Hydrangeas - How to Grow & Care for Hydrangea Flowers

Growing hydrangeas successfully starts with the planting process. It's all about timing, location and healthy soil.

When to plant hydrangeas:

Container-purchased plants should be planted in spring or fall. Make sure there is no threat of frost when planting.

Where to plant hydrangeas:

• The best location is one that receives morning sun and afternoon shade. If you live further north, they will tolerate more sun (possibly full sun all day).
• Consider mature size, give it plenty of room to grow.
• Choose an area with excellent drainage. Amend the soil with compost if necessary.
• Don't plant beneath a tree—the root competition and lack of sunlight will prevent them from thriving.
• Avoid planting in exposed areas where gusty winds could snap stems.

How to plant hydrangeas:

• Get your plant off to a healthy start by amending your soil with up to 15% organic matter and an all-purpose slow-release fertilizer (use half of what is recommended).
• Plant slightly higher than they were in the nursery container.
• The planting hole should be 2 to 3 times wider than the root ball to give the roots plenty of room for expansion.
• Gently loosen potbound roots before planting.
• Backfill with the amended soil and water well.
• If planting a grouping, space at least 3 feet apart (more, if planting larger varieties).

Planting hydrangeas in pots:

• Use a bagged potting mix rather than garden soil.
• Mix in a slow-release fertilizer.
• Leave 1 to 2 inches between the top of the soil and the rim of the pot for watering.
• Make sure the pot has drainage holes and has room for the plant to grow.

Learn more about how to grow hydrangeas in pots.

If you wait until spring to prune your mophead hydrangeas (H. macrophylla), be careful not to remove the new buds that are forming. Photo by: Dorling Kindersley ltd / Alamy Stock Photo.

Pruning hydrangeas:

Many don’t need major pruning; most need just enough to keep them tidy by removing old flowers and dead stems, improve the shrub’s structure or shape, or to open it up to let sun and air in.

How and when to prune depends on the type you are growing. You’ll need to determine whether your plant blooms on old wood, new wood, or both before proceeding to prune.

Learn more here: How to Prune Hydrangeas.

Soil:

All like well-drained soil that is rich in organic matter. Soil composition can affect the flower color of H. macrophylla and H. serrata; other varieties can tolerate a range of soil alkalinity.

Learn more here: Changing Hydrangea Color.

Amendments and fertilizer:

Mulch with organic material annually or add a slow-release rose fertilizer (15-10-10) with thorough watering before and after application. Learn more about how to fertilize hydrangeas properly.

Watering hydrangeas:

They like to be kept moist, but not wet—and don’t let them dry out. Container plants may need daily watering. Add mulch to help keep soil moist.

Diseases and pests:

Generally not affected by serious disease or insect problems, however, many species may be susceptible to some bud blight, bacterial wilt, leaf spot, or mildew. Keep an eye out for aphids and mites, and treat as needed. Japanese beetles can be a problem on oakleaf varieties.

Why is my hydrangea not blooming?

This is more common with types that bloom on old wood (last year’s growth). Three common reasons are:

• You may have pruned at the wrong time and inadvertently removed the stems that would have produced flowers.
• The flower buds may have been damaged by a hard frost—cover plants during cold snaps if this may be any issue.
• It could be caused by too much shade or over-fertilizing.

Learn more: 8 Reasons Why Your Hydrangeas Won't Bloom

Hydrangeas can play many roles in the garden, from hedges and screens to container plants, and they especially shine in borders.

• White-flowered varieties create the illusion of snowballs in summer.
• Mass pink and blue types with similarly-colored garden phlox and lilies for a visual confection of candy colors.
• Blue hydrangeas look like sapphires against a gray wall or set alongside a slate patio.
• Bigleaf varieties make imposing container plants—feature a pair in large urns.
• Panicle hydrangeas can be maintained as good-sized “trees” in large pots. Learn how to grow a hydrangea tree.
• Oakleaf hydrangeas are bold and have a coarse texture that lends visual strength to shrub borders and woodland plantings.

See what to plant with your hydrangeas: 20 Best Companion Plants for Hydrangeas