What to do next?

[daffe]

Hei, this is my San Pedros, they are 8-10mm now and 1,5 months old. I still have them under plastic dome to have high humidity. When should i remove the dome? Should i start to give them some fertilizer? Should i repot them? How often should they have water?

[iann]

Looks like you removed the dome already? I wouldn't at six weeks, but these are fast-growing columnars and it won't hurt them too much.

[daffe]

I had to remove to take picture

[greenknight]

No rush about fertilizing unless you used a pure mineral mix that contains no nutrients at all, in which case they should be watered with a very dilute fertilizer solution. If the mix contains some nutrients, fertilize next year. Don't repot them until they've filled those cells with roots.

[cefalophone]

Typically I gradually remove my seedlings from humidity around the three to four month mark.

[greenknight]

Typically I gradually remove my seedlings from humidity around the three to four month mark.

Yes, that's about average. These are a very fast-growing species, so you can do it on the early side.

[iann]

I had to remove to take picture

Asking for trouble.

[daffe]

I had to remove to take picture

Asking for trouble.

i think its ok, i have removed the lid many times to look at them so i dont think that would be a problem, they look fine i think.

[iann]

Suit yourself. You come asking advice from people who've actually grown cactus seedlings before, but you don't have to take it ...

[adetheproducer]

I would agree, if you have already opened and closed the lid it wont make much difference now. Looking at the size of the seedlings you could even take off the cover completely. Once I have germinated the seedlings I now uncover pretty quickly, I find I get far more survivors that way with our damp welsh weather just make sure the soil does not completely dry out between waterings and maybe use a lamp for extra heat/light. Everyone's method of seedling production is different and don't worry that what you are doing is different to what others do there are no laws to this just do what works. There are a lot of people who subscribe to the baggy method and will defend it to the core but no one covers them in plastic bags in the wild. I just use a propagator tray in my home made light box to start germination, once they have germinated and grown a little I remove the plastic cover. I find I can manage the moisture levels better that way watering more if needed or leaving them dry if not. Wait until they are bigger before re-potting. The quick growing echinopsis like these can take more organic and damp soils in the short term but once they are say the size of your finger re-pot to a much more freely draining soil mix with crushed rocks, grit, stones making up say 80% of the mix. The grit and stones make the roots stronger which is what you will really be aiming for.

[7george]

There are a lot of people who subscribe to the baggy method and will defend it to the core but no one covers them in plastic bags in the wild.

The surviving rate in the wild is less than 1% generally, but we would like to get much more. I agree that natural survivors are the strongest ones. I open my wet bags with seedlings gradually (first just unsealing it, after a week cutting top plastic part and so on...) and even this way they usually get stressed and stop growing for a month until been adapted. But my home atmosphere is extremely dry.

[daffe]

Suit yourself. You come asking advice from people who've actually grown cactus seedlings before, but you don't have to take it ...

sorry for stepping on your toes. BUT, if the lid is removed and replaced in lets say 1 min. how could that affect the cactus at all? Give me a good explanation please. Its not like the cactus dry up as soon the humidity is down a min ot two when the lid is off, when its back in place the humidity is high again.

[daffe]

I would agree, if you have already opened and closed the lid it wont make much difference now. Looking at the size of the seedlings you could even take off the cover completely. Once I have germinated the seedlings I now uncover pretty quickly, I find I get far more survivors that way with our damp welsh weather just make sure the soil does not completely dry out between waterings and maybe use a lamp for extra heat/light. Everyone's method of seedling production is different and don't worry that what you are doing is different to what others do there are no laws to this just do what works. There are a lot of people who subscribe to the baggy method and will defend it to the core but no one covers them in plastic bags in the wild. I just use a propagator tray in my home made light box to start germination, once they have germinated and grown a little I remove the plastic cover. I find I can manage the moisture levels better that way watering more if needed or leaving them dry if not. Wait until they are bigger before re-potting. The quick growing echinopsis like these can take more organic and damp soils in the short term but once they are say the size of your finger re-pot to a much more freely draining soil mix with crushed rocks, grit, stones making up say 80% of the mix. The grit and stones make the roots stronger which is what you will really be aiming for.

Thanx
When do you give them nutrients? I have this http://www.amazon.co.uk/Chempak-Cactus- ... B004KQ4AF6" onclick="window.open(this.href);return false;
The soil they are in are sterilized soil made for cactus and i have some sand and perlite in it.

[adetheproducer]

Most will make they're own nutrients as far as organic requirements are concerned, the mineral nutrients are the ones cacti really need and they will extract those directly from the minerals in the soil mix. Have a look at the xerophylia.ro website, in particular the issue called the stone eaters. Most of my cacti do not have any actual dirt except for a few echinocereus and gymnocalyciums, maybe a few more but the vast majority are grown in pure crushed stones, chippings and grit mixtures some with clay included so mainly mineral rather than organic materials. A lot of cacti are like mosses and can happily grown without organic soil straight on rocks even. They are not like other plants and have adapted to live in poor soils with little nutrients, there are even arguments they are able to fix nitrogen potentially with symbiotic fungi/bacteria which it is know they already do to dissolve minerals directly from dry stone. I have some year old epithilantha seedlings which have never seen dirt or fertilizers just grown in pure crushed limestone, sandstone and granite mixture and given only rain water which are thriving and growing steadily.

[daffe]

Most will make they're own nutrients as far as organic requirements are concerned, the mineral nutrients are the ones cacti really need and they will extract those directly from the minerals in the soil mix. Have a look at the xerophylia.ro website, in particular the issue called the stone eaters. Most of my cacti do not have any actual dirt except for a few echinocereus and gymnocalyciums, maybe a few more but the vast majority are grown in pure crushed stones, chippings and grit mixtures some with clay included so mainly mineral rather than organic materials. A lot of cacti are like mosses and can happily grown without organic soil straight on rocks even. They are not like other plants and have adapted to live in poor soils with little nutrients, there are even arguments they are able to fix nitrogen potentially with symbiotic fungi/bacteria which it is know they already do to dissolve minerals directly from dry stone. I have some year old epithilantha seedlings which have never seen dirt or fertilizers just grown in pure crushed limestone, sandstone and granite mixture and given only rain water which are thriving and growing steadily.

Thanx, interesting reading
Its http://xerophilia.ro" onclick="window.open(this.href);return false;