Oca · Yerevan, Yerevan, Armenia
When to plant oca in Yerevan
Main outdoor window
5 Apr - 3 May
A climate estimate. Check your soil, forecast and cultivar.
Timed from last spring frost
5 April
In Yerevan, on your chosen risk.
Ready to pick
1 Nov - 31 Dec
If you plant at the start of the window.
The average last frost. Half of all years are later than this.
Step by step in Yerevan
Download these planting dates (.ics)
Import into Apple Calendar, Google Calendar or Outlook. Dates use the selected risk level and are planning estimates, not frost alerts.
Each window is a planning range. Check the forecast, soil and cultivar before planting; a later date is not automatically safer in hot or wet conditions.
Plant tubers
5 Apr - 3 May
Around your last frost.
Harvest
1 Nov - 31 Dec
Oca through the year
Against the frost risk in Yerevan
Seasonal context
Rainfall and the growing season in Yerevan
May has the highest average precipitation (60 mm); February has the lowest (16 mm). Compare this pattern with the planting windows and your water supply.
During wetter months, check that beds and containers drain after heavy rain. During drier months, plan how you will keep seeds and new transplants watered. Monthly averages can hide long dry spells and intense storms; they do not show soil moisture, humidity or this week's weather.
Source: NASA POWER, corrected MERRA-2 precipitation, 2001–2020. Values are approximate monthly totals, including the water equivalent of snow, from the nearest 0.5° × 0.625° grid cell. This reference period differs from the temperature record. Rainfall provides context and does not change the calculated planting dates. Method and limitations.
Monthly growing conditions in Yerevan
Compare the planting window with the local temperature pattern. These are historical monthly averages, not this year's forecast or measured soil temperatures. Average frost days do not tell you whether a particular night will freeze.
| Month | Average low | Average high | Frost days |
|---|---|---|---|
| January | -4°C (24.9°F)24.9°F (-4°C) | 5.6°C (42.1°F)42.1°F (5.6°C) | 29.2 |
| February | -2.7°C (27.1°F)27.1°F (-2.7°C) | 8.8°C (47.8°F)47.8°F (8.8°C) | 23.5 |
| March | 1°C (33.8°F)33.8°F (1°C) | 14.1°C (57.3°F)57.3°F (14.1°C) | 11.9 |
| April | 6.1°C (42.9°F)42.9°F (6.1°C) | 20.3°C (68.6°F)68.6°F (20.3°C) | 1.6 |
| May | 10.9°C (51.5°F)51.5°F (10.9°C) | 25.3°C (77.5°F)77.5°F (25.3°C) | 0.0 |
| June | 15.9°C (60.7°F)60.7°F (15.9°C) | 31.4°C (88.5°F)88.5°F (31.4°C) | 0.0 |
| July | 19.6°C (67.3°F)67.3°F (19.6°C) | 34.9°C (94.8°F)94.8°F (34.9°C) | 0.0 |
| August | 19.9°C (67.8°F)67.8°F (19.9°C) | 35.1°C (95.2°F)95.2°F (35.1°C) | 0.0 |
| September | 14.9°C (58.8°F)58.8°F (14.9°C) | 29.6°C (85.3°F)85.3°F (29.6°C) | 0.0 |
| October | 8.8°C (47.8°F)47.8°F (8.8°C) | 22°C (71.6°F)71.6°F (22°C) | 0.2 |
| November | 2.1°C (35.9°F)35.9°F (2.1°C) | 14°C (57.1°F)57.1°F (14°C) | 7.3 |
| December | -2.2°C (28.1°F)28.1°F (-2.2°C) | 7.7°C (45.9°F)45.9°F (7.7°C) | 24.0 |
For oca, also check drainage, sunlight and cultivar requirements. See the rainfall context above; humidity, irrigation and local pest pressure are not calculated.
Local growing check
Before choosing oca for Yerevan
- Oca tuber formation often depends on shortening days. The temperature model does not calculate day-length response: compare the local first damaging frost with the cultivar’s tuber-forming season before relying on a harvest estimate.
- May is the wettest month in the rainfall grid, averaging about 60 mm. Check how your own bed drains and plan watering around actual soil moisture; monthly rain totals are not an irrigation schedule.
The temperature and rainfall tables on this page show the underlying climate estimates. How these suitability checks work · Record what happens in your garden.
Before you plant oca
Use the calendar to plan ahead, then check the conditions in your own garden.
- Measure the soil at sowing depth. Aim for at least 10°C (50°F); the calendar estimates soil warmth from air temperatures and cannot measure your bed.
- Check the local overnight forecast before planting out. Delay planting or keep protection ready if frost is forecast, even after the historical last-frost date.
- Harden off plants raised indoors: gradually expose them to outdoor light, wind and temperature before their final move into the bed.
- Use the maturity range on your seed packet when choosing a variety. Cold, short days and transplant stress can make harvest later than the calendar estimate.
Check short-day tuber formation before trusting a frost window
Choose a documented cultivar and a sunny, workable bed with moisture available. Where the season is marginal, consider practical protection for the late growth period rather than simply sowing much earlier.
Lift carefully after the crop has had time to develop, and save sound tubers under appropriate frost-free storage conditions. Record the start of tuber formation, the first damaging frost and the final yield as separate observations.
What to record this season
How much time elapsed between visible tuber formation and the first damaging frost? Add the cultivar, sowing date and conditions to your growing record so you can compare next season.
Further reading: Plants For A Future: Oxalis tuberosa . General crop guidance; local dates on this site are calculated separately. Source checked 19 September 2026 by Safe to Plant; this is not an expert review.
Plants For A Future compiles botanical and cultivation references. This is general species guidance, not a local field trial or evidence that every cultivar will crop in your climate.
How the dates are calculated and their limits · Keep a growing record · Report a local discrepancy
Why these dates
Choose a documented cultivar and a sunny, workable bed with moisture available. Where the season is marginal, consider practical protection for the late growth period rather than simply sowing much earlier.
Check the named variety and local forecast before exposing young growth. The catalog cold-damage figure is a reference, not a guarantee: plant age, acclimatisation, wind and the duration of a freeze affect damage.
This calendar uses frost-relative offsets as a starting point. Oca are timed with planting out 0 weeks after it, and this page simply resolves those offsets against the frost date computed for Yerevan.
Yerevan is zone 8a, within the crop's general range. This is an initial cold-hardiness check; cultivar, exposure, drainage and unusual winters can still change the outcome.
The median frost-free season here is 220 days, against 180 to 210 days to maturity for this crop counted from sowing. That margin is what decides whether a late sowing is worth attempting.
Also in Yerevan
Other vegetables to time
Growing oca in Yerevan
Can I grow oca in Yerevan?
The calendar estimates a planting window, not a guarantee of success. Oca tuber formation often depends on shortening days. The temperature model does not calculate day-length response: compare the local first damaging frost with the cultivar’s tuber-forming season before relying on a harvest estimate.
When should I plant oca in Yerevan?
Aim for 5 Apr - 3 May in an average year. If you would rather not gamble on the weather, wait until 15 Apr - 13 May - by then frost has finished in nine years out of ten.
When might oca be ready to harvest in Yerevan?
The estimated period is 1 Nov - 31 Dec, based on 180 to 210 days from the modeled planting date. Cultivar, planting material and growing conditions can change this interval; check the plant as well as the calendar.
How much frost will oca tolerate?
Check the named variety and local forecast before exposing young growth. The catalog cold-damage figure is a reference, not a guarantee: plant age, acclimatisation, wind and the duration of a freeze affect damage.