Gladiolus grandiflorus
Gladiolus × gandavensis
Large-flowered gladioli produce dramatic tall spikes packed with ruffled trumpet flowers in every colour from July to September. The classic exhibition gladiolus beloved of allotment holders and flower arrangers. Half-hardy so corms must be lifted each autumn. Available in hundreds of cultivars in UK garden centres.
Where to plant
Best aspect
Border position
When to plant and expect flowers
Plant
Flowers
How to grow gladiolus grandiflorus
Plant 10-15cm deep from March to May after the last frost. Stake tall varieties. Lift corms after the first frost, dry, and store frost-free. Plant in succession every 2 weeks for continuous flowers. Feed fortnightly with tomato fertiliser.
Soil requirements
Soil type
loam, sand
Moisture
well drained
pH
neutral, alkaline
Aftercare
Allow foliage to die back naturally after flowering. Remove spent flower heads to prevent self-seeding.
Propagation
- Offsets in autumn
- Seed
Wildlife value
Toxicity
This bulb is not known to be toxic to pets or people.
Common problems
- Gladiolus thrips
- Corm rot
- Wind damage to tall spikes
- Earwigs
Similar bulbs to grow
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