NOVELTY - Plant growth is improved by adding at least one terpene, and organic solvent and/or surfactant to a growth medium of the plant.    USE - A method of improving growth of plant including agronomic plants such as rice, wheat, barley, rye, potato, carrot, sugar beet, bean, pea, chicory, lettuce, turnip, radish, spinach, asparagus, onion, garlic, eggplant, pepper, celery, carrot, squash, pumpkin, zucchini, cucumber, quince, melon, nectarine, apricot, strawberry, grape, pineapple, papaya, mango, banana, soybean, tomato, sorghum and raspberries, banana, soybean, corn (maize), cotton, rape, oilseed rape (including canola), sunflower, alfalfa, clover, sugarcane, and turf; fruits and vegetables, such as banana, blackberry, blueberry, strawberry, and raspberry, cantaloupe, coffee, grapes, honeydew, onion, peas, peppers, sweet corn, tobacco, tomatillo, watermelon, rosaceous fruits (such as apple, peach, pear, cherry and plum) and vegetable brassicas (such as broccoli, cabbage, cauliflower, Brussels sprouts, and kohlrabi), millet; sorghum; currant; avocado; citrus fruits such as oranges, lemons, grapefruit and tangerines, artichoke, nuts such as the walnut and peanut; endive; leek; roots such as arrowroot, beet, turnip, radish, yam, and sweet potato; and beans, woody species, such as pine, poplar and eucalyptus, or mint.    ADVANTAGE - The method utilizes materials non-toxic to humans and non-hazardous which can be applied easily at low cost.    DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for:    (1) a method of preventing erosion comprising adding at least one terpene, and organic solvent and/or surfactant to a growth medium that is at risk of erosion (e.g. hillsides, landscapes areas, road or stream banks, beaches or cleared areas), and growing a plant in the growth medium; and    (2) an erosion control material from grass sod, grass seeding mix, landscape matting having plant seed, hydro-seeding mulch, erosion control mats, erosion control blankets, turf reinforcement matting, and bonded fiber matrix comprising at least one terpene, and organic solvent and/or surfactant.