Troubleshooting
Nasturtium 'Alaska' problems — and how to fix them
Nasturtium 'Alaska' (Tropaeolum majus 'Alaska') 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.
All leaves, few flowers
Over-rich soil or feeding produces lush foliage with sparse blooms. Grow lean in poor soil and skip fertiliser.
Blackfly (aphids)
Black aphids cluster densely on stems and shoot tips. Hose off, squash, or grow as a trap crop drawing pests off other plants.
Cabbage white caterpillars
Riddle the leaves with holes, as nasturtium attracts brassica-family pests. Remove caterpillars by hand or net plants to keep foliage clean.
Fading variegation
Heavy shade or very vigorous growth can dilute the leaf marbling. Grow in full sun and lean soil to keep the variegation crisp.
Prevent nasturtium 'alaska' problems before they start
Most nasturtium 'alaska' issues are care-mismatch, not bad luck. Dial in the basics:
- Common nasturtium problems — the species this cultivar belongs to
- What's wrong with my plant? — the diagnosis apps compared
- Nasturtium 'Alaska' watering schedule
- Nasturtium 'Alaska' light requirements
- Best soil mix for nasturtium 'alaska'
- Nasturtium 'Alaska' temperature & humidity
- Full nasturtium 'alaska' care guide
Looking for nasturtium 'alaska' in general rather than its problems? Read the full nasturtium 'alaska' care guide — light, water, soil and feeding.
Nasturtium 'Alaska' problems — FAQ
Why is my nasturtium 'alaska' all leaves, few flowers?
Over-rich soil or feeding produces lush foliage with sparse blooms. Grow lean in poor soil and skip fertiliser.
Why is my nasturtium 'alaska' blackfly (aphids)?
Black aphids cluster densely on stems and shoot tips. Hose off, squash, or grow as a trap crop drawing pests off other plants.
Why is my nasturtium 'alaska' cabbage white caterpillars?
Riddle the leaves with holes, as nasturtium attracts brassica-family pests. Remove caterpillars by hand or net plants to keep foliage clean.
Why is my nasturtium 'alaska' fading variegation?
Heavy shade or very vigorous growth can dilute the leaf marbling. Grow in full sun and lean soil to keep the variegation crisp.