One of my trichocereus pachanoi cacti had a root fungus that turned the top of the cactus to a black mush, after re-potting and soil replacement the cactus healed, this was quite a while ago, the cactus has been very healthy for last last 1.5 years. The spot where the "mush" was healed, and ever since long arms have been sprouting from the top. Ok, heres the question:

The arm on top of the cactus is becoming to large for the base to support, I want to remove the arm and allow it to root in its own pot, though I have never done this before and don't quite know how to go about it, I was told that I could just remove the arm and place it in soil and it should root, is this really the case? There's nothing else I have to do but remove the arm and place it in its own pot of soil?

I really do not want the arm to die, so if I'm going to remove it I want to be 100% sure that I'm doing it properly, so any advice or guidance would be very much appreciated.

(I've attached I picture of the cacti I'm speaking of)

Thanks,

-EG

I apologize for not catching the typo in the post heading before I posted.

-EG

You want to make sure to cut it with a freshly cleaned knife at a slight angle.

The cutting then needs to be kept in a dark cool spot with a fan blowing on the cut end for about 24 hours I believe. Then you can take the fan away but leave the cutting in that spot until the cut heals and callouses over. Once that happens put it into its own soil and leave it be for a month or so and it will start to root.

Don't water it until it is fully rooted as well.

What I would do is cut the pup off, dust with sulfur or rooting powder (or both) if you have some, set it in a spot that gets indirect light during the day, wait till the bottom is completely callused over (probably 2-6 weeks), then put it in a pot with soil in a spot that gets lots of indirect light (but no direct sun for more than a few minutes) and don't water it until it sprouts roots. You can (very very very) lightly mist the top of the soil maybe once every two weeks to encourage it to sprout roots.

Also, another piece of advice. If you can you should put those plants in some good full or at least partial sun. The pup looks pretty etiolated, so more light would help it fill out. Also, They tend to rot easier in low light. Especially if you're watering them like you would a plant out in full sun. I always differentiate my watering frequency depending on how much light/heat they're getting and how fast they're growing. The more light/heat/growth the more frequent the watering/feedings. It's something that you have to experiment with for a while to find the best methods for your climate.

Good luck!
hostilis

Thank you for all the information it was most helpful and much appreciated.

-EG

They are in partial Sun, and the light box stays on half or less unless it's cloudy.

-EG

That's a south facing window, so they have been doing pretty well.

I do need advice on a tried, tested, and true watering schedule and watering methods though.
Any other helpful tips would be much appreciated, thank you all very much, you have been most helpful!

-EG

You can edit and correct it : use the edit buton on one of your post and you can change the title in subject's box.

The watering schedule depends on how much light/heat/growth it's getting/putting on. Also by how fast the soil dries out completely, and usually indoors they do not dry out so fast because of lack of wind/heat. Also the pot type and soil mixture. What kind of soil and what kind of pot are they in?

Here's a pic of the pots, one is tan plastic the other is ceramic. They are both in home-depot cacti/succulents soil.

-EG

Okay. That soil looks like it has a lot of perlite and bark so it will probably dry out fast. A few things to keep in mind is that plastic and glazed ceramic pots take longer to dry out. Unglazed terracotta pots and cloth "breath" so they dry out faster. 2 weeks is a good place to start, but check to see how long it takes them to dry out and if it isn't completely dry (not just the top) in 2 weeks then increase the time between watering.

Thank you, you have been most helpful and it is most appreciated, thank you again.

-EG

For sure! IF you ever have any questions hit me up. I'm always happy to help out. Although there are some others that are more qualified than me. I mostly grow small globular cacti as opposed to trichocereus.

Good luck!
hostilis

Thanks again!

I have still not removed the "arm" yet, but I did set up a pot and soil for when it's ready to root, I'll post pictures as I go. I guess I'm still a bit timid about potentially killing the arm, so I've been putting off removing it, but I know when it has become it's own plant I will be glad that I did...

-E. Borodin

I have had these for 3 years now, and I'll admit there's still a good deal I don't know about their care, I've not had any issues with them, but I feel I could be doing much more, any helpful growing tips on lophs would be very much appreciated.

-EG

The bigger one on the right is definitly etiolated = lack of light.

The soil should not have those organics bits (mulch ?), there is more risk of mold. It should be more mineral.

It's just my 2 cents, Hostilis or others experienced fellows will give you more detailled and precise advices.

What indications of etiolation are you seeing?


-EEG

I think the issue has more to due with watering or a nutrient deficiency, because they are getting plenty of light (Sun and artificial)

Yeah that big one is beginning to look "deflated", I'm just not sure light is the issue...

-Eg

What would you recommend for watering? How often and how much?

What would you recommend for light? (I have a T-5 box and partial Sun from a south facing window on them now)


I'm also considering changing out the soil with those 4 lophs, I have them in home-depot cacti soil that I added some perlite to right now...what's the best way to remove them from the soil? As the roots are long and carrot like and I don't want to risk breaking them...

Thank you for all your help, it's very much appreciated!

-EG

I would also agree the one on the right is etiolating. The way it's growing in an almost columnar fashion is an indication of etiolation. It's getting "taller" rather than growing in a globular fashion. Also, the lighter green color and angular "ribs" are indications of etiolation.

The other plant looks to me like it's not really growing as if it's dormant. Has it grown much since you got it?

I usually don't worry much when I repot plants. You just don't want to damage the roots. You can actually trim the smaller roots with no harm as long as you don't water it for a while after repotting. Anyways, what I do is make sure not to water it for at least 2 weeks before repotting. Then I take a butter knife and "cut" around the edges of the pot to allow the soil to loosen and come out. Then i hold the top of the plant, tip the pot upside down, tap it with the knife a few times around the edges, and the soil should fall right out either in one big chunk or (if it's really gritty or mineral soil) it'll all fall out into a pile leaving the plant in your hand. Then I carefully break up the soil to clear all of it off the plant. I then wash the plant off to get all soil off the tap root very carefully. You can also optionally trim all the tiny feeder roots off of it to encourage it to grow new roots in it's new home. Then let the plant dry out for a day or so. Now you can put it in it's new home. Clay pots are great for slow growing globulars that don't like to have wet feet, but plastic works. Just water less.

For globulars I have two different directions to take. The habitat type hard grown plant, or the nursery type water bloated plant. For the habitat type plant I will mix gravel, pumice, course sand, a tiny bit of coco coir and worm castings, and a tiny bit of dolomite lime. For the nursery type plant I will mix 1/1/1 coarse sand/pumice/"Happy frog" soil by fox farm. I water them either once a month or once every other month depending on growth speed, conditions, and species. I fertilize usually only a couple times per growth season. A good place to start is once a month with watering. Indoors though you may want to do it less.

Another thought I would add to this is that window light is not very strong. Even if it seems like it. There's nothing like having them outdoors in the full sun.

Anyways, hope this helps!
hostilis