Landscapers have fallen in love with the hydrangea shrub species due to their easy maintenance and the lush color they provide every summer, according to Ohio State University. Use them as hedges or garden accent plants. Provide your backyard hydrangeas with the attentive care they need for optimal foliage growth and the most stunning flower development.
Test your soil pH using a soil test kit from any nursery or garden store. Hydrangeas change color according to acidity of the soil in which they're grown, according to the University of Rhode Island. For the best blue colors, keep the pH between 5.0 and 5.5. For the best pink colors, keep the soil pH between 6.5 and 7.0. The pH can be raised or lowered with various types of lime and phosphates. Consult your regional cooperative extension office to find what's available in your area.
Amend the planting site with 3 to 4 inches of compost worked into the soil surrounding the hydrangea shrub. Follow this with a 3-inch layer of mulch spread on the soil surface. This creates moist soil rich in organic matter, mimicking the natural woodland environment in which Ohio State University says wild hydrangeas grow.
Water the hydrangeas once a week, according to the University of Rhode Island. Use enough water to moisten the dirt to a depth of 1/2 foot.
Fertilize the hydrangea plants to provide them with the nutrients needed to sustain vigorous growth. Spread a general all-purpose fertilizer, like a 5-10-10 or a 10-10-10 granular fertilizer, around the shrub's roots every spring. Apply the fertilizer at a rate of 2 lbs. per 100 square feet.
Prune the hydrangea shrubs every winter when the shrub's leaves fall, according to the United States National Arboretum. Trim off up to 1/3 of the plant's oldest branches. This encourages denser foliar development.