Plant choice is critical
If inappropriate plant species are selected for a green structure then the results will inevitably disappoint. The local climate and the amount of shade are central considerations for those who put up planted walls. Everyone wants a wall that flourishes in an attractive way and which is hardy enough to withstand the worst of the weather. The variation in local weather should not be underestimated.
Some plant species are simply too expensive to be a shrewd choice. Customers do not want to pay over the odds for a wall, especially in periods of economic uncertainty. Luckily many plants can be found at quite reasonable prices.
If people pick plant species which are not up to the job then an awful lot of extra maintenance will be needed. This is not just bad in terms of cost. It is also a problem in terms of practical disruption. If the planted wall is a large one, the costs of poor plant selection will mount quickly.