Troubleshooting
Arrowhead 'Kuwai' problems — and how to fix them
Arrowhead 'Kuwai' (Sagittaria trifolia var. sinensis) is generally forgiving once you match its basics, but a few issues come up again and again. Here is what each one looks like, why it happens, and the fix.
Loss of standing water
If the paddy drains the plant stalls and corm yield collapses. Maintain a constant shallow flood throughout the growing season.
Frost on top growth
Foliage is killed by frost, cutting the season short in cool climates. Plant after the last frost and harvest corms before hard freezes, or overwinter them deep in unfrozen mud.
Algae and competing weeds
Open, fertilised water encourages algal blooms and aquatic weeds that compete with young plants. Manage water depth and remove invasive weeds by hand.
Small or bitter corms
Short seasons, low fertility or cool water give small, more astringent tubers. Provide a long warm season, rich mud and steady feeding; always cook the corms to remove bitterness.
Prevent arrowhead 'kuwai' problems before they start
Most arrowhead 'kuwai' issues are care-mismatch, not bad luck. Dial in the basics:
- Common threeleaf arrowhead problems — the species this cultivar belongs to
- What's wrong with my plant? — the diagnosis apps compared
- Arrowhead 'Kuwai' watering schedule
- Arrowhead 'Kuwai' light requirements
- Best soil mix for arrowhead 'kuwai'
- Arrowhead 'Kuwai' temperature & humidity
- Full arrowhead 'kuwai' care guide
Looking for arrowhead 'kuwai' in general rather than its problems? Read the full arrowhead 'kuwai' care guide — light, water, soil and feeding.
Arrowhead 'Kuwai' problems — FAQ
Why is my arrowhead 'kuwai' loss of standing water?
If the paddy drains the plant stalls and corm yield collapses. Maintain a constant shallow flood throughout the growing season.
Why is my arrowhead 'kuwai' frost on top growth?
Foliage is killed by frost, cutting the season short in cool climates. Plant after the last frost and harvest corms before hard freezes, or overwinter them deep in unfrozen mud.
Why is my arrowhead 'kuwai' algae and competing weeds?
Open, fertilised water encourages algal blooms and aquatic weeds that compete with young plants. Manage water depth and remove invasive weeds by hand.
Why is my arrowhead 'kuwai' small or bitter corms?
Short seasons, low fertility or cool water give small, more astringent tubers. Provide a long warm season, rich mud and steady feeding; always cook the corms to remove bitterness.