Hydrangeas are loved for their showy white, pink or blue blossoms and their lush greenery. Twenty-three species of hydrangea exist, although only five are cultivated in the United States. Hydrangeas grown in containers make lovely patio plants and require just a bit more care than those planted in-ground.
Fill your container 1/4 to 1/3 full of potting soil. Remove your hydrangea from its original container and set it in the pot. The top of the plant's soil should sit about 1 to 2 inches below the rim of your pot. Add more soil underneath the plant if it sits lower in the pot.
Fill the container completely with soil, pressing down to remove any air pockets. Water the plant until the potting soil is moist, but not soggy.
Place your pot in a location that receives morning sun and partial afternoon shade, especially in hot climates. Hydrangeas can't tolerate full sun. Choose a location that provides some protection from drying winds.
Water your hydrangea enough to keep it evenly moist. Check it every day by inserting your finger 2 inches down into the soil. The soil should feel moist, but not soggy.
Fertilise your hydrangea once or twice during the growing season. Apply granular fertiliser to the soil according to package directions or insert stick fertilisers into the soil. Hydrangeas don't require a lot of fertiliser and will bloom less if they are fertilised too much.
Prune your container hydrangea. Prune oakleaf hydrangea shortly after flowering. Prune smooth leaf and panicle hydrangea early in spring. Cut out dead branches with hand pruning shears and cut back top branches to maintain shape and control the size of your hydrangea. Also cut dead blossoms (deadheading) to promote more blooming.
Protect your plant from winter cold. Move the plant to a sheltered location and wrap burlap around the pot. Spread 1 to 2 inches of mulch on the soil.
Consult a local nursery expert about hydrangeas that grow well in your area. Many hydrangeas are hardy only to zone 6, so choose a plant that is suited for your area. Annabelle is hardy to zone 4 and requires less moisture than most hydrangeas, making it a good choice for dry, Northern climates. Look for a small variety. Most hydrangeas grow to between 4 and 10 feet. H. syriacus grows to 3 or 4 feet but is only hardy between zones 6 and 8. If possible, purchase a hydrangea while it is in bloom. Garden centres are notorious for mislabelling hydrangeas. Make sure you're getting the plant you want. You may need to transplant your hydrangea eventually to an in-ground location as it outgrows its container.