Answer: The Apentia belongs to a family of plants called Aizoaceae which is classified as a 'dicot'. This plant can actually be hurt by products like Ortho Weed-Be-Gon (which target dicots as opposed to grasses which are monocots). Don't use broadleaf weed control products as Apentia is also a broadleaf plant.
Unfortunately, there are no home owner approved herbicides which selectively targets monocots (grasses) and leave dicots (broadleaf plants).
I recommend mulching in between the iceplants with a 1-2" layer of shredded hardwood mulch. This should keep the weeds to a minimum. Wish I had better news for you!
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