Recipe 1 — Mel's Mix (premium)
Equal parts compost + peat moss (or coco coir) + coarse vermiculite. Light, weed-free, holds water like a sponge and drains like a colander. It's the Square Foot Gardening standard for a reason.
Per 4×8 bed at 12 in (32 ft³): about 10.7 ft³ of each component ≈ four 3.8 ft³ bales of peat, ~10 bags compost, 2–3 bags vermiculite — $95–140 per bed. Lasts 5–8 years with annual compost top-ups.
Recipe 2 — Budget blend (most popular)
50% topsoil + 30% compost + 20% aeration (perlite or aged bark fines)
Ordered bulk from a landscape yard (“garden blend”), this runs $30–60 per 4×8 bed — roughly a third of Mel's Mix. Slightly heavier and you'll weed an occasional volunteer, but root crops love it and it holds nutrients better than peat-based mixes.
| Recipe | 4×8 × 12 in bed | 5 beds (6 yd³) |
|---|---|---|
| Mel's Mix (bagged) | $95–140 | $475–700 |
| Budget blend (bulk) | $30–60 | $180–360 |
| Layered (logs + blend top) | $20–40 | $100–240 |
Recipe 3 — Layered / hügel beds (deep beds 18 in+)
- Bottom third: logs, branches, corn stalks — they slowly release water and nutrients.
- Middle: leaves, grass clippings, compostable cardboard (smother weeds).
- Top 8–12 inches: real growing mix from recipe 1 or 2. Roots won't venture below for the first season anyway.
What to never use: 100% compost (compacts, burns seedlings), 100% topsoil from bags (dies into concrete in a bed's confines), or fill dirt alone (roots refuse). Raised beds drain — that's their superpower — and straight soil in a box turns into either soup or brick.
Get exact volumes and a Mel's Mix shopping list for your bed size: raised bed soil calculator.