Hydrangeas vary largely in terms of size and shape, but all types are bold plants with large flowers. Gardeners often plant them as a specimen plant or along a border. Most hydrangeas can overwinter down to USDA Hardiness Zone 4, where the temperature stays above -30 degrees Fahrenheit, but some are more and some are less hardy. Planting and feeding this shrub correctly will go a long way in keeping it healthy.
Choose an appropriate site to plant the hydrangea. Look for an area with full to partial sun and loamy well-drained soil. On the most part the shrubs will be fuller when in the sun. Choose a spot away from large plants which may compete for water and nutrients.
Dig into the soil to a depth of 12 inches with a spade, breaking up clumps of soil and tossing out rocks. Mix 1 to 2 inches of organic compost into the soil for a little extra fertility. This will also keep the pH slightly acidic, which the hydrangea likes.
Dig a hole twice the width of the root ball and at a depth the same height as the root ball. Place the hydrangea shrub upright in the hole. Backfill the soil around the roots and tamp down around the base of the plant firmly.
Water deeply and slowly. This will help settle the soil around the roots. Place a 2- to 3-inch layer of mulch around the plant to keep the roots moist and cool.
Obtain a complete fertilizer in early spring. Look for a package marked 10-10-10 (10 percent nitrogen, 10 percent phosphorus and 10 percent potassium). The remaining percentage of the fertilizer consists of other nutrients and filler materials.
Spread the fertilizer evenly around the hydrangeas by hand. These plants require 2 pounds of feed per 100 square feet.
Water deeply and slowly immediately after spreading the fertilizer. This will help it sink into the soil and activate more quickly.