What type soil is it in? Do you keep the soil damp- these like to dry somewhat before watering. When you repotted it, did you remove the old soil?

Sans2014, thank you for your comment. I water it plentifully when at least top inch of the soil dries. I noticed that If I let it dry too much the newer leaves get soft and droopy, so I learned to water before that happens.
It will be with me 3rd season now, though it didn't grow that much last summer. It was repotted twice and I did remove some of the old soil both times, but not all of it. It is in store bought all-purpose soil (that was supposed to be rather good quality) with expanded clay balls on the bottom.

As I am thinking now, I might have been guilty of overwatering lately.
My plan now is to repot into fresh, more loose soil for increased aeration / less water retention.
Should I cut off the leaves that show all these black stains?

Don't know what you mean by loose soil, I'd suggest adding 50% perlite or more to fresh mix & repotting.

I don't know Springtails or the black spots, will leave that for others.

Expanded clay balls at the bottom, hum..... Generally speaking gravel and the like once were recommended for "drainage", this has now been shown to be counter productive as it allows a soggy bottom (like a wet sponge will drain off super saturated water, but the sponge will remain wet), this soggy area is an anaerobic zone that can kill roots. You might try watering the plant when needed and allowing all excess water to drain away not even collect briefly in a saucer but drain freely away. That might help till you get around to repotting in the future. Dispense with the drainage layer then. 50% perlite is a good suggestion. Repoting would likely rid any bug issues that remain.

lmontestella, Sans2014 thank your very much for the suggestions.

I have never heard that the "drainage" layer can cause harm. I thought I am doing the right thing putting some epanded clay in the bottom. Thanks.

So no clay layer just new soil 50% perlite. Would it be a good idea to also add some pine bark to the mixture?

Still my biggest concern is strange spots and irregular yellowing. I just hope it is not fungus that could spread to all of my other plants.

Excuse me for double posting. Here are some more detailed pics:

The close up of the leaf I cut off. It didnt show any black though.

Other leaves. Uneven, bumpy texture and small holes:.

This is the root ball. It is not wet nor soggy. Need to pot up.

What can be seen of the root ball looks healthy- so that is good. Clay pots breath better than Plastic- once you use a 50/50 mix You might need to adjust your watering regimen- to keep from getting too dry as your mix will drain and dry faster. If you find it dries too fast you might need to switch to a plastic pot, but for now I think your terracotta pot will be fine. Pine Bark if you have some add it.

I am not sure what to make of the bumps. Hopefully Karen will know more on that.

Ok, thank you for the tips. Thats what I am going to do. I love all my terracotta pots and honestly dislike plastic pots or any palstic really ...so I hope to keep it.

I would be also very happy to hopefully get any clues on the other issues. For now all of my research leads me nowhere. As for the black spots I started wondering ...might they be just a natural coloring?

The terra cotta balls are both porous & absorbent (as fired clay). It's bad as they're keeping the lower soil too wet & not allowing the plant to breathe properly (roots can't take up oxygen in wet soil).

I think you need to change to all new soil w/ 50% perlite as suggested. I'd skip the bark, since you're already struggling w/out it. Often times simple is best.

This plant PREFERS the plastic, it holds the humidity better. I've grown it in both. Also this benefits greatly from a humidity tray (easy to look up).

Sorry, I know nothing abt the black spots.

You may think it's getting a lot of light, but sorry to say, it isn't enough. That's what governs the bright colors. Give it much more, brighter light (direct if possible, exposed gradually to start) & its bright colors will return, otherwise, it'll be healthy but green.

I found these plants drink copious amounts of water & I used a pebble tray, gave it longs drinks, pretty frequently & mine did fine. I had to give mine away when it grew too big for my space.

I'd try to get ALL of that old mix off, even if you have to rinse off the roots, it matters (esp. w/ the peaty mix & bugs).

Lena / Karen

Thank you all for every precious advice.
And also excuse me if my English is a bit odd sometimes since obviously it is not my first language. I find this forum amazing, so decided to join in.

I am leaving the leaves /spots issue for now (to hopefully figure it out soon).

I will take some steps following your tips and update you in the near future.

Your English is fine Dominica, pls don't worry about that.

You could even trim some of the roots off the plant, would make it easier to repot. You could just slice off the bottom 2 inches (5 cm), wouldn't harm the plant, I promise.

These are tough, strong plants, it can have its roots trimmed just fine.

Thanks for the tip Karen.

I have not repotted the Croton plant yet, but I did prepare a mix.
I am so worried it turned out bad. This is what I did:

I used store bought soil with Osmocote fertilizer - it said "super light" on the package. They do not give actual information on the ingredients here though. It only said it is a 'peat soil' and is reach with humus. I am defnitely no expert on soil, all I can say it indeed was light and soft to touch and had some perlite already, not much though. This is how it looks like, different to what my plants were in before for sure.

To that I added about 40% of perlite.

I planted some other, healthy plants first, then watered plentfuly. And as I have zero experience with different soils, this is where I became worried.

As I poured in water, the mixture soaked up alot of it, I'd say twice as much as usually until it started to drain. When soaked, the water was draining very, very slowly through the soil and instead of freely going through as it was with prevous soil, it formed a pool on top of the mixture surface for a good 30 seconds.

Don't know if that helps, but This is how it looks like, still very wet since yesterday.

Is this how it is supposed to be or did I totally screw this up? Please, help!

No, I don't think it's totally screwed up, pls try not to worry so.

From the look of the perlite, I think OK, but that soil is very fine particles. Unsure about your description of it taking time to drain, but it DOES drain after a while right? Still I'd add more perlite.

Ideally I'd try to avoid soils w/ fertilizers as I would wish to control that myself, but it's not always possible.

Do you know what the earlier soil was?

The bumps and black spots are oedema, a physiological disorder usually caused primarily by over-watering and exacerbated by a number or other cultural influences. I wrote this about oedema as a contribution to another thread similar to yours:

Oedema

Oedema
is a physiological disorder that can affect all plants. It occurs
when the plant takes up more water than it can rid itself of via the
process of transpiration. The word itself means 'swelling', which is
usually the first symptom, and comes in the form of pale blisters or
water-filled bumps on foliage. Under a variety of
circumstances/cultural conditions, a plant's internal water pressure
(turgidity) can become so high that some leaf cells rupture and leak
their contents into inter-cellular spaces in leaf tissue, creating
wet or weepy areas. Symptoms vary by plant, but as the malady
progresses, areas of the leaf turn yellow, brown, brown with reddish
overtones or even black, with older damage appearing as corky/ scaly/
ridged patches, or wart/gall-like bumpy growth. Symptoms are seen
more frequently in plants that are fleshy, are usually more
pronounced on the underside of leaves, and older/lower leaves are
more likely to be affected than younger/upper leaves.

Oedema
is most common in houseplants during the winter/early spring months,
is driven primarily by excessive water retention in the soil, and can
be intensified via several additional cultural influences. Cool
temperatures, high humidity levels, low light conditions, or partial
defoliation can individually or collectively act to intensify the
problem, as can anything else that slows transpiration. Nutritional
deficiencies of Ca and Mg are also known contributors to the malady.

Some
things that can help you prevent oedema:

*
Increase light levels and temperature

*
Monitor water needs carefully – avoid over-watering. I'd heartily
recommend a soil with drainage so sharp (fast) that when you to water
to beyond the saturation point you needn't worry about prolonged
periods of soil saturation wrecking root health/function. Your soil
choice should be a key that unlocks the solutions to many potential
problems.

*
Avoid misting or getting water on foliage. It slows transpiration and
increases turgidity.

*
Water as soon as you get up in the AM. When stomata close in
preparation for the dark cycle, turgidity builds. If you water early
in the day, it gives the plant an opportunity to remove (for its own
needs) some of the excess water in the soil.

*
Put a fan in the room or otherwise increase air flow/circulation.
Avoid over-crowding your plants.

I think you'll find this overview that provides insight into things you can do to keep your plants healthy and attractive to be useful. In most cases, plants that lack the glow provided by good health are suffering from poor root health. Keeping roots healthy is essential, not optional, if a healthy and attractive plant is your goal. Also, even though your soil is currently very water-retentive, you can fix by using a little very simple science - and it takes less than a minute. Let me know if you have interest .......

Al

Karen, I made some experiments wth different mixes of the soil and ingredients I already have. Eventually I worked with what I have made previously, added more perlite and some standard soil that I used to use before (which is more sandy, does not have all the fine fibers and is not so 'spongy'). This mix drains well but only when I put some pebbles or clay pieces in the bottom of the pot. Otherwise the hole gets plugged easily. Other than that I think it wll be fine.

I take it as a time to learn - I'll try not to worry too much, but also I'll take every advice, especially from kind and experienced growers that post here. :)

And, who knows, maybe someone else will learn from that too.
____

Al, thank you alot for this comprehensive answer. I would never have guessed the reason myself. I am very grateful for the explanation!

Great to know that it can all be fixed. I am sure that sooner or later (and probably with some mistakes that cannot be avoided), but I will get there to having a healthy Croton :). That's because now I know better where I am going. Apparently it is about time for me to start beeing more observant to the plants needs and use all this new knowledge. Firstly I stop misting right away.

Please, I am very much interested in this mysterious soil science.
...
Even more now, that I read what you say: "Soils made of any combination of peat, coir, compost, sand, topsoil, and other fine particulates are going to be very water retentive, (...) and they cannot be suitably amended to correct drainage or the height of the perched water by adding perlite or other drainage material." From that point of view, what I just did with my soil doesn't make much sense.

Al thank you again. I just want to say that I highly appreciate the time and effort that you put into passing on your knowledge.

I did some reading that you suggested. I also studied your 5-1-1 and gritty mix. However, not only was I afraid to make such a big shift, but also I struggled finding all the ingridients. Especially peat moss (it is under protection here).

Stll, 1: I am afrad that the mix would dry out too fast when I am away for 5 days or so, from time to time. 2: I don't have a garden or big space to do even messier mixing.

However, I want good health for my plants and want to learn how to provide that ...Unfortunately, within the listed limits.

To conclude I need to make "something" that satisfies my plants and works for me as well. I think that would be a mix that drains fast, but still keeps some moisture, ideally mixed from as much ingredients I already have + those I can actually get...

The things I have:
perlite,
expanded clay pebbles,
all purpose standard soil,
"light" soil (it just says: 50% lighter whatever it means, very fine particles, rather spongy).

I can get:
pine bark,
(maybe compressed coco coir if I try hard and if it is even useful).

Consequently would this work - pine bark 40% + perlite 35% + 25% soil?
Or would you suggest something else?

I do have more plants that I suspect start showng very early stages of struggling due to inadequate watering / water retentive soil or some that look super healthy but I know they are supposed to be in a fast draining mix. I have Calathea, Stromanthe, 3 Ficuses, Monstera, 2 Asparagus, Musa Dwarf, Peace Lily and Croton. If possible, I would like to create a mix that all of my plants will appreciate.

Lastly, would repotting again in June some of the plants that I have just repotted be a good idea?

Thank you for all your time and patiance,
Dominica

Consequently would this work - pine bark 40% + perlite 35% + 25% soil?
Or would you suggest something else?

Don't take what I say as trying to take control of your growing experience by forcing my ideas on you. I always want you to make decisions that increase the likelihood you'll have a better growing experience, but I see my job as ending after sharing the information you need to make good decisions. If there are alternate opinions that disagree with what I offer, I'm very happy to offer the science that lead me to my conclusions and let others decide the direction they'd like to take.

Getting to your question, let me say that you can start with a short list of ingredients from which a very good soil can be made, and combine them in such a way that the soil is, from the plant's perspective and practically speaking, unusable. I described the 'threshold' at which you start to get a significant gain in drainage and particularly in aeration. In review, the threshold is the point where there is exactly enough fine material to fill all the spaces between the larger particles or coarse material. If you're using a mix of pine bark from dust to 10mm with the average amount of fine material in the bag, the threshold should be somewhere around 3.5-4 parts of bark to 1 part each of the peat and perlite. By increasing the % bark from that point forward is where the medium shows the most gain in aeration and drainage. Decreasing the amount of bark from that point decreases air porosity and increases the amount of perched water a soil holds at container capacity, which is a measure of how much water is in the soil when it has been fully saturated and allowed to drain. The amount of water in the soil at the time it stops draining is called container capacity. You can also do things to increase water retention w/o significantly decreasing aeration and increasing the ht of the PWT. For instance, if you are using a well-aerated medium that you feel needs more water retention, adding a material made of larger and internally porous particles to the mix (like appropriate sized Turface, calcined DE, pumice) increases water retention w/o decreasing air porosity.

Imagine any soil at all that has perlite in it. Perlite is not internally porous, so substituting the volume of perlite with a product that DOES hold water internally can significantly increase water retention. If the particles are larger than the perlite, it actually increases water retention and aeration simultaneously.

Where do you live? The closer you are to the equator, the less impact the timing of repotting has on how your plants will respond.

Al

Don't take what I say as trying to take control of your growing experience by forcing my ideas on you.

Of course I don't, that would be ridiculous. All you say sounds very logical and I trust your experience - that is why I keep asking. It's just alot to process for a beginner like myself, but you have to start somewhere.

I started growing plants just two years ago, and fell for 'house plant gardening' immediately. People compliment on my beautiful plants, so I must be doing something right, but noone thought me how to care for my green friends. I learn everything from the internet, from kind people like you who wish to share what they have learnt and from second hand books. As I have very little experience myself yet I rely on experience of others in many cases... at least to start with until I find my own ways. And soil - black magic to me. As I understand the importance of it, I am impatient to learn all about it. But! thanks to you, I have already started to make some notes.

Not close at all - I live in central Europe (Poland).

Your attitude + your enthusiasm should help you advance quickly. I see over and over that those who take the time to understand what they're seeing in their plants and how what they do affects them, leave others standing in their slipstream as they whoosh past. So, don't stop asking questions and learning new things.

Your only job is to identify what's limiting your plants and the the greatest degree you're capable of, eliminate the limitations. That's pretty much the sum and substance of taking care of plants after all is distilled.

Al