Tropicals & Tender Perennials: Help! Stuff on back of Hoya leaf, good or bad?, 0 by Kaelkitty

Kaelkitty wrote:
OK,
This LOOKS to me like the kind of age related corkiness you sometime see on the old part of cacti stems. If I have read the earlier posts correctly no-one has seen this on new growth, only on mature leaves. It may be that these particular leaves are just OLD, and the plant hasn't shed them for some reason, possibly because it is growing under cultivated conditions.

For those who have affected plants, could you estimate what percentage of the leaves are marked in this way. If there are only a few, the solution might be as simple as picking them off to encourage new growth.

Here is a photo of one of my Opuntias, showing the discolouration at the base.

Ciao, KK.