sry ,,,,
i see u said u have a creek,,,,
u no there is a great hydro flo sytem u can set up with
2 garden hoses
1 fertilizer bottle (miricle grow lawn fertilizer thingy )
40 feet of polyesterine garden edge( that black rubber stuff 6 inches wide )

place one end of hose in creek facing upstream of course.
place fert. bottle between 2 hoses. run openend of hose to flat field area.
make a c shape using the garden edge 15-20' from open hose.
insert rooted plants within the c and the open hose....i'm sure u se where this is headed...
u will have a hydro system ebb n flo ??.. simply ensure only a trickle of water is flowing threw garden hose and mixing with ferts in bottle ..triickling out to ur bed (plantation)
Bury the garden hose it will work due to constant pressure from stream...
add ferts to container once a week or as u come to visit... nature will take its course with or without the ferts.
trim(top) ur plants BUT do not throw trimmings away simply insert them into ur system they will regenerate FAST... (good oil material later )
always..Imhop...
keeps....