How to Grow Hydrangeas and Change Their Color

Plant hydrangeas in partial shade with well-draining soil, water consistently, and adjust soil pH to change flower color - acidic soil produces blue flowers while alkaline soil creates pink blooms.

1. Find the Perfect Spot. Select a spot with morning sun and afternoon shade. Hydrangeas need 4-6 hours of sunlight but protection from harsh afternoon heat. Ensure good air circulation while avoiding windy areas that can damage the large flower heads.
2. Build the Perfect Bed. Dig a hole twice as wide as the root ball and just as deep. Mix the existing soil with compost or aged manure to improve drainage and fertility. Hydrangeas prefer rich, moist soil that drains well but never becomes waterlogged.
3. Get It in the Ground. Place the hydrangea so the top of the root ball sits level with the surrounding soil. Backfill with your amended soil mixture, water thoroughly, and add a 2-3 inch layer of mulch around the base, keeping it away from the stem.
4. Establish a Watering Rhythm. Provide 1-2 inches of water weekly, soaking the soil deeply rather than frequent shallow watering. Water at the base of the plant to avoid wetting the foliage, which can encourage fungal diseases. Maintain consistent moisture especially during hot weather.
5. Know Your Soil's Secret. Use a soil pH test kit to determine your current soil acidity. The pH level directly affects flower color in most hydrangea varieties. Test in early spring before the growing season begins for the most accurate reading.
6. Unlock the Blues. Lower soil pH to 5.0-5.5 for blue blooms. Apply aluminum sulfate or sulfur to acidify the soil in early spring. Mix 1 tablespoon of aluminum sulfate per gallon of water and apply monthly during the growing season. Results typically appear the following year.
7. Shift to Pink Paradise. Raise soil pH to 6.0-7.0 for pink flowers. Add lime or wood ash to make soil more alkaline. Apply according to package directions in early spring, working it into the top few inches of soil around the plant. Be patient as color changes take time.
8. Feed Them Right. Feed with a balanced 10-10-10 fertilizer in early spring. Avoid high-nitrogen fertilizers which promote leaf growth at the expense of flowers. Apply a second light feeding in early summer if needed, but stop fertilizing by late summer to allow the plant to prepare for winter.
9. Cut With Purpose. Prune immediately after flowering ends, typically in late summer or early fall. Remove spent flower heads and any dead or weak stems. Avoid pruning in spring as you'll remove flower buds. Different hydrangea types have different pruning needs, so identify your variety first.
10. Shelter Them Through Cold. Apply a thicker layer of mulch around the base before the first frost. In colder zones, wrap the plant in burlap or cover with a protective cage filled with leaves. Avoid heavy pruning in fall as the old stems provide winter protection for flower buds.