Can you plant an indoor hydrangea outside?
Often, yes. Hydrangeas sold in bloom as gift plants are usually bigleaf types (Hydrangea macrophylla) that have been forced into flower for sale. Many gardeners move them outdoors once the flowers fade, since hydrangeas are woody shrubs that generally grow best outside. Success depends on your climate, because bigleaf hydrangeas vary in cold hardiness and a given plant tag may or may not match your area. Check the label for hardiness information.
When to move it
Wait until the danger of frost has passed and nights are reliably mild. In many regions that is mid to late spring. If your plant fades in winter, keep it indoors in a bright, cool spot, water lightly and plan to move it out when the weather settles.
Hardening off
Indoor plants are used to steady temperatures and low wind. To avoid shock and leaf scorch:
- Place the pot in a shady, sheltered spot outdoors for a few hours.
- Gradually lengthen the time and increase exposure over one to two weeks.
- Bring it in if a late frost or cold snap is forecast.
Plant it in the ground or keep it in a pot
Planting in the ground gives roots room and usually produces a larger shrub. Choose a spot with morning sun and some afternoon shade, with rich, moisture-retentive but well-draining soil. Dig a hole about as deep as the root ball and somewhat wider, set the plant at its original soil level, then water well.
Keeping it in a pot is also possible. Move it to a larger container with drainage holes, because small gift pots dry out quickly. Potted hydrangeas need more frequent watering and winter protection.
Sun, water and soil
Which hydrangeas thrive in full sun varies. Some types, such as panicle hydrangeas, are often described as tolerating more sun than bigleaf types, which tend to prefer morning light and afternoon shade. Hydrangeas are named for water and generally need consistent moisture, particularly in heat. Mulch helps retain it.
Preparing hydrangeas for winter
- Check your plant’s hardiness in your region.
- Mulch the base after the ground begins to cool.
- Potted plants can be moved to an unheated garage, shed or sheltered spot, or wrapped for protection. Do not let the roots freeze solid in a pot.
- Avoid heavy pruning in autumn, as some hydrangeas bloom on old wood and cutting them back could remove next year’s flower buds.
How long will a potted hydrangea last?
Indoors, the flower heads often last several weeks to a couple of months, but the plant tends to struggle in dry, warm rooms long term. Outdoors in a suitable climate, a hydrangea can live for many years. The first year after forcing may bring fewer flowers while it recovers.
Are hydrangeas deer resistant?
Not reliably. Hydrangeas are often listed as occasionally or frequently damaged by deer, depending on the region and pressure. If deer visit your garden, protect the plant with fencing or netting.
Is hydrangea toxic?
Yes, treat it with caution. Hydrangea leaves, flowers and buds are considered mildly to moderately toxic to dogs, cats and people if eaten, and can cause stomach upset such as vomiting and diarrhea. Keep it away from pets and children, and contact a veterinarian, poison center or doctor if any has been eaten.
Related reading
For other pot plants that can move between indoor and outdoor spaces, see campanula and amaryllis.
FAQ
Will my hydrangea bloom again? Possibly, once established, though it may skip the first year.
Can it stay indoors? Not ideal long term.
Is it safe for pets? No, keep it out of reach.