Home & Garden Planning Guide
A great garden starts on paper. This guide covers the four numbers that decide whether a bed succeeds: its square footage, the mulch and soil volume it needs, plant spacing, and the budget. Pair each step with the linked calculator so you buy exactly what you need — no half-empty bags.
Step 1: Measure the Bed
For a rectangle, area = length × width. Most bags and bulk deliveries quote square feet, so measure in feet. Odd shapes? Split them into rectangles and add the pieces, or use the square footage calculator. A 4×8 ft raised bed is 32 sq ft — the workhorse size for beginners.
Step 2: Estimate Mulch & Soil Volume
Volume = area × depth. Depths are usually given in inches, so convert: depth in feet = inches ÷ 12. A 100 sq ft bed at 2 inches of mulch:
100 × (2 ÷ 12) = 16.7 ft³ | ÷ 27 = 0.62 cubic yards
Soil for a raised bed is similar but deeper (often 6–12 inches). The mulch calculator and cubic yards calculator handle both. Buy bulk for beds over ~100 sq ft — it's cheaper than bagged.
Step 3: Space the Plants
Spacing prevents disease and competition. Rough guidance: leafy greens 6–12 in, tomatoes 18–24 in, peppers 12–18 in, shrubs 24–36 in. In a 4×8 bed on a 12-inch grid you fit about 32 plants. Square-foot gardening pushes density higher (up to 16 carrots per square), but watch airflow.
Step 4: Set a Budget
First-build costs dominate: a 4×8 frame needs ~15–20 ft³ of soil mix ($30–$60) plus lumber or a kit ($30–$80). Recurring costs (mulch, seeds, fertilizer) are modest. Tally everything in a budget so the project doesn't surprise you. Container gardens trade soil volume for portability but cost more per plant.
Frequently Asked Questions
How much mulch do I need?
Area × depth (in feet) ÷ 27 = cubic yards. 100 sq ft at 2 in ≈ 0.62 yd³. Use the mulch calculator.
How do I calculate square footage?
Length × width for rectangles; split irregular beds into rectangles and sum, or use the square footage calculator.
How far apart to space plants?
Species-dependent: tomatoes 18–24 in, lettuce 6–12 in, shrubs 24–36 in. Follow the tag.
How do I budget a garden?
Sum soil, mulch, plants, edging/tools; a 4×8 first build runs ~$40–$80 in materials plus soil.