The hydrangea comes in both a deciduous or an evergreen variety. It has large, round flowerheads that bloom from early spring to late fall. Hydrangeas range in color from white, blue, red, pink, purple and lavender. The type and amounts of nutrients in the soil usually determine the color of the flowers. Acidic soil usually produces blue flowers. You can also dry the flowers and use them in flower arrangements.
Water your hydrangeas weekly with 2 to 3 inches of water. Keep the soil moist but not soaking. Standing water can cause root rot.
Fertilize your hydrangeas with a 20-20-20 granulated fertilizer early in the spring before the first blooms. Use 2 lbs. of fertilizer for every 100 square feet of soil around your plants.
Test the soil to achieve the desired flower color. For blue flowers the pH should drop to between 5.0 and 5.5. Add 1 tbsp. of aluminum sulfate per gallon of water to the soil. Add 1 cup of dolomitic lime, every three months, to maintain a pink color in your hydrangeas.
Prune the hydrangeas after they have bloomed. Remove any broken or damaged stems.Thin back the previous year's growth to encourage new blooms.
Cover the plant with burlap in the winter after all of the blooms have died. This will protect the hydrangeas from severe cold. Remove the burlap in early spring after the last threat of frost.