private void populatePlants() {
	Random ra = new Random();
	Plant plant;
	for (int i = 0; i < plantCount; i++) {
	    int n = ra.nextInt(Plant.NUM_OF_PLANT_TYPES + 1);

	    if (n == 0) {
		++n;
	    }
	    switch (n) {
	    case 1:
		plant = new Plant(Plant.GREEN_PLANT);
		plants.add(plant);
		grid.addPlant(plant);
		break;
	    case 2:
		plant = new Plant(Plant.YELLOW_PLANT);
		plants.add(plant);
		grid.addPlant(plant);
		break;
	    case 3:
		plant = new Plant(Plant.MAGENTA_PLANT);
		plants.add(plant);
		grid.addPlant(plant);
		break;
	    case 4:
		plant = new Plant(Plant.RED_PLANT);
		plants.add(plant);
		grid.addPlant(plant);
		break;
	    default:
		break;
	    }
	}
    }