Sickly Lithops

[Cactusgirl]

Two of my Lithops are drying up and disintegrating! Not sure why this is. The greenhouse does have shading and lots of ventilation including solar fans. I'm watering them about once every 8 - 10 days presently due to the intense heat. Anyone know what I'm doing wrong?

[Mike P]

Any chance of a photo?

[Cactusgirl]

[Cactusgirl]

No idea why the photo is upside down!

[Aiko]

Anyone know what I'm doing wrong?

I fear you have just answered your own question...

I'm watering them about once every 8 - 10 days presently due to the intense heat.

Lithops can last a long time without water. Golden rule with succulents and a diamond rule for ultrasucculents like Lithops: if you are unsure to water, then don't water! Don't fix yourself on a strict regime, a watering regime this strict almost every week or every other one and a half week seems way too frequently. Especially with this heat, which seems contradicting, but they shut themselves down when the nights are so very warm. Better to keep them dry, Lithops like cool weather much better. They can withstand droughts for many months or even years, also in this heat. The roots however remain a fragile part of the plants, and can cause rot easily when the roots are disturbed or are way too wet for too long.

At least the heat and water seems to have killed the L. karasmontana. The other Lithops seems to be fine enough for now although hard to judge the state of the one leaf that is diminishing, based on this photo.

[Cactusgirl]

Yes seems odd given the extreme temperatures but I guess they stop growing in the high 40's so then water becomes unnecessary and a danger? I will infuture become very conservative with the waterings. Should I be treating my 8 month old Lithops seedlings same as the adults and restricting their water too?

[iann]

The L. olivacea head looks like it may have been scorched. The other is too far gone to diagnose. Might be overwatering, or could also have been scorched. I damaged several Lithops this year, and not on a particularly hot sunny day, just not enough ventilation inside the greenhouse on a mostly cloudy day. I also wouldn't be watering adult Lithops every 8-10 days, just maybe half that often. Make very sure they are completely dry from the time before, avoid watering until the plant shows at least some hint of being thirsty, and avoid watering as much as possible in very hot conditions. You may never kill a Lithops in your entire life by underwatering, it would take a superhuman amount of neglect.

[Aiko]

Small seedlings are less strict regarding water. I always give my one year old seedlings a good soaking once every week assuming the soil has dried out in between, no matter if it is warm or cold.

Older seedlings (depending a bit on their size) will have to get used to less frequent watering.

[iann]

Yes seems odd given the extreme temperatures but I guess they stop growing in the high 40's so then water becomes unnecessary and a danger? I will infuture become very conservative with the waterings. Should I be treating my 8 month old Lithops seedlings same as the adults and restricting their water too?

I would water this year's seedlings more often than adults, but still not every 8-10 days. They will last far longer than you expect without water, especially if they still have some seed leaf left. They are even more sensitive to over-heating in the sun though, so a touch of shade is a good idea.

[Cactusgirl]

Thank you for the advice and from now on the Lithops will be on a diet when it comes to watering! I will water the seedlings though as soon as totally dry which is more or less what I'm doing now. My partner has suggested leaving the shading up all year as the greenhouse is South facing (think it's easier for him not having to take it all down!) At first I said no it had to come down. Now thinking maybe leave it up.