T. Bridgesii Seedlings... Hybrid or Not Hybrid

[Optimystic]

I got these as seedlings a little less than a year ago (the 3 larger ones)... all they have done is change color since then... I may have tricked them into dormancy by mistake by trying to grow them under fluoros at first, though they have had decent window sunlight for months now... Finally they greened up a bit with a dose of Kelp just recently

The one in the middle in the first pic, I think is obviously a Bridge... the two on the left and right show alot more spines but definitely scream bridgesii with the mean long spines... I saw in another thread where someone was talking about the signature of a bridgesii hybrid, but I havent run across that post again... and so I'm wondering if anyone else believes those 2 are possibly hybrids?... they both have 7 ribs, whereas the one in the middle has 6... also the spines are way darker than the middle one, more of a reddish brown... These are approaching 3 years old as a rough estimate...

Also, the one in the light green pot, was gifted to me with another purchase from someone else... But he never responded to tell me who the parents are!!!! It screams bridgesii to me as well but looks a bit different... this one has 6 ribs, 3-5 reddish brown spines per aereole and a nice rich darker green flesh... Has been growing like a champ...

So im interested in opinions and/or informed experience with bridgesii seedlings and hybrids... but any comments are always welcome on anything I post

Hybrid? Not Hybrids? Too Early to tell?

Thanks a bunch

[nitrogen]

Look like bridgesii to me - all of them. Could be hybrids though with bridgesii dominant - really hard to say - if the bridgesii was the mother and the father a pachanoi or whatever, the offspring could look very bridgesii indeed..

[CβL]

The front 3 look bridgesii (so far), and the back one it's a bit too hard to see clearly, but it looks like it's at least part bridgesii - if not all bridgesii. They'll change a lot once they green up, start making wax, and get fat. I would basically say it's too early to be certain (not that it's ever possible to be certain with these plants ). But the main defining trait of a straight-bridgesii (IMO), is the spines appearing randomly oriented - which is what we're seeing here.

Those ones there do need some care - namely extra light, and nutrients. The other plants in the photo are doing good (also they seem a bit low on light possibly, as they could be fatter definitely), so if the soil mix is the same with these bridgesiis they just need time and light, and perhaps some liquid ferts to get up to speed to reach the reserves of solid ferts.

[Optimystic]

Thanks for the input! Both you guys! They are genuinely some of my favorites in my collection and thus the name "Spine Collector"

No doubt these have strong if not complete bridgesii influence... and Im well aware that there is alot of variation among bridgesii seedlings...

Unfortunately its hard to see but the ones with longer spines had some knocked off and bent in the process of shipping, especially towards the top where they had just begun to get long... I want to say the spines have grown a little but I am just not sure, even after staring at their early pics for a while... Theres spots where I think some would have been longer spines but maybe were catching shade or something... @ CBL thats what my struggle is with these two that I really think the spines seem quite uniform and the aereoles are a little more "feltier" It doesn't bother me either way, and frankly I just started wondering about them after looking at them for months.... If anything im anxious for them to grow ... obviously this hobby hasn't cured me completely from my lack of patience lol

I know they are ready for more light, and frankly im sure they were acclimated to sun before I got them, and that could be the entire issue with growth here... Recently I added a mylar strip the other side of my window seedling spot so they get more coverage and it seems to be encouraging more growth on my smaller ones... These 3 were some of my earlier seedlings and I had to learn.. thankfully they didn't etoliate cause they are some beauties ;)The plan is to pot them up into larger terra cotta pots in the next few weeks and get them acclimated the way they like it.. but also Im gonna continue to foliar feed them until then.. its fairly warm where they are but the short daylight hours are just beginning to increase as we approach spring here... They have been fed about 2-3x monthly fed 1/3 to 1/2 strenght schultz cactus drops on top of being in the same mix I used for everything thus far which is enriched soil... I added a little worm casting tea a while back but the kelp was the first to make any change, but it could also be season related.... Im switching soils this year and havent figured out what yet, but it sucks cause the only thing available here in terms of cactus mix is peat based.. and so im gonna have to repot alot of plants this year and next, and get a little creative

Anyhow, its getting close to spring and with them showing a little promise of a growth spurt im getting a little excited @ how much more redundant can I get haha

Edited January 20, 2013 by Spine Collector

[CβL]

Once my plants hit about 1 inch (2.5cm) high (actually sooner, but I keep a careful eye on them), I don't really hold back, and they're put outside to face the elements. I think your plants can be put straight into a spot where they will get mostly-sun straight away (as long as major frosts are over) - then just keep an eye on them to see how they handle it. They're really tough, and it's harder to kill them than to keep them alive.

I don't know how long they've been in those pots, but there's no need to pot them up to anything bigger if they haven't been in them long. As a rule of thumb - squeeze the base of the pot (if it's plastic), and if you can compress the pot with your hands, then the plant can still grow. Only once you cannot compress the pot, do you need to repot (this is the point the roots are holding everything tightly). My other rule of thumb, is that I expect about the same volume of growth from a cactus, as there is new soil in it's pot. If I really want to push the cactus - I let it grow until I see the base getting sucked in (if the cactus has been getting enough water, then this means the plant is recycling itself for phosphorus) or until the new growth is very pale (a sign of low nitrogen) - but pushing the cactus in the same pot past these points, doesn't seem to be healthy for them.
I would be careful to not feed them too much unless they're actively growing - as the nutrients build up in the soil, and can burn the plants roots (this is I think actually caused by excess osmotic pressure causing the membranes to rupture - my hypothesis). I think what you're feeding them is pretty safe though, as long as they're getting water in between liquid fertilizations (I think the plants like to experience differing concentrations of nutrients, rather than always the same concentration).
Lastly, a very peaty mix is fine for Trichocereus, and I think they actually prefer it over sandy/rocky soils.

[Optimystic]

That all sounds like excellent advice... Since these are a little bigger than my other seedlings I wanted to give them a little more lateral space (not too much) for the roots.. I don't think this is exactly the problem but when they take off I want them as much room as they need... I have a dozen smaller bridgesiis a year younger, and 4 of them are in smaller pots with restricted lateral space... the result is that the ones in the slightly bigger pots have outpaced the others by an inch or two and thus I want to give a little more lateral space to the bigger ones... I potted them with what I had at the time but i've come into a over 100 clay pots of all sizes since then for really cheap and im transitioning all my plants over... since these haven't grown at all, in an entire year, I want to start them off right... plus my bridgesiis in general seem to like to dry out more and that will help ensure that I think, thought Im not sure it would make much difference since they are small pots...

Most of my plants are doing quite well in the peat based soil.. but I think its around a year or two the peat begins to break down and can give an acidic ph.. in fact peat moss is recommended for my blueberry plants as an alternative to other ways of acidifying the soil... and everywhere I read says this can lead to nutrient uptake problems later on.... but If I recall correctly I think they add a little lime to the mix, not sure ... I know the same brand has a garden cactus mix (not potting mix) and that says advertises added lime, while the other ingredients are identical... with that said, I realize triches are quite adaptive, more so than other cacti species, but I want to make them feel as close to home as possible

but you have an excellent point @ overfertilizing and I've been going with very light doses just to be safe... but also I want to repot just to check roots and I may as well go with terra cotta meanwhile so I can keep my plants on the same feeding schedule... its really easy to lose track of plants when you have a bunch and plus im not limited to just one species so its been a task... its becoming quite full time lol

They are approaching an entire year with zero growth... just got dull colored and greened back up... thats my thinking on just changing everything while simultaneously checking the roots

Edited January 20, 2013 by Spine Collector