Garden SurveyorPlanter & Raised Bed Calculator
Structure, fill, drainage, liner plus balcony/roof load checks.
Internal height of the bed. Sleeper beds over 600 mm act as retaining walls and need bracing.
Balcony/roof/podium triggers a structural load check.
9 advanced inputs hidden. Switch to Advanced to fine-tune.
Order what you need for this job
Sharp sand — bulk bags
Building Materials Nationwide
Need ~2 tonne
£55–£85 / tonne · ~£110–£170
See options
Heavy-duty weed-control membrane
Amazon
Need ~17 m²
£15–£40 / roll · ~£15–£40
See options
Ad · Some links are sponsored. We may earn a small commission at no extra cost to you. Suppliers are chosen for fit, not commission.
Compliance
Ground-contact timber must be Use Class 4 (UC4) treated, or it rots at the soil line in 3–5 years.
Why it matters: BS EN 335 UC3 timber is rated for above-ground use only; soil contact demands UC4.
Quantities pre-filled from your calculation (15.0 m²). Partner links — we may earn a small commission if you buy, at no cost to you.
Essentials for this job
Horticultural grit 10 mm — bulk bag
Building Materials Nationwide
Need ~1 tonne for your job
Fine grit for soil conditioning, mulching and potting mixes.
See options at Building Materials Nationwide
Medallion turf — hard-wearing family lawn
Rolawn
Need ~17 m² for your job
High-ryegrass mix for kids, pets and general use. UK-grown, harvested to order.
Check price at RolawnGuide price: £4–£7 / m²(~£68–£119 total)
Indicative · reviewed May 2026
Beautiful Borders / Blended Loam topsoil
Rolawn
Need ~2 tonne for your job
Screened BS3882-compliant topsoil in 1 t bulk bags.
Check price at RolawnGuide price: £45–£80 / tonne(~£90–£160 total)
Indicative · reviewed May 2026
Garden plants — perennials, shrubs & grasses
Crocus
RHS-grade nursery stock in P9–2 L pots — matched to your planting plan.
Check price at CrocusGuide price: £3–£18 / plant
Indicative · reviewed May 2026
Plug plants & garden-ready plants
Gardening Express
Bedding, perennials and climbers by the tray — good value for larger schemes.
Check price at Gardening ExpressGuide price: £2–£12 / plant
Indicative · reviewed May 2026
- Sharp sand — bulk bagsBuilding Materials Nationwide
Screed/bedding sand for slab beds and block-paving courses.
Pre-filled qty: 2 tonne
Guide price: £55–£85 / tonne(~£110–£170 for your job)
Indicative · reviewed May 2026
- Ornamental fine lawn turf — fescue & bentTurf Online
Fine-leaved fescue/browntop bent blend for a close-cut, bowling-green finish.
Pre-filled qty: 17 m2
Guide price: £4–£7 / m²(~£68–£119 for your job)
Indicative · reviewed May 2026
- Shade-tolerant turfTurf Online
Species blended for north-facing and shaded gardens where standard turf struggles.
Pre-filled qty: 17 m2
Guide price: £4–£7 / m²(~£68–£119 for your job)
Indicative · reviewed May 2026
Quantities include a ~10% waste allowance. Guide prices are indicative UK ranges (materials only, inc. VAT) — always confirm with the supplier before ordering.
Prefer to hire a pro?
Compare quotes from vetted local trades using this exact spec.
Ad · Some links are sponsored. We may earn a small commission at no extra cost to you. Suppliers are chosen for fit, not commission.
This app provides general UK guidance and material estimates only. It is not legal, planning, engineering or building-control advice. Always confirm requirements with your local planning authority, building control, utility providers, manufacturers or qualified professionals.
Worked example
Two 2.0 m × 1.0 m raised vegetable beds, 600 mm high, in softwood sleepers.
Inputs
- Size (each)
- 2.0 m × 1.0 m
- Height
- 600 mm
- Number of planters
- 2
- Structure
- Softwood sleepers
- Growing medium
- Vegetable bed mix
| Step | Working | Result |
|---|---|---|
| Usable soil depth | 600 mm height less the drainage layer | 550 mm |
| Fill volume | 2.0 m × 1.0 m × 0.55 m × 2 beds | 2.64 m³ |
| Fill weight | volume × 1.2 t/m³ for a vegetable mix | 3.17 t |
| Sleepers | 3 courses around a 6 m perimeter, × 2 beds | 18 |
| Summer watering | surface area × typical July demand | 26 litres/day |
| What to order | Quantity |
|---|---|
| Fill required | 2.64 m³ |
| Fill (tonnes) | 3.17 t |
| Bulk bags | 4 |
| Mix recipe | Topsoil 1.58 m³ · Compost 0.79 m³ · Well-rotted manure 0.26 m³ |
| Sleepers | 18 |
| Posts | 10 |
| Liner | 12.3 m² |
In short: Order 2.64 m³ of vegetable mix (4 bulk bags), 18 sleepers, 10 posts and 12.3 m² of liner.