Lawn grid: A modern solution for urban landscape

Grass grid or eco-paving (permeable paver system) — is a type of pavement made up of concrete or plastic blocks with special holes through which grass can grow.

The essence of the grass grid lies in its modular structure, which forms a strong yet permeable surface. These modular elements can be made from two main materials: concrete or plastic.

1. Concrete grass grids are the most common type. They are produced from high-strength concrete and have characteristic cavities — often in the shape of honeycombs, crosses, or rectangles — which are subsequently filled with fertile soil and then seeded with grass.

2. Plastic grass grids are primarily made from recycled or virgin high-density polyethylene (HDPE). They are significantly lighter than concrete counterparts, making transportation and installation much easier. Plastic grids withstand significant temperature fluctuations, and some have a flexible structure that allows them to better adapt to uneven terrain.

The main principle of the grass grid's operation is based on ensuring permeability. Instead of creating a solid, waterproof surface that directs all rainwater to the urban drainage system, the grass grid allows water to gradually seep through the soil-filled holes. This process occurs effectively due to the presence of a specially prepared drainage layer (of gravel, sand) located beneath the grid, which accumulates and filters water before it further penetrates into the lower soil layers.

From an environmental perspective, such a grid helps reduce surface runoff of rainwater, which is one of its most important advantages. Water is absorbed into the soil, reducing the load on drainage systems, preventing flooding and soil erosion. The surface helps to mitigate the "urban heat island" effect, as grass and soil absorb significantly less solar radiation compared to asphalt or concrete.

From a functional standpoint, the grass grid has high strength and load-bearing capacity, allowing for the creation of surfaces suitable for regular vehicle traffic, parking, and use by fire and other services. Drainage prevents the formation of water stagnation on the surface, and the system stabilizes the soil, protecting it from trampling, compaction, and erosion in areas with heavy traffic.

Watering is critically important, especially during the rooting stage in the first 4–6 weeks. If seeds were used, watering should be daily or every other day, keeping the soil consistently moist for successful germination and rooting. For sod, daily watering is necessary until it is fully established, and it is important for water to penetrate deeply into all cells. For already rooted grass, watering becomes less frequent but more abundant, similar to regular lawn care — 2–3 times a week in hot and dry weather. The optimal time for watering is early morning.

Mowing should be done regularly as soon as the grass reaches the desired height. For grass grids, the recommended mowing height is slightly higher than for a perfect lawn, approximately 5–7 cm. This helps protect the grass root system from overheating and mechanical damage, and also promotes better moisture retention in the soil, so it is important to avoid cutting too low.

Due to the limited soil volume in the cells, grass in the grass grid may require additional nutrients. In spring, it is advisable to apply starter fertilizers with a high nitrogen content to stimulate growth and ensure a rich green color. In summer, complex fertilizers can be used as needed. In autumn, be sure to apply fertilizers with increased potassium and phosphorus content, which will help the grass prepare for the winter period and strengthen the root system. It is recommended to use slow-release granular fertilizers to ensure an even and prolonged supply of nutrients, always strictly following the manufacturer's instructions.

Weed control is another important aspect, as weeds compete with the lawn for space, water, and nutrients. Hand weeding is the most effective method for small areas — remove weeds as soon as they appear, especially before they flower and produce seeds. For larger areas, selective herbicides specifically designed for lawns can be used, which kill weeds without harming the grass; however, it is extremely important to carefully read the product instructions and strictly adhere to the recommended dosage.

Over time, the soil in the cells of the grass grid may settle or wash away due to rain or vehicle movement. Therefore, periodically, 1–2 times a year or as needed, it is necessary to top up the cells with a mixture of soil, sand, and compost. Typically, a mixture of 70% sand and 30% compost is used. After topping up, evenly distribute the material with a rake and water to compact it.

Clear the surface of the grass grid from fallen leaves, branches, dirt, and other debris. Clogging the holes prevents water and air from penetrating and can create favorable conditions for weed growth or the development of fungal diseases. For cleaning, you can use rakes, brooms, or blowers.

During operation, it is important to monitor the load and usage. The grass grid is designed to withstand significant loads, but try to distribute vehicle movement evenly across the area to avoid excessive soil compaction in certain places and prevent premature wear of the grid. Avoid prolonged standing of heavy vehicles in one spot, especially in hot weather, as this may cause "burning" of the grass. Heavy construction equipment that may damage the grid structure should also not be used. Continuously monitor the effectiveness of the drainage system located beneath the grass grid. If water stagnates on the surface for an extended period after heavy rain, this may indicate problems with the drainage layer, such as compaction or clogging. In such cases, consultation with a specialist may be necessary.

Regarding winter care, avoid using metal shovels or heavy snow removal machines that can damage the grass or the grid structure itself; it is better to use plastic shovels or lightweight snow removal equipment. Also, if possible, avoid the formation of large, long-lasting snowdrifts in one area, as this may contribute to the grass being smothered.