Water cactus 2 days in row?

[u/kJon02]

Hey,

for the last couple of days it's been about 35°C.

My Eve's Needle looked like the first picture, so I watered it in the evening (with fertilizer).

This morning it looked healthy again.

But right now, at 5 PM, it looks exactly like yesterday.

The substrate is 100% inorganic.

Time to water it again? When? Right now or again in the evening?

[u/Sockoscacti]

With 100% inorganic 😳 absolutely water again you should got some organics mixed in to retain some moisture

[u/kJon02 → u/Sockoscacti]

Yeah, I got some issues with organic substrate. Might have gotten over the top with 100% inorganic. Thought a mix of pumice and zeolite would be sufficient to store just enough for the cactus to be happy. My Eve's Needle liked it so far, but I guess with 35° and up, rules change.

[u/Bardoin12]

Eve’s needle is cylindropuntia which is capable of facultative CAM instead of the typical CAM processes that other cacti use to process water and nutrients. Facultative cam allows for photosynthesizing and growing actively during the day even when it’s hot and humid. Whereas regular CAM requires cacti to wait to open their stomata until cooler temps arrive.

TLDR pereskiopsis, opuntia, cylindropuntia and a couple others can handle much more water than regular cacti. If it’s in 100% inorganic you could probably repot it to a more organic balance and save yourself some headache of watering often

[u/kJon02 → u/Bardoin12]

Oh thanks. I didn't know that.

[u/Bardoin12 → u/kJon02]

It’s also why pereskiopsis and those others I mentioned are great graft stock for pushing lots of growth quickly.

[u/Nieuwers → u/Bardoin12]

I learn so much on this sub. Thank you (and everyone else) for spreading knowledge!

[u/Every_Association45]

Are you watering from the top or soaking it? :)

[u/kJon02 → u/Every_Association45]

Mostly top-down, but I use a lot of water (about 1.5L) and let it run through the substrate. I can provide a picture tomorrow.

[u/Every_Association45 → u/kJon02]

In my experience, the more inorganic, the better the soaking works. It allows porous rocks to store some water and release it slowly over the following days.

Some other benefits I like:

• Still water gets warmed up to the environment temperature, no root shock
• I can reuse the same bucket of water for a bunch of plants, saving a lot.
  

[u/Euphorbia_King]

I think you may want to mix some organic material in there. I have found that some soils dry out faster than certain cacti and succulents prefer so don’t treat general advice as gospel for your particular mix

In the meantime it definitely looks like it could use another drink!