Hi all

I have 4 cacti that I received in august this year and the tops have started to go black, I will attach some photos, should I cut the tops off?

Also how do I stop this happening again

Thank you guys so much for your help
Jordon

Are they squishy?

You might be giving them too much water. If that's the same black mould as was on one of my cacti, it needs to be moved to a warmer/sunny location

Thanks for your reply guys,

They are not squishy.

In regards to water, I water them every 1 - 2 weeks depending on the weather, if it's 30 degrees Celsius for the whole week with no cloud then I water them once a week. Otherwise they get one watering a fortnight.

The soil is a 50/50 perlite potting soil mix.

They are in a full sun position with no shade until 5-6 PM in the after noon seeing sun at approx 8 AM each morning, there is nowhere I can put them where I live that sees more sun than that. The temperatures have been very steady at 22 - 35 degrees Celsius, never going below 18 degrees Celsius.

Thank you again for your help guys.
(:

In that case...I probably wouldn't worry about it unless you notice the stuff is spreading. If that were to happen, get some natural fungicide that wont leach into your yummy cacti.

Thanks OneEyeAscension,

Is it normal for there to have been no new growth in around 3 months (that's when the top was cut off.)

Thanks

Unfortunately I don't know. I've grown all my cacti from seed, they're still not big enough to harvest. But 3 months seems like a long time...It 'may' be that you have fungus growing on scarred plant tissue that are inhibiting the plant's ability to sprout babies (I'm really just an amateur with limited experience).

There are a few cacti experts on this forum that will help you out if you ask.
Good Luck!

I have just received my very first pedro cuttings only days ago, so I'm certainly no cactus expert. However, from the info I have gathered, the common practice is to cut off the moldy top, and then allowing this exposed "wound" to dry for a few days up to two weeks at room temperature. You can speed this up by putting it in front of a fan for 24 hours, then letting it dry naturally for the remainder of time. Once properly dried, a callous or "scab" will form on the wound which will protect the exposed tissue from mold.

I'm not entirely sure if this can be done in the same way with a potted plant though.

Looks fine to me. If it is not squishy it is not an issue.

I have had cuttings fail to pup or branch for well over a year before.

Be patient.

A little mold on a cut surface is fine so long as it's not weepy/oozy or squishy internal rot (typically the whole cacti is dead once rot hits the top, tending to come from the roots of overwatered cacti). You may want to go ahead and cut that tip off at a slant in you live in a location with a lot of rain however, regular standing water in that little bowl of an indentation could cause problems in the long run.