In winter, although multi-span greenhouses receive solar heating, it cannot meet the required temperature conditions for greenhouse production. To ensure optimal production, implement proper thermal protection measures: avoid air leakage by carefully inspecting plastic films, finding holes, and promptly repairing cracks. Ground plastic film should be compacted with soil to prevent cold air entry. Whenever there is no sunlight, cover with insulation materials; uncover when sun appears to reduce heat loss and prevent temperature drop. For weak seedlings with poor cold resistance, build a small plastic shed on bed edges during severe weather for double-layer film protection. Before cold currents arrive, irrigating can increase soil and air temperature because water has large heat capacity. Radiant heating pipes using finned tubes effectively maintain greenhouse heat with stable, efficient performance.