Succulents aren't unlike many other plants that don't handle wet feet well. In fact, the myth that succulents as a group like to go dry before they're watered was spawned and then perpetuated by growers who use inappropriate soils, soils that hold too much water for too long - too long to suit a very large % of plants we grow in containers for our personal enjoyment, not just succulents.
It doesn't matter what it says on the bag about drainage or what sort of plant the soil is designated as appropriate for, if the soil has a large fraction of small particles (peat, compost, composted forest products, coir, topsoil or garden soil, fine sand ....) it's going to have inherent limitations due to the amount of water it holds and how long it holds it.
Using an appropriate soil, you can grow many succulents in the same pot with plants thought to LIKE soggy soils. The truth is, some plants tolerate soggy soils better than others, but I can't think of a single plant being grown under conventional container culture that can be said to like or prefer soggy soils.
Plant health depends first on root health. A healthy plant isn't possible w/o a healthy root system. A healthy root system needs a soil full of air pockets that provide the oxygen to drive the plant's root function and metabolism. Use a soil that's 50% saturated after you water and you render 50% of the roots impaired - probably more because most of the important roots will be found in the middle of the pot or around the edges, where they CAN get the air and water needed to function.
What to do then? Soils that are made of particles large enough that water is not held between the particles, and are porous so they hold moisture INSIDE of the soil particles solves the issue nicely. The soils I use have either no soggy layer at the bottom (perched water), or very little. They are monkey easy to grow in and tremendously increase the grower's margin for error when it comes to over-watering and inappropriate fertilizing.
I'll show a couple of pictures of the soils I use, and a planting on a piece of lava that has 8-9 different plants growing on it, this last to illustrate that with appropriate drainage and aeration, there really aren't the limitations most growers believe as to the type of plant material that can be grown in the same pot with attention to a few details. The planting on the rock has a number of succulents + hedera (ivy) something or other + Carissa (natal plum).
Al
