public void update(float delta) {
        for (Plant plant : this.plants) {
            plant.update(delta);
        }
        for (Rock rock : this.rocks) {
            rock.update(delta);
        }
        for (Light light : this.lights) {
            light.update(delta);
        }
        for (Nutrients nutrient : this.nutrients) {
            nutrient.update(delta);
        }
        for (Water water : this.waters) {
            water.update(delta);
        }
    }