, you could use a couple of bits of polystyrene each side (if available), or padded tongs, a couple of scrubbing brushes, or bubble wrap.
If it's any consolation, I have a couple of large plants in the greenhouse that lean quite precariously, one is almost prostrate! Nothing I do makes any difference!

I don't think it's rotting as the unsightly brown stuff is rock hard. (Plus haven't watered it since January )