What plant keeps its leaves green all year round
In the city's street trees and indoor green plants, we can always see some plants that keep their leaves green all year. These evergreen plants not only add vitality to the environment but also embody unique survival wisdom. We will analyze the mysteries of these "non-deciduous" plants from two categories: trees and ornamental plants.
Outdoor evergreen trees
Pine family
Plants such as oil pine and cedar adopt needle-like leaf structures, and waxy epidermis can effectively lock in moisture. Their leaf lifespan can reach 3-5 years, and they maintain continuous evergreen by shedding leaves alternately at irregular intervals. These trees are mostly distributed in temperate regions and can still keep their leaves green at -15℃ in winter.
Holly plants
Including varieties such as holly and turtle shell holly, their leather leaves are 0.5-1.2 mm thick. The epidermal cells are closely arranged, combined with the antifreeze substances secreted by the glands, allowing the plants to maintain metabolic activity at -10℃. Each spring, they will replace about 30% of the old leaves.
Podocarpus plants
Represented by short-leaf podocarpus, the leaf lifespan varies from 2 to 8 years. Their well-developed vascular system, combined with the diurnal closure and nocturnal opening of the stomata on the leaf epidermis, greatly reduces water loss. The growth cycle of new leaves and the shedding of old leaves form a dynamic balance.
Indoor evergreen potted plants
Araceae green plants
What plant keeps its leaves green all year round
Variegated yam and monstera deliciosa store water in their fleshy leaves and can achieve annual growth in an indoor environment of 15-28℃. The thickness of their leaf cuticle automatically adjusts with the light intensity, and they can still maintain chlorophyll activity in low light conditions.
Cinnamon ornamental trees
Safe tree leaves contain volatile antibacterial substances that purify the air while maintaining evergreen. Their leaf vein network is dense, with 8-12 secondary veins per square centimeter, ensuring efficient nutrient transport.
Rhizoma plants
Variegated rhizoma plants such as虎眼万年青 store nutrients in underground corms, and their leaf cuticles contain siliceous cells. This structure allows the plants to maintain leaf fullness in dry conditions, combined with the CAM photosynthesis mode to adapt to different lighting environments.
From needle-like trees to ornamental potted plants, evergreen plants maintain their leaf color through multiple mechanisms such as thickening of the cuticle and metabolic regulation. Understanding these characteristics can not only optimize planting plans but also help us choose greening varieties suitable for local climates. With the deepening of plant physiological research, it may be possible to cultivate evergreen plants with stronger adaptability in the future.