How to Grow Oca
Oxalis tuberosa
Oca is a South American tuber crop that forms colourful, tangy tubers in autumn as days shorten. Start tubers in pots indoors in April, plant out after last frost in a warm sheltered spot. Earth up stems regularly like potatoes. Tubers only bulk up from October onwards — harvest after first frost kills the foliage, typically November-December. Sun-sweeten harvested tubers for a few days to improve flavour. Save some tubers to replant next year.
When to Start
Sow indoors 6 weeks before last frost, or direct sow outdoors after frost risk has passed and soil reaches 10°C.
Don't know your frost date? Find it here →
Growth Stages
Approximate days from start
Care Essentials
- Apply a balanced liquid feed every 2-3 weeks from midsummer onwards. Avoid high-nitrogen feeds which promote foliage at the expense of tuber formation.
- Oca is a short-day plant — tubers only form as days shorten in autumn. Maximise the growing season by starting early indoors and planting in a warm, sheltered spot. Earth up stems like potatoes to encourage more tubers.
Growing Conditions
- Min. soil temperature
- 10°C+
Pet Safety
- Sow indoors
- —
- Transplant out
- —
- First harvest
- —
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Spacing & Planting
| Plant spacing | 30 cm |
| Row spacing | 60 cm |
| Sow depth | 5 cm |
| Mature height | 40 cm |
| Mature spread | 30 cm |
Plant tubers 30 cm apart in rows 60 cm apart. Earth up as stems grow, similar to potatoes.
Growing Conditions
| Min. soil temperature | 10°C |
| Base growth temperature | 8°C |
| Photoperiod sensitivity | short day |
Frequently Asked Questions
- How far apart should I plant Oca?
- Plant Oca 30cm apart with 60cm between rows.
- When can I harvest Oca?
- Oca is ready to harvest approximately 180 days after transplanting.
- Is Oca frost hardy?
- Oca is classified as Half Hardy.
