Conroe, Texas · one easy assembly day
Four boxes. Straight cuts. Pilot holes. Screws. Follow the pictures.
v10.0 · July 23, 2026
Build all four cedar shells in one builder visit.
The v10 rotation is two columns: Main + Acid Bed, then Berry Bed + Acid Bed #2. The two beds in each column meet flush with an 8-mil poly moisture break between their end walls. Acid Bed #2 is built now, then covered with cardboard and wood chips until its acid mix and plants arrive in fall 2027. Cool-season greens belong in the Main Bed—there is no separate Greens Bed.
Ask the lumberyard to cut the boards for you: short ends about 44-5/8 inches for this rough cedar (measure yours first) + all 26-inch posts.
Most make cross-cuts free or for about $1 each. Then you need no saw at all. This becomes pure assembly—just screw boards to posts.
Hand them the four tables below. Check every cut with your tape before leaving. See the full McCoy’s sourcing detail for ordering, driveway delivery, and the two questions to ask when you call.
Why 2-inch lumber?
Wood thickness matters more than wood quality.
At 24 inches deep, wet soil pushes about 150 lb per linear foot outward on the bottom boards. Big-box cedar kits use 5/8–3/4-inch boards; they bow visibly in 2–3 years. Two-inch lumber stays straight 10+ years.
2-INCH-THICK ROUGH-SAWN CEDAR.
Smooth (S4S) 2× lumber is usually 1½ inches thick. McCoy’s rough cedar is about 1-11/16 inches thick × 5¾ inches wide, and rough-sawn dimensions can vary from board to board.
Local source: McCoy’s Building Supply stocks the rough cedar 2×6×12 used here and offers lumber delivery. Use the full McCoy’s sourcing detail for the product link, online ordering, driveway delivery, cuts, and the two questions to ask your store.
Call first: “Do you stock 2×12×12 rough cedar, or should I stack 2×6 four high—and do you cut boards and deliver to 77385?”
Fasteners: stainless or coated exterior structural screws only. Plain steel reacts with cedar and leaves black stains.
See Tools and how-to for tool guidance.
All four beds: 4 ft × 12 ft OUTSIDE.
The 12-foot long sides overlap the short ends. With smooth/S4S lumber: 48 in − 1½ in − 1½ in = 45 in. With McCoy’s rough cedar at about 1-11/16 inches thick: 48 in − 1-11/16 in − 1-11/16 in = about 44-5/8 in.
★ ROUGH-SAWN LUMBER VARIES—MEASURE YOUR ACTUAL BOARDS. Before you cut—or tell the yard what to cut—measure the true thickness of one actual side board, double it, and subtract that from 48 inches. That answer is your short-end length.
Don’t lose sleep over a fraction: on a vegetable box, a quarter inch either way is cosmetic, not structural. It only shifts the outside width slightly; the ends still screw to the same 4×4 posts and no soil escapes. This is a garden bed, not cabinetry.
Do not cut ends to 48 inches. That makes the finished bed wider than 4 feet—the classic first-timer mistake.
4×12×24 in · open bottom
Preferred: 2×12 stacked 2 high. Fewer seams.
| Piece | Size | Qty |
|---|---|---|
| Long side course, 2×12 | 12 ft | 4 |
| Short end course, 2×12 | about 44-5/8 in (measure yours) | 4 |
| Corner post, 4×4 | 26 in | 4 |
| Cap rail, 2×4 or 2×6 | 12 ft | 2 |
| Cap rail, 2×4 or 2×6 | 48 in | 2 |
| Exterior structural screws | 3½ in, stainless/coated | 40 |
Alternate: 2×6 stacked 4 high: 8 long + 8 short boards. Everything else stays the same.
4×12×18 in · open bottom
2×6 stacked 3 high ≈ 16½ in actual board height; this is the 18-in nominal bed.
| Piece | Size | Qty |
|---|---|---|
| Long side course, 2×6 | 12 ft | 6 |
| Short end course, 2×6 | about 44-5/8 in (measure yours) | 6 |
| Corner post, 4×4 | 26 in | 4 |
| Cap rail, 2×4 or 2×6 | 12 ft | 2 |
| Cap rail, 2×4 or 2×6 | 48 in | 2 |
| Exterior structural screws | 3½ in, stainless/coated | 56 |
4×12×12 in · open bottom
2×6 stacked 2 high ≈ 11 in finished.
| Piece | Size | Qty |
|---|---|---|
| Long side course, 2×6 | 12 ft | 4 |
| Short end course, 2×6 | about 44-5/8 in (measure yours) | 4 |
| Corner post, 4×4 | 26 in | 4 |
| Cap rail, 2×4 or 2×6 | 12 ft | 2 |
| Cap rail, 2×4 or 2×6 | 48 in | 2 |
| Exterior structural screws | 3½ in, stainless/coated | 40 |
4×12×18 in · open bottom
2×6 stacked 3 high ≈ 16½ in actual board height; this is the 18-in nominal bed. Build the cedar shell with the other three, then cover the empty bed with cardboard + wood chips. Add about 2.7 cu yd of acid mix and plant it in fall 2027.
| Piece | Size | Qty |
|---|---|---|
| Long side course, 2×6 | 12 ft | 6 |
| Short end course, 2×6 | about 44-5/8 in (measure yours) | 6 |
| Corner post, 4×4 | 26 in | 4 |
| Cap rail, 2×4 or 2×6 | 12 ft | 2 |
| Cap rail, 2×4 or 2×6 | 48 in | 2 |
| Exterior structural screws | 3½ in, stainless/coated | 56 |
Sort one bed only.
Mark: LONG · END · POST · CAP. Confirm rough-cedar ends are about 44-5/8 in—or your measured result. Confirm posts = 26 in.
Two pilot holes per board end.
Clamp. Use speed square. Keep holes about 1½ in from edges. Countersink until screw heads will sit flush.
Single most important beginner rule: cedar splits easily. Never drive a screw into cedar without a pilot hole.
Long board → inside 4×4 posts.
Set the first course on flat ground. Board ends flush with post faces. Drive 2 screws per joint.
Measured ends (about 44-5/8 in) fit between long sides.
Clamp end boards to posts. Pre-drill. Countersink. Drive 2 screws per joint.
Measure both diagonals.
Corner-to-corner A. Corner-to-corner B. Nudge one corner until A = B. Equal diagonals = square. That is the whole trick.
Align directly above. No staggering.
Edges flush. Pre-drill every hole. Use 2 screws per joint.
Stop at your bed’s count.
Main Bed: 2 courses of 2×12 (or 4 of 2×6). Acid Bed: 3 courses of 2×6. Berry Bed: 2 courses of 2×6. Acid Bed #2: 3 courses of 2×6.
2×4 or 2×6 around perimeter.
Set over the wall as a sit-on edge. Keep overhang even. Pre-drill, countersink, then fasten into boards/posts.
Two people. Box is heavy.
Carry the empty 4×12 box to its marked spot. Seat the extra 2 inches of each post below grade in the dirt.
Dig away the high side.
Never pack fill under the low side. Packed fill settles; the bed goes crooked later. Set the 4-ft level across the width, then along the length. Re-check both.
Folded 8-mil poly between flush end walls.
In each column, butt the two beds flush end-to-end. Cut a strip from one corner of a 6×8-ft 8-mil black poly tarp, fold it, and sandwich it between the touching end walls. Bury every exposed edge so the moisture break stays neat and kid-safe. Repeat for the second column; save the leftover tarp as a soil-pile cover.
All beds stay open bottom.
They sit on loosened native soil so roots can go deep. Never line the bottom with plastic.
Order and build all four shells in one builder visit. Build one box at a time, then make the two flush joints after the beds are seated and level.
Cedar beds, all four in one order/delivery: $400–900 each
One 6×8-ft 8-mil poly tarp for both joints: about $15
Acid Bed #2 fill + plants, deferred to fall 2027: $170–280
One builder visit:
all four shells now