Hydrangea macrophylla 'Twist‑n‑Shout'
A reblooming lacecap in the Endless Summer series with airy flower plates and red stems.
It blooms on old and new wood for an extended season in suitable sites.
Pink to blue color shift depends on soil pH and aluminum.
Brand lists zone 4 to 9; the plant patent lists zone 5 to 9.
At‑a‑glance
- Group/Class: Bigleaf hydrangea, Lacecap
- Height × spread: 3–5 ft (0.9–1.5 m) × 3–4 ft (0.9–1.2 m)
- Bloom window: early summer to fall; reblooming
- Color & flower form: pink to blue lacecap
- Fragrance: 0 none
- USDA hardiness: zones 5–9
- Breeder / Year / Origin: Michael A. Dirr, 2009, USA
- Awards/registration: S. Plant Patent PP20,176; cultivar ‘PIIHM‑I’
- Cut‑flower notes: stems hold heads; conditioning essential; wilt‑prone if stems dry
- Pet safety: avoid
How it differs
- Lacecap form for a lighter look.
- Reblooms on old and new wood.
- Red stems and notable fall color.
Strengths
- Long bloom window
- Distinctive flower form
- Good stem strength
Care in one minute
- Light: morning sun, afternoon shade.
- Soil: organic, well drained; adjust pH for color.
- Water weekly; mulch 2–3 in (5–8 cm).
- Deadhead; avoid hard pruning; protect lower buds in cold regions.
Watch‑outs
- Hardiness listings differ; protect in zone 4
- Needs steady moisture in heat
- Blue requires acidic soil with aluminum
Best uses (tags)
- borders
- cutting
- shade‑tolerant
- long season
Provenance note
Registered as ‘PIIHM‑I’ and patented in 2009. Parentage includes ‘Penny Mac’ crossed with ‘Lady in Red’.
References
U.S. Plant Patent — ‘PIIHM‑I’ PP20,176
NC State Extension — Hydrangea macrophylla species
ASPCA — Hydrangea toxicity
Written by: Your Flowers Guide editorial team
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