ModelCalcs.uk
Vegetation Calculator — Grass, Foliage & Trees
Plan static grass, foliage, tree and ground cover quantities for your diorama scene.
Calculate tree count for the scene
How We Calculate This
The calculator estimates vegetation material quantities based on your base area, desired coverage percentage, and vegetation density setting. The vegetated area = base length × width × coverage %, then each material rate is multiplied by the density factor (sparse ×0.5, moderate ×1.0, dense ×1.5).
Estimates
- Static grass: ~0.05 g per cm² at moderate density (a thick coat; real bags run ~0.026–0.05 g/cm², e.g. a 5 g bag covers roughly 30 sq in / 193 cm²)
- Foliage sheets: assumes ~30% of the vegetated area needs foliage mat, and one nominal 15×15 cm sheet covers ~225 cm² (off-the-shelf mats such as Woodland Scenics run 585–645 cm², so this errs on ordering slightly more)
- Ground cover: ~0.03 g per cm² of loose scatter at moderate density
- Tufts: approximately 1 per 10 cm²
These per-cm² rates are typical-application estimates from hobby coverage data, not exact manufacturer figures — treat the output as a shopping-list starting point and adjust to taste.
Frequently Asked Questions
At 1:35 scale, 2mm grass represents short lawn, 4-6mm is overgrown grass, and 8-12mm is tall weeds or crops. Scale down proportionally for smaller scales. Mix lengths for a more realistic look.
Apply PVA glue to the area, then use a static grass applicator (puffer bottle or electric applicator) to make the fibres stand upright. An electric applicator gives the best results as static charge pulls the fibres vertical.
Seafoam (dried plant material) makes excellent tree armatures. Cover with fine foliage or scatter. Ready-made trees from brands like Noch, Woodland Scenics, or MiniNatur save time. Wire armatures with foliage work well for larger scales.
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Last updated: February 2026
All calculations are estimates. Always verify quantities before purchasing materials.