Bamboo Flowering Cycles
Bamboo typically flowers only once, after which the plants die. Some bamboo never set seed even when they flower. All the bamboo in a single grove will usually flower and set seed at once. Some varieties seem to have an alarm clock that causes all plants of a genus – no matter where they are located in the world – to flower and die at the same time.
The intervals at which bamboo flowers and sets seeds vary widely. Here are some examples:
- Phyllostachys bambusoides – 130 years
- Melocanna bambusoides – 30 to 35 years
- Bambusa vulgaris and Bambusa balcooa – never set seeds even when flowering does occur
- Bambusa arundinacea – 30 to 55 years
- Dendrocalamus giganteus – about 75 years.
Bamboo seed doesn’t remain viable very long, so finding a source of fresh seed is important. Specialty nurseries and online sources offer the best options. If you are lucky enough to have or know of someone who has a plant that is setting seed, you can collect it yourself. Simply remove the seed from the flowering panicles when it is dry. Ideally, you should plant immediately.
Since bamboo seed is not readily available and may not germinate well, take every precaution to prevent diseases such as damping off. Use pasteurized soil mix or pour boiling water over individual peat pellets. Thoroughly clean all tools and containers, rinse with dilute bleach and rinse well with plain water – dry in the sun. Discard any discolored or misshapen seeds.
Planting Your Seeds
Bamboo seeds are more likely to germinate if soaked first. Use distilled water warmed to 85°F (30°C) and soak for 24 hours. A pre-germination stimulant, applied before soaking, may also improve germination rates. Plant the seeds in individual peat pellets, flats or individual pots. Lay the seed on top of the planting medium and cover gently with about one-quarter inch of potting soil.
The Growing Environment
Most bamboos are tropical plants. Even temperate-climate bamboo seedlings will do better with warmth and moisture while germinating. Use a mini-greenhouse for small amounts of seeds or cover individual pots with a plastic bag to increase humidity. Remove the cover at least once a day for fresh air. Germinate seeds in a warm environment. Typical germination times range from 10 to 20 days.