The veranda with the cactus corner on the left, with the original plastic containers. 
The top and bottom doohickeys are bolted to thin metal struts, keeping everything up. The struts are not totally stable, so we added two diagonal reinforcements between the struts. 
Each level is held to the next with these doohickeys: the horizontal part is screwed to the plank and the vertical part to the doohickey of the next level. 
The litter box is now a bit more shaded and there is still enough room to easily remove it for cleaning. 
This is the second set of containers: a bit more narrow for easier removal, one or two with more depth to leave room for the roots. 
after a year of experimenting with different types of plants, I found some that were pretty happy in this spot. Succulents don’t do so well here, it gets waaaaay to warm in summer.
Requirements
must fit exactly in the nook between the veranda windows and the veranda storage closet
must have several levels facing the window, so each pot gets maximum light
must be easy to water the cacti
must allow space for the cat litter box underneath
Design
Honestly this was not a case of thinking I can do this better, I looked in several gardening stores and just didn’t find a design that fit the nook exactly. I did see some stand alone shelf things, but they were either too low, too wide or too small, so I decided to make it myself. First step was to make a design on paper with the exact measurements required. I wanted to start small – I mean with small cacti – so I decided to make three narrow shelves on three levels.
I enlisted the help of my father-in-law who’s handy with tools and we went to the hardware store to investigate the options. I bought one plank of some wood suitable for outside terraces (I asked the store to cut it at the exact length I needed) and several steel doohickeys. Back home we browsed my extensive screw/bolt/nut collection (my dad never throws anything away, but ran out of room to store it) and started screwing everything together. Easy!
The end result looks nice: the wooden planks give it a solid, natural look and the metal doohickeys are nicely hidden by the pots. Initially I bought long, light plastic containers, but these would always start to bulge wide in the middle, making it difficult to remove them. After trying several kinds of plants, I concluded that that spot must be too warm for most succulents, so some of these were moved to other spaces. The agave parviflora is doing great, the aloe is blooming (though I only planted it this winter, so I’m a bit anxious about the hot summer months) and the Cleistocactus strausii has grown so big that it needs its own scaffolding.
Improvements in next version
- better ‘legs’: the metal struts are a bit bendy so if you move the thing you have to shift the legs on the floor so that they’re nicely vertical
- better structural stability: add a cross between front/back legs?
Credits
requirements, design & testing : Febe
purchasing parts & assembly: Arnold
Febe writes 