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How to Grow Oca

Oxalis tuberosa

Half Hardy Warm Season Single Harvest

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.

Oxalis tuberosa
Leaftide In your Leaftide garden
Hardiness
Half Hardy
Season
Warm Season
Harvest
Single Harvest
Spacing
30 cm
Height
40 cm
Sow depth
5 cm
Min. soil temperature
10°C+
Start from
Seed
Light
Full sun
Water
Moderate

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

Sow seeds
Day 0
Germination
~14 days
Harvest
~210 days
Seed to harvest
~210 days

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

Cats: Toxic
Dogs: Toxic
Source

Don't know your frost date? Find it here

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.

Try our spacing calculator →

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.

Calculate your harvest date →