My guess for the cacti is root rot from soggy, poorly draining soil combined with lack of adequate light/heat.

the succulent likes more water than the cacti do, but I have a feeling if you keep up with your watering regime, it eventually will succumb to rot as well.

I would pull all of them and check their roots, let them dry out a bit while doing what needs to be done to remedy the soggy soil problem. As well as not watering as often.

Always check moisture of the soil before watering, with a finger, a wood skewer, something.

The good news is, you can cut off the rotten part and leave it on a bright counter top (not direct sun) for about a week or two. If it still seems a little moist near the cut side, you can wait longer.

I've been trying cinnamon as recommended by many people here. If anything, it helps stop the bleeding. Lol.

Sorry, I forgot plant number one.

it looks pretty good, but it also seems like it's going to start having problems soon (if not already in the roots) if something isn't done about it.

I would say plant #4 has probably been doing a good job keeping your cacti alive by sucking up some of the excess water in your soil.

You can keep succulents with different watering needs together, just need to have a good freely draining mix (aka not potting soil or miracle gro alone).

Of course, as Rina suggested, the closer the plants are in care, the less stressful it is for the grower's worries. =)

There are planting techniques like sloping the soil or having the more water sensitive plants higher than the rest. It is easier for the more experienced (I have not been so daring in my pots and prefer to keep them mostly separate).

Ok so an update of sorts. Being incredibly paranoid, I made the grand trek to our nearest Target and procured a few things - gloves, small shovels, sand, a plastic pumpkin [to be converted to a pot], and a small plastic trash can [also to be converted to a pot]. Additionally, I deemed it worth the struggle to pull all the plants out of their soil, and boy oh boy were the results interesting. (I've posted photos below) Plant 1's roots were completely rotted away, but the rot hadn't quite reached the plant itself, so I pulled some of it to dry and propagate. Plants 2-4 are all root bound. I can't tell if they're so root bound that it's going to be the cause of their demise? I need help on this front. However, their roots overall still seem healthy. Also, in the process of taking them out, I removed their supports. They had just been transplanted (as Rina mentioned) which is why they had supports, their roots had not taken hold. Now, obviously, I know that the fact they were root bound caused that.

So a few questions:

How should I mix the sand and soil to improve the drainage? It was really really really wet, so I'm letting it dry out now. My room is VERY humid. I can't even hang dry clothes, they stay damp for days.

Given the above, how should I adjust my watering? I noticed that the top soil will be very dry while the bottom soil is absolutely soaked. Should I plant in shallower pots to avoid this?

What's the best way to propagate my Haworthia?

Thanks so much guys!

Plant 3

Plant 2

Plant 4

Plant 1

You've made some good and helpful discoveries there. I like repotting plants as soon as I get them because it's easier to assess their state and health. If I don't repot... it makes me SO curious what it looks like beneath the soil!

Some answers to your questions:

1. Sand (unless it is very large grains) will decrease drainage.
2. Humid room = you need an extremely well draining mix with low water retention.
3. Adjusting your watering will not be able to fix an unevenly drying soil mix.
4. Shallower pots will help, but not really 'solve' the problem (aka your soil). You can buy half-height pots for wide, but shallow plants. Orchid pots with slits on the side add extra air for the roots. Unglazed terra cotta is best in your situation.
5. Best way to propagate Haworthia is to wait until it grows pups, then when they are big enough, gently separate them from the mother plant.

To help resolve your soil woes:

1. You can mix up your own batch of gritty mix, with a larger percentage of grit to reduce water retention for your humid, indoor growing area.
2. You can try adding a lot of sifted perlite (to remove small bits/dust) to your new soil. At least 75-80% perlite would be beneficial.

Don't forget to remove all the old soil before you put them in your new mix too. =)

Also, going the perlite route, you'll need a top dressing to keep the perlite in solution. Otherwie it'll just float to the top when you water. It's a pain, lol.

Oh! Another good thing about top dressing in this way is it helps keep the plants steady and away from the moist substrate so even if you do have a little more water retentive soil. I often do because I keep plants outside in 110+ heat. What? They love it. At least that's what my desert rose is telling me. She's starting to make a flower (I just got it in June). My aloe has literally gotten 4 times (that may be a modest guesstimate) bigger since I got it this spring from some nursery, bare root out of California. It was still in its spotted, juvenile leaves. I can't remember if it had started growing into a rosette yet or not. I had to cut a few leaves due to some soggy soil and the monsoon season we had this year. I keep it in a 2 gallon smart pot so I guess the roots are kept pretty cool, comparatively.

Anyway, looking at yours, they really don't look bad at all for the conditions they've been kept in (through no fault of your own, can't be expected to know everything). I actually think you've done a really good job with them.

nothing seems rotten or anything. I think you are intervening at just the right time!

Another update and more questions! Thank you laticauda, it's hard in a 3rd floor dorm room with no way to grow outside...And ewwmayo do you think I could get those materials on Amazon? I don't exactly have immediate access to ant gardening stores or stores that have gardening resources. This is what I've got now:

Dry soil

Some sort of sandy stuff

I know this is a ridiculously large bag... but I think someone else on the forums orders these. You can get smaller bags online, hydroponics stores, and garden centers. The bigger the pieces the better:

Hydrofarm 50L Super Coarse Perlite

You can just buy a normal small bag and sift it with a kitchen sieve, just don't breathe in the dust.

Another forum member, Bouldergrower, uses sand to great success for his plants. They grow in a very bright window indoors and I think he takes them outdoors too. This is what his sandy mix looks like: Good sand for succulents!

In another thread, he commented "My nursery pot is coarse sand from a nearby stream bank sifted in a spaghetti strainer to remove most all of the fine stuff. I set in a sink of water once a week and let it sit in full sun in a south window."

To me, his looks a little bit chunkier than the container of sandy stuff you have? Yours reminds me of aquarium gravel actually, I use similar stuff for a top decorative layer for some of my succulents:

You can also get some pre-made mix online. I've never tried it myself (others have) and it is a bit pricey, but not that bad if your pots are small: Gritty Mix online

Edit: So the answer is yes, you can get the components yourself online. I believe they sell granite grit on Amazon, as well as Turface. I'm in Canada and our Amazon is terrible. =P

Thank you everyone! I really appreciate the help!