Trampolines are a popular backyard addition, but they often damage the lawn underneath. While a trampoline will not instantly kill the grass, leaving it in one position for an extended time causes severe damage to the turf. The extent of this damage depends on factors like the trampoline’s size, local climate, and the specific grass variety. Most affected lawns suffer a temporary setback that requires intervention to recover rather than dying completely.
How Trampolines Damage Grass
The primary cause of grass decline beneath a trampoline is the deprivation of sunlight, which is necessary for photosynthesis. The large, opaque jumping mat acts like a dense canopy, blocking the light required for the grass blades to produce chlorophyll. This lack of light causes the grass to lose its green pigment, leading to a yellowed or pale appearance as the plant struggles to produce energy and weakens.
Beyond light reduction, the physical presence of the trampoline’s frame and the downward force of jumping compress the soil underneath. This constant weight, concentrated at the leg contact points, significantly reduces the pore space within the soil structure. Soil compaction restricts the flow of oxygen and water to the grass roots, essentially starving them and preventing deep root growth necessary for a healthy plant.
The trampoline mat also creates a microclimate beneath it that is unfavorable for healthy turf growth. The enclosed area traps still air and humidity, which can increase the risk of fungal disease development in the weakened grass. Furthermore, the dark color of the mat absorbs solar radiation, radiating excess heat downward and causing heat stress on the grass blades, especially during summer months.
Minimizing Lawn Damage Through Management
The most effective strategy for preventing grass damage involves the regular, strategic movement of the trampoline. Homeowners should shift the trampoline’s position every two to three days during the peak growing season to ensure the grass receives adequate sunlight. This allows the newly exposed grass to photosynthesize and recover its vigor before being shaded again.
When the trampoline is moved, focus on the immediate recovery of the exposed patch. Lightly watering the area helps rehydrate the grass and soil, which may have been shielded from rainfall or sprinklers. Applying a balanced, water-soluble fertilizer provides readily available nutrients to help the grass quickly restore its density.
For trampolines that sit low to the ground, consider using extensions or risers to increase the height of the frame. Raising the mat allows for better airflow beneath the structure, reducing the trapped humidity and heat that can promote disease. Improved air circulation also helps to dry the grass blades, which further discourages the growth of harmful fungi.
Storing the trampoline during periods of non-use, such as the off-season, provides the best opportunity for full lawn recovery. Removing the frame completely eliminates all sources of damage, including light blockage, soil compaction, and heat trapping. This proactive approach ensures the grass remains healthy and resilient for the next season.
Recovering a Damaged Lawn
Once the trampoline is removed from a severely damaged area, the initial step is to determine if the grass is merely dormant or completely dead. Yellowed grass that still has a firm crown and some green tissue may recover with light and water. However, brown, brittle patches with no sign of life require a more aggressive repair strategy. The first physical task is to relieve the soil compaction caused by the frame’s weight.
To decompact the soil, use a garden fork or a core aerator to puncture the ground, breaking up the tightly packed soil particles. This process restores the pathways for water and oxygen to penetrate the root zone, encouraging surviving grass roots to grow. After aeration, rake the area to remove any dead thatch or debris, creating a clean seedbed for new growth.
Next, overseed the damaged patches with a suitable grass seed blend. A mix containing shade-tolerant varieties, such as fescues, can be beneficial since the area may receive less sunlight than the rest of the lawn. Lightly cover the seeds with a thin layer of topsoil or compost to ensure good seed-to-soil contact and protect them from drying out.
A precise watering regime is then necessary for successful germination and establishment of the new grass. The seeded area must be kept consistently moist—not soggy—with frequent, light watering sessions until the seedlings are visible. Once the new turf is established, transition to a less frequent but deeper watering schedule to encourage strong, deep root systems.