1. First, coffee grounds are not "fertilizer". They are a good soil amendment for inground gardening or to add to your compost pile or worm bin but they have no place in a containerized soil mix.

2. A good quality, durable and fast draining soil mix for succulents and cacti generally contains minimal amounts of organic matter like compost. And garden soil is never advised for any sort of container growing situation regardless of plant type. It is far too dense and without adequate particle size to provide necessary aeration. You would be far better off with something like Al's gritty mix (see link).

3. Various species of cacti and succulents have various pH preferences but most would be happy with irrigation water that tests out to a pH of 6.0 to 7.0. pH is relatively easy to measure with the testing kits sold at any garden center. I just use tap water that I allow to sit overnight (releases chlorine, etc) and my tap water is close to neutral (7.0).

If you haven't tested the water and found it was very alkaline, and you haven't noticed any nutritional problems with plants then don't worry about ph.

Even if it is a problem don't put coffee grounds in the pot. You could make a compost tea if you like but I agree with garden gal organic fines in container mix is bad, especially for cacti or succulents which need sharp drainage.

A cheap ph test kit will cost you about 15 bucks. test the water that drains from the pot (called leachate) and the tap water. A more reliable truncheon meter is about 100 bucks. Usually no one pays too much attention to it unless they are doing hydro (solution culture) or they have already noticed a problem.

G - Here are my thoughts:

1. Do not bother, will harm more than help (more likely to attract pests / fungus / bacteria).

2. Same thing, although I'm assuming you are growing your succulents in a pot. If planted in the ground, then it would help or hurt, depending on what is in your compost.

3. You can purchase a digital PH tester for relatively cheap. It is important to calibrate the low and high set points with PH buffer solutions (PH 4.01 and 7.01). Once calibrated, you can test your water.

My additional notes on PH testing:

• If you use fertilizer, you should test the water/fertilizer mix PH before adjusting your PH. This is because fertilizer can affect PH (typically lowers it).
• It is important to store your PH tester in the proper PH buffer solution. Never distilled water and not tap water.
• It is important to recalibrate your tester before use (particularly if it has been a while). The ions transfer out and shift the readings.
• PH testers do not last forever, I think 2 years with proper storage.

Vinegar does help lower PH and is cheap, but is not a good PH buffer. Something like PH Down is more appropriate and no chance of biological fouling.

For general information:

• My tap water PH is 7.6.
• My rain water after a heavy storm is PH 6.7.

Not all succulents prefer low PH, so it's good to double check which species you are growing.

G

Not sure if you mentioned where you live? What is the climate like?

Succulents like lots of natural sunlight. Maybe yours suffered some because you took them directly from indoors (probably not much light-lesser intensity of light) into direct, much stronger sunlight? Over all, they should do better outdoors than indoors, but need to be acclimatized to different light.

Sand would be OK to use if it is really gritty - finer sand will clog up any air space so roots will have hard time to breathe, and it will also impair drainage. If you can get an ordinary kitchen sieve and sift sand thru it, keep only what stays in the sieve. Whatever falls thru is too fine to use for succulents.

Containers should have drainage holes, so excessive water could drain out. If there is any water sitting in the saucer about 20-30 min after watering, saucer needs to be emptied.

It looks like snake plants are in containers without drainage holes, and in not-so-good looking soil (judging from what's visible in the photo - I know you said you just added a layer on top, but how much perlite is there otherwise?). Without proper drainage the roots will suffer.

Can you get some grit? - like sifted sand, or even aquarium type grit. Mixing it with perlite would be better for your plants. Let us know what is available to you - perhaps we can suggest much better potting mix.

Perlite holds very little nutrients (low Cation Exchange Capacity). But most succulents do not require a large amount of nutrients. Plus you can fertilize regularly (if so desired).

If there are stores selling chicken grit (here in Canada it is easy to get in farm supply stores), that would be suitable as a grit part of mix. That is what many of us use, but not one with ground shells (it should say so on the bag).

Yes, you can increase amount of perlite - there are ppl that grow plants in perlite only - as ewwmayo said, you can add some fertlizer (he has few very good posts about all the measurements he has done regarding fertilizing, light and temps...)

Rina

Hello donotcarebear. I am also from the Philippines. :) You might want to check Cactus and Succulents Philippines on FB for more tips and information on growing these plants on our climate.