I have a few san pedro I started from seed (I think a few are pachanoi and a few are puruvianus. I noticed recently that a few of them started to get dark in color and looked as if they were shriveling up. They were watered almost every second day and were doing fantastic. I have a 8x 4ft t5 light about them. I kept the light about 8-4" above the cacti with a large fan blowing on them. They would dry out by the end of the day. Over a period of about 5 days a bunch of them started to turn very dark green and were shriveling up. I check the roots and everything seemed fine. The base of the cacti seemed fine too. Is it too much sunlight? To much heat? Over watering? I'm totally stumped. Only two of the 11 I have are growing normally. Any idea's? The picture of the two bright green ones are some healthy ones I took for a comparison.

Hello Taproot!
Man you have to give a lot more information and pictures for accurate predictions what might be the reason, but i will try to help im not licensed plant doctor so keep that in mind.

You might be overwatering, this is cactus its not a tomato plant dont water every day or every other day, let them establish themselves, let them dry give the roots some oxygen you wont kill them with few days without water. Its better to be underwatered than overwatered cuz your roots can start rotting and you cant reverse that, if they dry too much you can just pour some water in and your good man, more water doesnt mean faster growth. And they are still young they are probabbly not even using all the water you are giving them.

The light source..T5's are good for start but you wont be providing them with enough light soon, switch to i guess HPS for example, get a exhaust fan and if you have an air circulation fan DONT put
it to blow directly on them. T5's actually should be kept really close because they dont throw light very far away the further away your T5's are from your cacti the less light they will recive which may stress them and you dont want that. The T5's wont burn the cacti unless its touching it, simple test you can make is put your hand under that T5 and ask yourself is it too hot for me? if its good for you its good for the cacti.

Soil extremely important. What is it? this may be key to your problem what it contains?? Share that
"I check the roots and everything seemed fine." i dont even want to imagine how you did this, dont stress them it will cause them stunned growth. What size are the pots? dont let them get rootbound this is another cause of stress and stunned growth. Soil pH? N-P-K ratio? are you giving liquid organic/synthetic fertilizers if yes what they contain? Is the soil Peatmoss based or sand or whatever? you got perlite in it? what is the temperature in there day and night? humidity check that.

P.S. - Believe me the only person that can help you is yourself, i say that because only you know all the things you did to the cacti's there are TOO MAANY things that could be the cause. Read and educate yourself im sure you will find the reason. Give more info and more pics. Good Luck

Tip: I wont use clay pots next time, T5's deffinetly looks like its too high but it seems you got bigger cacti under there so its understandable, but what you can do is put the smaller cacti pots on books or whatever so they can be closer to the light. Share more info and pictures if you can.

How do you water?

How much do they get?

What do you feed them?

How much light do they get? Hours and intensity?


How old are they?

What temperature?

Did any variables change recently, like they are colder or warmer etc?


Edited to add: clay pots are tricky unless very large.
They tend to be a little too dry.

First off I just want to say thank you for you're quick responses The Entity and 0_o. Simply by reading through your posts I've learned a lot and realize that I really do need to do more research on growing these cacti. I actually wrote quick a large post before this one and when I hit post I'm not sure what happened but the whole thing was lost. I will dig a bit deeper into the world of Echinopsis and in a week or two with update you both with what I decided to do and with more pictures / details on my grow room's parameters and the condition of the aforementioned cacti. Once again thank you both so much for the time and effort you out into responding to my post. It means a lot to me ^_^

Hey Taproot!
Consider my advice but research it before you/if apply it.
BIG TIP: NEVER EVER USE SHIT SOIL/NUTRIENTS. What your cactus EATS will become, and then you gonna eat that or drink it or whatever. Once you mix your soil you cant dig it up and replace it, so remember this advice: PLAN BEFORE YOU PLANT. Enough is enough man dont overfeed dont overwater dont overdo, moderation is key and is often the fastest and best way to achive anything in life. Good Luck

Those cacti look dry to me. I think the daily cycles of wet and dry are not to their tastes. These cacti grow on foggy mountainsides so you might want to think about replicating those conditions a bit more closely. They will respond very nicely to a regular misting with distilled water, for example.

If they're in an active growing phase the soil can be kept moist pretty much all of the time - especially since they're only just past the seedling stage. Plastic pots would help with this, although I'd leave them be for a while if you've looked at the roots recently. What you can do instead is find some plastic pots that fit snugly over the clay ones. This will help slow down the evaporation and over-rapid drying out of the soil.

IME, treating Trichocereus cacti (particularly pach. and peru.) in a way more akin to tomato cultivation than the popularly accepted (mis)conception of cactus cultivation has yielded far better results than the converse. Ultimately, getting a feel for what the plants like over a number of years is what it takes. And these plants respond well to '50% tomato' conditions

That's what I thought. I have a friend and he waters his basically every 2 - 3 days. He soaks the soil. His is about 3 years old now and the thing just loves it. He has his in a a bulbous looking clay pot about 3 inches wide and 3 inches deep. I noticed mine for the most part were only shriveling just under the soil line.

That's what I thought. I have a friend and he waters his basically every 2 - 3 days. He soaks the soil. His is about 3 years old now and the thing just loves it. He has his in a a bulbous looking clay pot about 3 inches wide and 3 inches deep. I noticed mine for the most part were only shriveling just under the soil line. This was the best picture I could get of it.
I would also like to add that this happened to one of my cacti that I started the same time as all the others and I decided the only way I could potentially save it due to it's size was a graft. I knew nothing of grafts but had a christmas cactus at home and figured I would try it. In the name of science. I have a cereus tetragonus right beside it that I recently purchased and figured "hey, they look similar so maybe they're compatible. I sliced the soft tissue off the Echinopsis and beheaded the tetragonus as well. I firmly adhered the two together using a paper towel and a rubber band and about 2 months later this cacti (which was the smallest of the original batch) is now the largest and healthiest one.

Here they are I make a mistake and hit post before checking the box "attach files to this post"

Just a guess, but maybe the fan is drying them out. Unless they are sitting in 100 F direct sunlight all day the fan is probably unnecessary. Trichs are cacti but they tend to grow at higher altitudes where it's cooler. In my experience they like all the sunlight you can give them once they've gotten large enough to "harden up". They like all the sunlight but this Summer mine all stalled out a bit once thy found themselves sitting in 100 F temps. Every time it cooled off for a few days they immediately started to grow faster again.

That's a great observation Wolfnipplepoint. I honestly would have never though of that. The first graft I ever did I did because (as you can see in the second picture posted above) the cacti was clearly rotting at the base. I ended up digging up a few of them yesterday and grafted 3 more of them to another Tetragonus and one to a Pereskiopsis. I noticed only shriveling and no rot at the base. I did this with the idea that it is better to try to save them this way than to lose 2 years of work.

Taproot:
None of those pics look like Cereus Peruvianus. Too many spines and the aureoles aren't the right shape.

Am I allowed to post some pics?
This is my first post.

Yes please do I don't mind.

It looks like you take a big interest in your plants, good equipment too.

After double checking, none of your pics look like Echinopsis pachanoi either. Again, too many spines and the aureoles are the wrong shape and orientation.

Anyway, I have some very small saguaros and one of them likes to darken when the light and temp aren't high enuf. Now don't interpret this as an application for your plants. I just don't do anything about it, it's a seasonal thing, but it does drive me wild so I know how you feel.

As long as your plants are still firm and not softening, don't let the darkening get the better of you. It could mean that your plants are entering a dormant period.

Again, I can post some pics if it is allowed of noobs, somebody let me know, OK?

I don't think I'm allowed.
I can't seem to find a control to select a pic

Well that's upsetting! I was told they were listed as pachanoi and peruvianus seeds when I obtained them.

OK, here ya go:
C. peruvianus & E. pachanoi

Well that's upsetting! I was told they were listed as pachanoi and peruvianus seeds when I obtained them. Also the way you upload photos is as follows:
Create a post, at the bottom of the page there is a box that you must check saying "attach files to this post" check it,write your post or not, then click post, you'll be directed to a new page with an box saying attach or something. Click on it, select you photo and to the right of the file it will say upload. Click upload and repeat this until all your files are uploaded. Then under the files there will be a back button. Press it and you'll be redirected to my original post and your files will be uploaded.

I agree, I always cringe when faced with buying seeds.