Planting bulbs for summer growth offers a unique landscape. The large varieties of warm weather annual bulbs come in many species and colored flowers. According to the University of Illinois, perhaps the most important factor in summer bulb planting is the flowerbed preparation. Excellent drainage to the bulb flowerbed is key, as most flowering bulbs will rot in the ground if too much water is left around the delicate tubers.
Break up the soil in the summer bulb flowerbed using the rototiller. Cultivate the soil to a depth of at least 8 inches.
Layer organic material onto the new flowerbed. Apply up to 3 bushels of either a well-rotted compost or peat moss per 100 square feet of the flowerbed. Work the material into the soil with the rototiller to a final depth of 8 inches.
Spread 2 cups of the bone meal and 5 tbsp. of the 10-10-10 soluble fertilizer per every 10 square feet of the flowerbed. Rototill the fertilizers into the soil 8-inches deep.
Plant the summer bulbs according to the nursery instructions. The depth of each variety will depend fully on the species and your particular climate area. A general rule of thumb is to plant the bulbs two times to three times, in depth, the diameter of the bulb. In other words, a 3-inch diameter bulb will be planted 6 inches to 9 inches deep.
Irrigate the bulbs with water. The moisture will remove air from around the bulbs and increase the soil to root contact.
Apply 7 tbsp. of the 10-10-10 soluble fertilizer per 10 square feet when the summer bulbs green leaves emerge from the soil. Split this amount over two or three applications during the summer bulbs growing period.