Evil Genius

Wish I could help, but have no idea. Could be something like Crassula.

Hey mate, these belong into the Trichocereus spachianus group. There's quite a few forms and related species that belong to it. I don't think it's the well known Trichocereus spachianus clone that's around, but it's certainly close to it. Please post flower photos when it flowers. Bye Eg

Hey mate, how long has it been since you planted them? At which temperatures did you have them. Personally, I sow out in a mix of Pumice, Lava and Coir and I wouldn't want Vermiculite in my sowing soil. It's not that it kills seeds, but there are minerals that produce much better results. Picking up seeds that were already sown out is possible, but very time consuming. I'd probably rather let everything dry out when nothing shows after 2 months and then start another wet cycle when the weather is hot.

Hey mate, send me your contact email address via pm and I'll pass it on to him. Bye Patrick

Hey mate, what browser do you use and do you use any sctiptblockers? It definitely works for me from Android mobile. Just checked. Might have to do with the browser.

Hey mate, great to see you.I'm out of competition because of import restrictions, but happy to start this off! Love this Trichocereus validus.

Hey mate, yeah, the possibilities are endless. It definitely has a Super Pedro look to it, so that one were my very first choice if I'd have to pick one.

Hey mate, welcome aboard.

Hey mate, are these different types of seedlings or species or the same? Different species have different growth rates, both in regards to the body and the roots. Then, the soil definitely looks different in structure, which could make a big difference too. Even if it's the same ingredients, their structure might be different or there might be additional add-ons in one soil that aren't visible, e.g. clay dust is often added to improve the root formation. Also, soil pH might be different, which could make rooting easier or more difficult. Position in the greenhouse/garden/environment might play a part too. A spot that's in full sun means less soil humidity and one that's more in the shade would provide more humidity in the soil. Both have effect on the roots. And yeah, nutrient availability or fertilizer composition might be different. For example, I use extracts and fertilizers containing silica because it improves the root formation dramatically. Lots of ways to look into this and hard to tell what the culprit was. Bye Eg

Lovely plant, mate!

Extreme dehydration due to unsuitable soil. The minerals you have there would probably be fine, but it lacks finer ingredients so water runs straight through it. Get some finer Pumice, Lava, Coir and stuff like that and mix it evenly. Roots can't properly form around these huge particles. They are just too loose, and it just makes it very hard for the plants to get a good root system. And ditch the quartz topping layer too. It makes it even harder to judge about the humidity of the soil because you can't check it easily. And yeah, more water and fertilizer in the future. Bye Eg

Hey mate, looks VERY PC to me too.

A greenhouse will be the death of me one day.

Yeah, Opuntia, but really hard differentiating them from just a small piece like this. They can look very similar at this size. Lovely plants though.

Hey mate, first two are Myrtillocactus geometrizans, then a Pilosocereus, then a Harrisia, next two are Myrtillocactus, then Cereus and the last one is a Myrtillocactus that has a massive scale infection. Hope this helps, bye Eg