The answer is: low-growing.
Moss campion (Silene acaulis) is a small mountain wildflower that lives at the high arctic and tundra in the higher mountains of Eurasia and North America.
Moss campion is a low, ground-hugging plant.
Tundra plants (in this example moss campion) have special adaptations to survive the harsh conditions. These plants are small with small leaves and with buds tucked within the foliage for maximum protection.