Date 1 AprWeather -Basket 0 kcal (0% of goal)Barrel 100 LFPS 0

Click a raised bed (or use the numbered buttons) to inspect it. Each bed is a real soil-water bucket with its own crop; plants grow with warmth (degree-days), water, nutrients, pests and pollination. Bees, wind and the canal are animated; the numbers on the right are the model.

Alpine Lakeside Kitchen Garden: Water, Warmth and Bees

Run one season (1 April to 27 October) of a terraced kitchen garden above a mountain lake. Balance soil water, nutrients, pollination, pests and compost with real daily equations.

Beds

Garden tools

Live readouts

Soil water, selected bed (mm)

Weather and heat sum

Season result

Runs until day 210. A rain-fed comparison season (same weather, no tools) is shown at the end.

Missions

Event log

Independent numerical checks

Also run outside the browser: node src/check.js (FAO-56 worked example, hand-computed GDD, water balance, analytic aphid logistic).

Educational model: crop parameters, soil values and the energy goal are model values, not agronomic advice. A 17 m² plot covers only a small part of one person's food.

Controls

Drag / one finger: orbit; wheel / pinch: zoom; click a bed to select it; buttons Hero / Iso / Top change camera (keys H, I, T).
Space pause, +/- speed, 1-6 select bed.
Hand watering uses water from the 200 L rain barrel (filled by rain on the roof); canal gates give free gravity irrigation.
Fleece protects seedlings from frost; hives and the flower strip raise fruit set and bring ladybirds against aphids.

The science

Soil water. Each bed is a 0.3 m bucket: dS/dt = P + I − ET_c − D − R (mm per day). Field capacity 0.30, wilting point 0.12, saturation 0.45 m³/m³ (a loam; model values). Drainage D = 0.5 (S − S_fc) above field capacity; the rest above saturation runs off. Water stress K_s = clamp((θ − θ_wp) / (0.5(θ_fc − θ_wp)), 0, 1).

Evaporative demand. Hargreaves: ET₀ = 0.0023 (T_mean + 17.8) √(T_max − T_min) R_a, with R_a from the FAO-56 solar geometry at 46°N; ET_c = K_c ET₀ with simplified crop coefficients. The page reproduces the FAO-56 worked example for R_a (32.2 MJ m−² d−¹).

Growth. Development follows degree-days GDD = Σ max(0, (T_max+T_min)/2 − T_base), so a cool spell delays every stage. Daily biomass ΔB = RUE · 0.48 R_s · f_int · K_s · K_t · K_n · K_pest with R_s from Hargreaves–Samani, a triangular temperature response K_t, a nutrient factor K_n and a pest factor. Yield = B · harvest index · fruit set / dry-matter fraction.

Nutrients. Mineralisation m = k_m · OM · Q₁₀^(T−20)/10 (Q₁₀ = 2); crops take N-P-K in proportion to growth; beans fix part of their nitrogen; compost adds N, P, K and organic matter.

Pollination. Fruit set 1 − (1 − s₀) e^−λV where V is bee visits per flower per day (hives, flower strip, weather) and s₀ the self-pollination baseline (tomato 0.4, beans 0.8, zucchini 0).

Pests. Aphids grow logistically (dA/dt = rA(1 − A/K) − cLA), ladybirds (L) come with flowers; planting the same plant family again in a bed raises r by 40%.

Compost. The heap warms up when C:N is near 30 and moisture near 55%; three days above 55°C and 25 days of age give mature compost.

Honest simplifications. One uniform soil column per bed, no erosion or disease, no shading by buildings, a synthetic weather generator, one crop per bed at a time, and a rough energy goal. Sources (by type): FAO Irrigation and Drainage Paper 56, soil-science textbooks, horticultural extension tables.

Models built with Blender (terrain, house, beds, plants) and rendered with Three.js.