BCSS - Forum

Hi all,
This Cereus peruvianus had some slug damage in the autumn. There are now black and rust color marks. I'm guessing fungus? Most stems have some. Is it recoverable do you think?

The second picture is an Opuntia from the cold greenhouse. Two pads had some rot which I cut off. This pad only has a little. Should I cut it off? Its now in the house.

Finally a picture of moth damage for interest. The caterpillars like aeonium shoots as well as pelargoniums.

Any tips welcome. I'm avoiding using pesticide unless on indoor plants.
Andy

I have had moth damage on my Aeoniums, too. A small green caterpillar 'sews' the leaves together to make a nest, which runis the leaves. The best control for this is to check frequently and remove the caterpillar. I have been having this problem for a couple of years now and fortunately Aeoniums grow fast in summer and the damage grows out. I have come across the same on Pelargoniums, I cut off all the leaves back in late Autumn and hope the problem does not re-occur. There has been a lot of this across the country, I don't use any controls just regular checks.
I can't help you with your Cereus or Opuntia, as I have been fortunate with those.

The black markings on the cereus look like cold damage. This plant doesn't like the cold in my experience and I would recommend you maintain it in a temperature of around 10 deg C. With the opuntia I think I would detach the smallish offshoot at the top (partly out of the picture) and root it once it has calloused over. The rest of the plant might not be salvageable.

Thankyou Liz and Rod.
As you say the caterpillar pulls the leaves together damaging the growing point for a while. They also damage Easter/Christmas cacti. The first sign of trouble is tiny seed like frass around the pots. If I spot this I look for the the caterpillars. Often I don't notice until they've caused damage.
The greenhouse has dropped to 5 degrees quite a few times. Most plants are fine, but as you suggest the cereus wants it warmer. Next winter I might use a bit more insulation. Pilocereus also suffered from small slugs and similar markings. Andy

I had the same moth it turned out to be tortrex.

The various tortrix moth caterpillars have this behaviour of sticking leaves together, using the plant they're eating as a protective cover. I've had Aeoniums and Echeverias in the greenhouse damaged this way; roses and all sorts attacked in the garden.