Hydrangeas are a quintessential flowering shrub that bring charm and nostalgia to many gardens. With their large, showy blossoms ranging from white to blue to pink, hydrangeas are a favorite among gardeners. However, while all hydrangeas belong to the genus Hydrangea, they don’t all grow and bloom in the same way.
One key difference between hydrangea varieties is whether they bloom on old wood or new wood This refers to whether the flowers form on the previous season’s growth or the current season’s growth Knowing this characteristic helps gardeners properly prune and care for their hydrangeas to maximize flowering,
Hydrangeas that bloom on new wood are ideal choices for colder climates. Since their flower buds form on the current year’s stems, even after a harsh winter the plant will still bloom. Hydrangeas that bloom on old wood may lose their flower buds over winter if they are killed by cold, leaving the plant with no blooms that summer.
For gardeners wanting reliable blooms in chilly areas, focusing on hydrangeas that flower on new wood is a wise strategy. The main types of hydrangea that bloom on new wood are panicle and smooth hydrangeas.
Panicle Hydrangeas
Panicle hydrangeas (Hydrangea paniculata) are known for their large cone-shaped flower heads. They bloom in mid to late summer on the new wood grown each spring. Popular panicle hydrangea varieties include
- Limelight: A very hardy cultivar with bright greenish-white blooms that turn pink in fall. Grows up to 6-8 feet tall.
- Little Lime: A dwarf form of Limelight, reaching 3-5 feet tall.
- Quick Fire: Blooms up to a month earlier than other panicle hydrangeas, with flowers opening white then becoming deep pink. Grows 6-8 feet tall.
- Little Quick Fire: A smaller version growing just 3-5 feet tall.
- Phantom: Has enormous flower heads up to 14 inches across. Blooms are creamy white, turning rose pink. Grows about 6 feet tall.
Panicle hydrangeas thrive with full sun to partial shade. They prefer moist, well-draining soil but are quite drought tolerant when established. These are low maintenance plants, only needing occasional pruning to shape or control size. They make great specimen plants, mass plantings, or privacy hedges.
Smooth Hydrangeas
Smooth hydrangeas (Hydrangea arborescens) get their name from the smooth, non-peeling stems. They produce rounded flower heads consisting of small fertile and larger sterile florets. Well-known smooth hydrangea varieties include:
- Annabelle: The most popular type, with huge white blooms. Grows 4-5 feet tall.
- Incrediball: Produces massive 12-16 inch ball-shaped flower heads. Grows 3-5 feet tall.
- Invincibelle: Offers bright pink blooms and dark green foliage. Grows 3-4 feet tall.
- Lime Rickey: Has fragrant chartreuse to white blooms. A compact variety reaching just 3 feet tall.
Smooth hydrangeas thrive in partial shade and moist, fertile soil. Morning sun with afternoon shade is ideal. These plants are cold hardy to zone 4. Like panicle hydrangeas, smooth hydrangeas bloom on new wood so can be pruned in late winter or early spring. They also tolerate severe pruning. These easy-care shrubs work beautifully in mixed borders and cottage gardens.
Caring for Hydrangeas That Bloom on New Wood
Hydrangeas that flower on new wood are generally quite easy to grow. Here are some tips for keeping them healthy and floriferous:
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Plant in spring: Set out new hydrangeas in spring after the threat of frost has passed. Container-grown plants can be planted anytime in the growing season.
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Water consistently: Give new plantings a thorough soaking 2-3 times per week until established. Mature plants need 1-2 inches of water weekly.
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Add mulch: Maintain a 2-3 inch layer of shredded bark or other organic mulch around the plants to conserve moisture and insulate roots.
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Prune in late winter/early spring: Pruning panicle and smooth hydrangeas at this time removes only last year’s growth, before the current season’s flower buds form. This encourages prolific flowering.
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Fertilize lightly: Apply a balanced fertilizer or compost in early spring. Too much fertility leads to excessive foliage rather than flowers.
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Protect new growth: Avoid disturbing or pruning plants as new growth emerges in spring; new stems are brittle and snap easily when still tender.
Growing hydrangeas that bloom on new wood allows gardeners in all regions to enjoy these beautiful, low-maintenance flowering shrubs. Pay attention to proper planting, site selection, and care for your specific variety. Then sit back and watch the flowers unfold each summer on your panicle or smooth hydrangeas.
Frequently Asked Questions about Hydrangeas That Bloom on New Wood
What types of hydrangea bloom on new wood?
The main hydrangea varieties that bloom on new wood are panicle hydrangeas (Hydrangea paniculata) and smooth hydrangeas (Hydrangea arborescens).
How do you prune hydrangeas that bloom on new wood?
Hydrangeas that bloom on new wood can be pruned in late winter or early spring before new growth begins. Pruning at this time removes only the previous year’s growth so flower buds for the coming summer are not disturbed.
Do oakleaf hydrangeas bloom on old or new wood?
Oakleaf hydrangeas (Hydrangea quercifolia) bloom on old wood. Their flower buds form on the previous season’s stems so pruning should be done immediately after flowering in summer.
Why do some hydrangeas bloom so early?
Certain new hydrangea varieties, called “reblooming” or “remontant” hydrangeas, can produce flowers on both old and new wood. This gives them an extended bloom period, with flowers starting earlier than old wood bloomers. Examples are the Endless Summer and Let’s Dance series.
What other hydrangeas bloom on old wood?
In addition to oakleaf hydrangeas, bigleaf (Hydrangea macrophylla), climbing (Hydrangea anomala), and mountain hydrangeas (Hydrangea serrata) all bloom on old wood. Pruning should be done soon after they flower.
