Very nice Red, and rare among French Hydrangea French hydrangeas (Hydrangea macrophylla), flower colors indicate the pH of the soil. To maintain the Beautiful Red Hue of this French Mop-head Variety, treat the soil beneath the plant with 1/2 cup garden lime once a year. Grows to 4 feet tall and 4 feet wide. This Hydrangea blooms on old wood, so prune for size only. An Easy plant to Grow and maintain. Plant in any good garden soil in part shade. Keep Moist.
COLOR: In these species the exact colour often mirrors the pH of the soil; acidic soils produce blue flowers, neutral soils produce very pale cream petals, and alkaline soils results in pink or purple. The typically acidic soils of the Pacific Northwest will cause the variable flowers to bloom toward bright true blues and deep purples. For rose red or deep pink flowers add lime to raise the pH and sweeten the soil. Mulching these plants with plant matter, adding Manure, or a half cup of sulfur will raise the acidity in the Hydrangea grows best in partial to bright shade. Although Hydrangeas are not picky about soil, they are not drought tolerant and will grow and flower more prolifically with regular summer watering.