Outdoor bed in SWLA in progress

[CactusSquirrel]

I am building an outdoor bed for cacti and succulents so far I have the grass stripped (more need to go) and a bit of the clay soil removed. The idea came from something I saw on the web of an alpine rock garden that was made in Florida to manage the rain and humidity. The plan is to dig out some of the dirt to lay in a layer of drainage rocks, then put in a border of cinder blocks or large rocks and fill in with a very well draining mix, put the plants in then cover with a layer of decorative rocks. I am still sourcing material for the soil mix. I am in Louisiana in zone 8b. Not terribly cold but can be rainy and humid and cold all at once for a small part of the year. Any suggestions or advice are greatly appreciated. I am new to keeping C&S and have been gardening for only a year otherwise.

[MJPapay]

Here is what I use in my raised beds:

(1) Barrel Cactus mix: (1-part leafmold compost) + (1-part sharp pea-gravel)

(2) Opuntiad mix: (1-part lean topsoil) + (1-part sharp pea-gravel)

by "lean topsoil" I mean "not clayey"

Here's another thing to keep in mind - in general a cactus will have shallow roots, so you don't need lots of cactus mix in a raised bed. What you do need to do is provide them with excellent drainage, and this can be accomplished by placing cobbles of rocks in a pile and putting the cactus mix in and over them. However, most of my raised beds are just lots of cactus mix heaped up, with 3 or 4-inches of pea-gravel as mulch.

[CactusSquirrel]

Is there particular reason for each mix? Do Opuntias not like compost for some reason? or is the pea gravel better since it is not porous? Certainly less of a headache to get pea gravel. My Large Opuntias (robusta, linguiformis, ficus indica) I will be putting in individual locations around the yard and front lawn in some kind of raised boxes. I am just rooting these now but ultimately how much of an area do they need? I don't think I can let them get too enormous but i want them to become as big as possible. Like 2'x2' or 4'x4' boxes?

[CactusSquirrel]

I got some muscle to help with the part my tiny self can't do:





A blank canvas, now for the fun part!

[CactusSquirrel]

The dirt was packed down and landscaping cloth was put down, then a layer of drainage rocks. Then the concrete blocks put around the edge on top to give more height since these blocks are only 6" tall. Right now the cloth is just holding the rocks temporarily. There are rebar pins inside to secure them in place and there will be something bordering on the outside edge.



The ground was gently contoured to follow the already existing paths of drainage and a little drainage moat will follow the contour of the outside edge of the front wall of the bed.

Any comments or suggestions are welcome.

[CactusFanDan]

Looking good so far! What kinds of plants are you going to be putting in there? Any particular species in mind?

[CactusSquirrel]

I have a couple of Trichocereus Grandiflorus, a few different O. Microdaysis, maybe a couple of Gymnos and a few echeverias so far and two Mamillarias. It's only the begining, I'm sure the more I learn the more I will find to put in. I have a few I just got but I need to ID them to see if they can go in.