Zone 6 · Sea Holly
Planting Sea Holly in Zone 6
Eryngium planum
✅ Sea Holly thrives in zone 6 (hardy 4–9)
Can I plant today?
✅ Safe to plant Sea Holly outside
Last frost has passed. Plant in spring in dry, well-drained soil. Steel-blue bracts are striking fresh or dried.
Evaluated for April 27, 2026 ·
Zone's last frost
around April 15
Zone's first frost
around October 15
Bloom window
July – September
Peak bloom
August
Sun required
full sun
Mature height
36"
Spacing
18" apart
Type
perennial
How to plant Sea Holly in zone 6
Plant in spring in dry, well-drained soil. Steel-blue bracts are striking fresh or dried.
Pair with these for continuous bloom
Sea Holly peaks in August. These companions keep your bed in color before and after.
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