Arundo donax or Giant Reed
How To Grow
Plant in full sunshine in damp soils. This is a riverside native so a damp, fertile soil will give you the best results.
Hardiness
This is generally a USDA zone 6 plant, not appreciating any temperature below 14F or -10C.
If growing it in a colder area, grow in a large container and move indoors after the first frost. Allow the frost to knock it back and let it go dormant. Store cool and damp until spring when it can safely go outdoors (when the temperatures have risen past minimum survival temperatures).
Alternately, move into a cool and sunny spot for the winter before frost. It will slow down in growth but will retain its leaves all winter.
Cut back in the spring to allow it to regrow fresh foliage
Propagation
In the north, where it will not have enough time to flower and set seed before frost knocks it back – division is necessary. This is a big tough root and it will take a determined effort and sharp shovel to cut off a chunk.
In warmer areas, where it sets flower and seed, it can be grown from seed and indeed becomes invasive if really happy.
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