Onion · Bitlis, Bitlis, Turkey
When to plant onions in Bitlis
Main outdoor window
9-30 Apr
A climate estimate. Check your soil, forecast and cultivar.
Timed from last spring frost
24 April
In Bitlis, on your chosen risk.
Ready to pick
18 Jul - 7 Aug
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 Bitlis
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.
Start indoors
13 Feb - 6 Mar
Ten weeks before your last frost, under cover or on a windowsill.
Sow for overwintering
29 May - 19 Jun
Counting back 134 days from your first frost so the crop matures in time.
Plant out
9-30 Apr
Delayed by a soil-warming estimate derived from historical air temperatures. The frost-only date would be 27 Mar. Measure your soil before planting.
Harvest
18 Jul - 7 Aug
Onions through the year
Against the frost risk in Bitlis
Seasonal context
Rainfall and the growing season in Bitlis
April has the highest average precipitation (88 mm); August has the lowest (3 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 Bitlis
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 | -9.1°C (15.6°F)15.6°F (-9.1°C) | -0.5°C (31.2°F)31.2°F (-0.5°C) | 30.7 |
| February | -7.5°C (18.5°F)18.5°F (-7.5°C) | 1.1°C (33.9°F)33.9°F (1.1°C) | 27.3 |
| March | -2.3°C (27.8°F)27.8°F (-2.3°C) | 6.1°C (43°F)43°F (6.1°C) | 22.7 |
| April | 2.4°C (36.3°F)36.3°F (2.4°C) | 12.4°C (54.4°F)54.4°F (12.4°C) | 6.9 |
| May | 7°C (44.6°F)44.6°F (7°C) | 18.2°C (64.8°F)64.8°F (18.2°C) | 0.2 |
| June | 11.9°C (53.4°F)53.4°F (11.9°C) | 26.2°C (79.2°F)79.2°F (26.2°C) | 0.0 |
| July | 16.1°C (61°F)61°F (16.1°C) | 32.3°C (90.1°F)90.1°F (32.3°C) | 0.0 |
| August | 16.7°C (62.1°F)62.1°F (16.7°C) | 32.3°C (90.2°F)90.2°F (32.3°C) | 0.0 |
| September | 12.1°C (53.7°F)53.7°F (12.1°C) | 26.3°C (79.4°F)79.4°F (26.3°C) | 0.0 |
| October | 6.4°C (43.4°F)43.4°F (6.4°C) | 18.1°C (64.6°F)64.6°F (18.1°C) | 1.7 |
| November | -0.4°C (31.3°F)31.3°F (-0.4°C) | 9.6°C (49.2°F)49.2°F (9.6°C) | 15.6 |
| December | -5.6°C (22°F)22°F (-5.6°C) | 2.8°C (37°F)37°F (2.8°C) | 28.2 |
For onions, 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 onions for Bitlis
- Bulb onions need a cultivar matched to local day length. The temperature calendar does not calculate bulbing response; choose a locally appropriate short-day, intermediate-day or long-day variety before using the dates.
- April is the wettest month in the rainfall grid, averaging about 88 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 onions
Use the calendar to plan ahead, then check the conditions in your own garden.
- Measure the soil at sowing depth. Aim for at least 7°C (44.6°F); the calendar estimates soil warmth from air temperatures and cannot measure your bed.
- Frost tolerance does not make saturated or frozen soil suitable for planting. Wait until the bed can be worked without smearing or compacting it.
- 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.
Match bulb onions to day length and intended storage
Seeds, sets and nursery transplants require different lead times. Check which starting material the packet or supplier's instructions describe before counting backwards from harvest.
Use a sunny bed with free drainage and control weeds while the plants are small. Avoid piling wet soil around developing bulbs or treating extra water as a cure for slow growth.
For storage, let the variety reach its proper maturity and cure sound bulbs in a dry, airy place. Use damaged or thick-necked bulbs first rather than mixing them with long-term storage onions.
Growing in a container
A wide container can grow a small bulb crop, but each onion needs its final spacing. Crowding is more appropriate when intentionally harvesting young green onions.
What to record this season
Which cultivar and starting material produced sound bulbs that stored well? Add the cultivar, sowing date and conditions to your growing record so you can compare next season.
Further reading: RHS onions growing guide · Utah State University: Onions in the Garden . 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.
The RHS guide is written for UK growing conditions. Use its cultivation advice with local cultivar and seasonal guidance; its calendar months are not worldwide recommendations.
How the dates are calculated and their limits · Keep a growing record · Report a local discrepancy
Why these dates
Seeds, sets and nursery transplants require different lead times. Check which starting material the packet or supplier's instructions describe before counting backwards from harvest.
Cold tolerance varies with cultivar, plant age, acclimatisation and the duration of a freeze. A plant surviving frost does not mean its leaves, heads, flowers or developing crop will remain undamaged. Check the forecast and the variety's local advice.
This calendar uses frost-relative offsets as a starting point. Onions are timed from 10 weeks before that frost for an indoor start, with planting out 4 weeks before it, and this page simply resolves those offsets against the frost date computed for Bitlis.
The calendar also applies a soil-warming estimate derived from historical air temperatures. Where that estimate is later than the frost-based date, it delays the window. Soil in your own garden can warm earlier or later; a thermometer at sowing depth is a better final check. Cold, wet conditions can slow germination and increase decay risk.
The median frost-free season here is 191 days, against 100 to 120 days to maturity for this crop counted from planting out. That margin is what decides whether a late sowing is worth attempting.
Also in Bitlis
Other vegetables to time
Growing onions in Bitlis
Can I grow onions in Bitlis?
The calendar estimates a planting window, not a guarantee of success. Bulb onions need a cultivar matched to local day length. The temperature calendar does not calculate bulbing response; choose a locally appropriate short-day, intermediate-day or long-day variety before using the dates.
When should I plant onions in Bitlis?
Aim for 9-30 Apr in an average year. If you would rather not gamble on the weather, wait until 9-30 Apr - by then frost has finished in nine years out of ten.
Can I plant onions earlier in Bitlis?
The historical frost estimate is 27 Mar. For Onions, an air-temperature model estimates soil warmth of about 7°C (44.6°F) around 9 Apr. This is not a soil measurement or a forecast. Check your bed at sowing depth; cold, wet conditions can slow growth and increase decay risk.
When might onions be ready to harvest in Bitlis?
The estimated period is 18 Jul - 7 Aug, based on 100 to 120 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 onions tolerate?
Cold tolerance varies with cultivar, plant age, acclimatisation and the duration of a freeze. A plant surviving frost does not mean its leaves, heads, flowers or developing crop will remain undamaged. Check the forecast and the variety's local advice.