Cement is a fine, soft, powdery-type substance. It is made from a mixture of elements that are found in natural materials such as limestone, clay, sand and/or shale. When cement is mixed with water, it can bind sand and gravel into a hard, solid mass called concrete.
Overview. While onions may be welcome in your vegetable garden, they are considered weeds in your lawn. Onion grass, a type of wild onion, often flourishes in yards, particularly in the southeastern region of the U.S. Like most common lawn weeds, onion grass can be eliminated with commercial herbicides and weed killers.tep 2. Cut onion grass very short to prevent flowering. Onion grass reproduces by flowering and seeding. By cutting onion grass to the same height as your lawn grass, you can stop it from spreading.
1 Plant onions as soon as the ground can be worked in the spring, usually late March or April. 2  Make sure temperature doesnât go below 20 degrees F. 3  For sets or transplants, plant the smaller sets 1 inch deep, with 4 to 5 inches between each plant and in rows 12 to 18 inches apart. Select a location with full sun where your onions won't be shaded by other plants. 2  Soil needs to be well-drained, loose, and rich in nitrogen; compact soil affects bulb development. 3  Till in aged manure or fertilizer the fall before planting. 4  Onions are heavy feeders and need constant nourishment to produce big bulbs.