Optimum pH range for growth of major crops name pH Rice 6.0-7.0 Soybean 6.0-7.0 corn 6.0-7.0 potato 4.8-5.4 sunflower 6.0-8.0 sweet potato 5.0-6.0 peanut 5.0-6.0 Cabbage 6.0-7.0 tomato 6.0-7.0 watermelon 6.0-7.0 cucumber 6.0-8.0 apple 6.0-8.0 Peach and pear 6.0-8.0 Centrifuge Tube,Refrigerated Centrifuge,High Speed Centrifuge Rong Tai Biochemical Engineering Co., Ltd. , http://www.shpipette.com