Air column: space within the percussion instrument that determines the pitch. Percussion: sounds produced by striking the instrument with a mallet or stick, or striking one instrument against another. 2. Review the process of forming a hypothesis and making a prediction.
Dig short, shallow rows. The rows should be no more than 1/2 inch (1.5 centimeters) deep and spaced 4 inches (10 centimeters) to 6 inches (15 centimeters) apart. 3. Drop the seeds into the rows. Space the seeds approximately 1 inch (25 millimeters) apart in order to allow the onions enough room to grow and mature.
Preparing the Soil. Soil is best prepared for planting onions by mixing in 1 1/2 inches of compost or by adding 10-20-10 fertilizer in a trench. Dig the trench 4 inches deep, add 1/2 cup of fertilizer for each 10 feet of row, cover with 2 inches of soil and plant your onion sets on top of that. Planting the Bulbs.