store-bought vs homemade potting mix for diy earthbox...HELP
construction on the 30-gallon diy-earthbox-knockoff-sub-irrigated-planters for my fall garden is almost complete, and my attention turns to the potting mix to be contained therein.
i have several containers to fill and am carefully weighing quality and cost. i'm leery of committing to one type of mix or another without some guidance. i'd hate to invest in an inferior mix and end up with a correspondingly inferior harvest.
so, i've scoured the big-box stores and the local nurseries, and these are the options i've come up with. as you can see, i'm looking to avoid mixes with synthetic fertilizers as well as anything from the scotts company:
OPTION 1: jungle-growth premium organic mix w/fertilizer (from big-box store)
ingredients: 55-65% composted pine bark fines, sphagnum peat moss, vermiculite, perlite, charcoal ash, organic fertilizer (did not specify, but inconsequential as i'm adding a fertilizer strip)
OPTION 2: lady bug brand vortex potting soil (it's a local mix)
ingredients: humus & manure compost, steamed cedar flakes, ground rice hulls, texas granite sand, hadite, humates
OPTION 3: garden-ville brand potting soil (another local mix)
ingredients: peat moss, coir, rice hulls, compost, perlite, mill sand, red lava sand, greensand, granite, zeolite, and worm castings
OPTION 4: homemade potting mix,
$76.06 for 20 cu ft (whole batch) or $3.80/cu ft
12 cu ft fafard brand (or premier brand--same price--please tell me which is better) sphagnum peat moss, $19.94
4 cu ft perlite, $19.50
4 cu ft vermiculite, $29.99
2.2 lb (5 cups) espoma garden lime, $1.64
5 lb garden-ville brand worm castings, $4.99
i realize the recommendation for the earthbox and similar sub-irrigated container systems is a potting mix sans compost and sand, and those two ingredients are what worry me about option 2 and option 3, respectively (option 2 is compost-based and option 3 seems to contain a lot of sand).
so what's the verdict? store-bought or homemade? also, are there any changes i should make to my mix recipe if you think i should go that route? i left pine bark fines out of my recipe both because i couldn't locate them and because i'm starting to think that they're more filler than anything else.
PLEASE ADVISE! thanks muchly.