Bupleurum Griffithii Seeds – “Bupleurum rotundifolium ‘Griffithii'”

Bupleurum griffithii is a cool-season filler flower loved for its airy, branching stems and bright lime-green bracts that add movement, texture, and a pop of fresh colour to any bouquet. Though it resembles delicate foliage, it’s actually a flowering plant — the perfect contrast to bold blooms. Extremely versatile and long-lasting, Bupleurum is a must-grow for spring bouquets and early summer harvesting.

🌱 Growing Conditions

✅ Plant Size:
• Height: 60–90 cm
• Width: 25–35 cm
Upright, branching habit with long, elegant stems and yellow-green umbels.

✅ Climate:
• Cool-season annual — thrives in early spring and autumn sowings.
• Best in areas with mild winters and warm springs.
• Heat-sensitive — harvest before peak summer heat.
• Grows well in tunnels if ventilated and not too hot.

✅ Soil Requirements:
• Prefers loamy, well-draining soil enriched with compost.
• pH: 6.0–7.2 (slightly acidic to neutral).
• Avoid waterlogged spots — sensitive to root rot.

✅ Sunlight Needs:
• Full sun to partial shade.
• Needs good light for tall, upright stems.
• In tunnels: ensure enough spacing and airflow to avoid mildew.

🌸 Planting Instructions

✅ Best Planting Time:
• Late summer to early spring (March–August), depending on climate.
• In cold areas: sow in late winter under protection.
• For tunnel production: sow Feb–April and again July–August for staggered spring harvests.

✅ Sowing Seeds:
• Seed Trays: Sow 6–8 weeks before planting out.
• Cold stratify seeds in the fridge for 5–7 days before sowing — improves germination.
• Lightly cover seed, keep moist but not soggy.

✅ Direct Sowing:
• Only in cool, frost-free climates.
• Needs even moisture to establish.

✅ Spacing:
• Space plants 25–30 cm apart.
• Give enough room for branching and airflow.

✅ Germination Time:
• 10–20 days at 15–18°C
• Cooler temps preferred — don’t sow in hot conditions.
• Use a fine spray mist to keep moist during germination.

💧 Watering & Fertilization

✅ Watering:
• Keep moist during germination and seedling phase.
• Once established, water moderately — allow soil to dry slightly between waterings.
• Avoid overwatering — roots dislike soggy conditions.

✅ Fertilization:
• At planting: compost and a light balanced feed (3:1:5 or organic slow-release).
• Optional boost with kelp or seaweed tonic for healthy growth.
• Too much nitrogen = floppy stems and lush, leafy growth.

✅ Mulching:
• Light mulch retains moisture and suppresses weeds.
• Avoid piling mulch against stems.

🐛 Pest & Disease Management

✅ Common Pests:
• Generally pest-free.
• Occasional aphids on tender growth — spray with neem or insecticidal soap if necessary.

✅ Common Diseases:
• Powdery mildew in poor airflow — especially in tunnels or if overcrowded.
• Root rot in wet, heavy soils.
• Prevent issues with good spacing, ventilation, and well-drained soil.

🌼 Flowering & Maintenance

✅ Bloom Time:
• Flowers 60–90 days after sowing.
• Best bloom window: late spring to early summer.
• Succession sow every 3–4 weeks for longer season.

✅ Deadheading & Pruning:
• Regular harvesting encourages more stems.
• No need to deadhead if growing for cut flowers.
• Remove yellowing lower leaves for cleaner bunches.

✅ Fragrance:
• Mild, green herbal scent — not prominent.
• Grown for form and colour, not fragrance.

🌿 Garden Uses & Companion Planting

✅ Companion Plants:
• Gorgeous filler for spring bloomers like ranunculus, larkspur, snapdragons, calendula, and poppies.
• Pairs well with more structured flowers like dahlias and lisianthus for late spring successions.
• Contrasts beautifully with deep purples, pinks, and oranges.

✅ Best Uses:
• Fresh cut flowers — airy filler with striking chartreuse tones.
• Dries well — great addition to preserved bouquets.
• Wildflower-style beds, naturalistic plantings, and pollinator gardens.
• Adds movement and texture to borders.

💥 Why Grow Bupleurum griffithii?

✔️ Superb Spring Filler – Adds lightness and structure to bouquets
✔️ Fast-Growing & Productive – Cut early and often
✔️ Cool-Season Powerhouse – Thrives when many others don’t
✔️ Low Maintenance – Very little pest/disease pressure
✔️ Dries Well – Holds form and colour for months

Bupleurum griffithii is one of the first fillers ready for spring bouquets — clean, bright, and delightfully feathery. Whether fresh or dried, it brings balance and elegance to every bunch. A must in any florist’s spring tunnel crop!