Hydrangea thrives in moist, well-drained soil enriched with organic matter, making it important to improve the soil before planting by adding well-rotted compost or manure.
Choose a spot with partial shade, as full sun can scorch the leaves, especially in warmer climates, while deep shade may reduce flowering.
Regular watering is essential, particularly during dry spells, as these plants dislike drying out. To keep the soil cool and retain moisture, apply a layer of mulch around the base in spring, being careful not to let it touch the stems.
Pruning should be done with care. In early spring, remove any dead or damaged wood, but leave the old flowerheads on over winter to protect the buds below from frost.
For mophead and lacecap cultivars, only prune back to the first pair of strong buds beneath the old flowers, as these types bloom on old wood. If necessary, remove one or two older stems down to the base to encourage new growth, but avoid cutting back the entire plant.
Fertilise in spring with a balanced feed, and for cultivars with colour-dependent blooms, test the soil pH. Adding hydrangea colourant (iron and aluminium salts) can enhance blue flowers in acidic soil, while lime can encourage pinker tones in alkaline conditions. It is best to choose according to the predominant soil conditions for best results on colour.