Hello, I've decided to repot my 3 cactus as they have out grown the original pots. Cleaned up the roots and leaving to recover before replanting. Are these looking healthy?
Mammillara has been flowering lovely.
Joseph's coat has started with some brown patches but still firm not squishy.
Old lady's cactus has started to feel loose in the soil but the base is firm no rot. All the roots are nice a white.
Thanks for any advice.

They were nice and healthy. Why did you wash the roots? And why are you leaving them on the counter to dry? The roots systems are very small, why did you repot?

Sorry for sounding a little grumpy.

That's ok doesn't sound grumpy at. Any advice is greatly appreciated! The roots had started to grow through the drainage holes in the pot, the Joseph's coat roots were about 2 inches out of the pot and when I removed them they were wrapped around the edge. They had recently been watered so when I removed them the soil was stuck to the roots and wouldn't break free. Somewhere online suggested soaking them for an hour to remove the soil to check for any signs of rot and suggested leaving them to dry and recover before replanting to prevent rot. Have I done wrong and if so what can I do to correct things?

Well, they are out of the pot and soaked, so whether or not you did things wrong or not does not really matter any more.

However, it is the middle of winter and even if where you are the winter may be reasonably mild, soaking plants that are generally not happy campers to be really wet when it is cool/cold and there is little light, the timing of your efforts is probably a little off. You now really want to make sure they dry out quite well and then repot them and not water them for a good long while.

The fact that the roots where coming out of the bottom of the pot, definitely signaled they needed to size up a pot, but timing... aside from time of year, I'd also not repot right after watering it made you encounter the issue that had you then wash the plants. It does not necessarily hurt to remove all the soil from the plants you are repotting, but it does increase the chance for major damage to the roots which can be a source of problems when the plants are back in soil and you water to soon or the new soil is too wet. Unless you have serious cause to change all of the soil out when repotting (say because it is really poor soil for the cactus, part of the plant had developed root rot, or some similar issue) I tend to not be too worried if most of the soil stays put and I just back fill the new pot as necessary.

What is done is done, just be careful watering cacti in winter when it is cold and possibly humid.

One last comment. Your plants look healthy, yes the PP has some spots developing, but they do that especially when things are gloomy and not warm, but nothing in your plants appearance would suggest the idea that they have major root rot problems going on. So the suggestion to wash the soil of to inspect the roots for rot seems a little out of nowhere.

Anyway let those plants dry out really well and then carefully repot them and hold of watering for a good number of weeks.

Good luck!

with Thijs on everything except the roots coming out the bottom of the pot. The Mammillaria in the first photo is the only plant with a substantial root system. Roots follow water so if there's no moisture in the soil, the roots will follow the water out the drain hole. Are your pots in saucers? That encourages roots to leave the pot but isn't the only factor.

You got a point, but unless we could see what the pots looked like it is hard to gauge the root mass, also - it is not uncommon when washing the soil like that for quite a bit of the really fine root mass to just get washed away.

Thank you both for the information and advice. The plants were in individual pots and the pots placed in a larger window display planter which had gravel in the bottom. The roots had grown through the pots and into the gravel display planter. The plants are in a warm room on the window sill and it also has a dehumidifier running so the humidity is kept at a set level. How long would you suggest to let them dry before replanting? They were soaked last night and today feel almost dry. Is the idea behind not watering straight away to allow the roots to recover and grow before they get soaked again? Many thanks.

Also if I have damaged them and they're not going to survive how soon will I know? What should I look out for first? Thanks again for the help.

The idea behind not watering for a week or so after you repot is that cactus, unlike other plants, don't have little shut off valves in their roots. So if you damage roots during the repot and then immediately water, the roots absorb moisture and rot. If you don't water for a week or so, the damaged area of the roots have a chance to heal and when they absorb that first drink, there are no open wounds to rot.

You won't know for awhile how much damage the repot caused. The first signs will be soft or black spots at the base or tip of the cactus.

That's brilliant thanks, I will leave the roots to dry and get the soil nice and dry before replanting and leave for a while before watering. Fingers crossed they respond ok. Just out of interest this is the article I read regarding cleaning the roots up...

After removing the cactus from an old container, you will need to clean the rootball and remove old soil. This should be easy to do with dry soil. But if the soil has dried and you can't clean it, place the rootball in a plastic container for soaking in warm water (around 122 degrees F or 50 Celsius) for 20-40 minutes.
After the rootball has softened, wash it with water to remove any remaining soil. Dry your cacti's rootballs for 12-30 hours so that they dry completely.
A good tip would be to hang your cactus so that roots are in vertical position. This will help the cacti to acclimate to a new pot sooner and will save roots' natural healthy shapes. Washing and soaking your cacti's rootballs in warm water will stimulate plants' growth.

Where did you get this information? It sounds like a troll.

That's not something I would ever do to my cacti.

This is commonly done in my local succulent community. I think it may have something to do with the weather. In California, you have the optimal climate for succulents and cacti.

Charlinex said:This is commonly done in my local succulent community. I think it may have something to do with the weather. In California, you have the optimal climate for succulents and cacti.

Because you live in a cold climate, you strip your cactus done to their nothings, soak them in hot water and let them drip dry?

I live in a cold climate and I have never done that or even heard about doing that.

I don't think climate has anything to do with it. I can see three reasons to go to such lengths to remove soil from cactus roots. One is if you don't like the soil the plant came in, and plan on using something dramatically different. Two is if you are of the school that prefers soil replacement as a way to provide renewal (new nutrients). Three is if you're concerned about some kind of root pest and need to visually confirm its removal. Otherwise really truly it's not necessary or fruitful to do anything other than lift out the root ball intact and place it in a new, bigger pot with more soil. The potential issue is root damage. And 50°C is warmer than I would ever subject roots to for any extended period.

Baja all the reasons you give are true. This practice is also promoted by the bonsai masters in my bonsai club. That being said, on the basis of my own experiment, trimming the roots aggressively is, in fact, very beneficial to the root growth.

My observation is, if I don't trim off the roots and just put my succulent into a bigger pot, the roots very rarely venture out of the existing root ball. If I trim off the old roots, it stimulates the formation of new roots.

I think another reason maybe lies in the composition of the soil. When you wash off all soil with the old roots, the new soil provides a consistent new environment in terms of water drainage and nutrients.

The roots are not venturing out of the existing root ball because the new soil around it is significantly different (in composition or drainage) from the soil in the root ball. Or that would be my best guess.

Exactly what I meant too. Even if it's the same soil, the old part will be depleted of nutrients and filled with old roots which may interfere with the new ones.

Wow certainly a lot of different thoughts on this! Thanks you all for your thoughts and advice. I will make sure they dry throughly and have enough time to recover after replanting so hopefully they survive this.

Cactus and succulents are different from other plants because they holds lot of water in their bodies. As a result, they grow roots more easily when the old roots are removed. The big roots are used to anchor the plants while the fine roots are used to absorb the water and nutrients. When you replant, it's more likely that most of the fine roots are lost anyway.

The most important thing is not to water too early. Good luck.