Barakta has her boom quite short, to the point that it's possible but a bit fiddly to get a full-sized bottle in and out of the cage (she has to use her right hand, but slide the bottle to the left to clear the chainrings). I keep thinking a
side-entry bottle cage would work better. ICE now do an accessory for mounting the cage in reverse, but tilted up at an angle so it's easier to get in and out. I molished something similar by drilling and bending a piece of steel, but we weren't impressed - your mileage may vary.
Alternative options include clamp-on cages on the back of the seat, or the under-slung brackets molished by loadsabikes for Mrs Miggins of this parish (probably only sensible on one of the higher trikes, and preferably using bottles with covers to keep out the farm slurry). I can't seem to find the thread with the photo...
My general preference is for a hydration bag solution on recumbents, though I tend to use a bottle for shorter rides because they're easier to clean, and live with the inconvenience of having to stop to reach the bottle on the Streetmachine.
The mouthpiece end of hydration hoses can be secured to a convenient place when not in use using rare-earth magnets and heatshrink so it doesn't dangle on the ground or get snagged in wheels or anything. On a mesh seat the fixed magnet can be secured simply by positioning it between the frame and the mesh and re-tensioning.