Quick Guide to Building a Walipini Greenhouse What is a Walipini? An underground greenhouse using earth insulation and solar heat to stay warm year-round. Location Choose a sunny, well-drained spot facing south northern hemisphere, avoiding floods. Size & Shape About 6 ft deep, 2025 ft long, 812 ft wide. North wall higher to tilt roof toward the sun. Dig & Drain Excavate and slope the floor toward drainage like gravel. Insulate Add gravel base and insulate walls with straw or foam. Build Frame & Roof Use wood/metal and transparent angled roof polycarbonate/plastic. Ventilation & Access Add vents to release heat and an insulated door. Optional Thermal Mass Use water barrels or stones to store heat. Prepare Beds & Plant Use compost-rich soil. Grow cold-tolerant plants in winter, warm-season crops in summer. Benefits: Year-round growing, low energy use, cost-effective, protects from weather and pests.