Sweetcorn · Sosnovyy Bor, Leningradskaya Oblast', Russia

When to plant sweetcorn in Sosnovyy Bor

Main outdoor window

13-27 Jun

A climate estimate. Check your soil, forecast and cultivar.

Timed from last spring frost

4 May

In Sosnovyy Bor, on your chosen risk.

Ready to pick

12 Aug - 21 Sep

If you plant at the start of the window.

The average last frost. Half of all years are later than this.

Estimated soil-warming check. The historical frost estimate is 11 May. An air-temperature model suggests soil suitable for sweetcorn may warm to about 15°C (59°F) around 13 June. This is a planning estimate, not a soil measurement. The calendar uses the later date; measure your bed at sowing depth and check the forecast before planting.

Step by step in Sosnovyy Bor

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.

Sow direct

13-27 Jun

Delayed by a soil-warming estimate derived from historical air temperatures. The frost-only date would be 11 May. Measure your soil before planting.

Harvest

12 Aug - 21 Sep

Sow in succession. A single sowing gives you a single glut. Sow a short row every 14 days through the window above and you get a steady supply instead.
Frost tolerance
Tender
Damaged below
0°C (32°F)
Days to maturity
60–100
Min soil temp
15°C (59°F)
Spacing
30 cm
Sowing depth
30 mm (1.2 in)
Sun
Full

Sweetcorn through the year

Against the frost risk in Sosnovyy Bor

Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec

Frost risk Sow direct Harvest Today
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Seasonal context

Rainfall and the growing season in Sosnovyy Bor

August has the highest average precipitation (93 mm); February has the lowest (43 mm). Compare this pattern with the planting windows and your water supply.

Jan 51 mm
Feb 43 mm
Mar 44 mm
Apr 47 mm
May 58 mm
Jun 76 mm
Jul 83 mm
Aug 93 mm
Sep 65 mm
Oct 74 mm
Nov 65 mm
Dec 61 mm

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 Sosnovyy Bor

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.

NASA POWER climate averages, 1995–2024
MonthAverage lowAverage highFrost days
January -9.2°C (15.4°F) -5°C (23°F) 29.5
February -9.5°C (14.9°F) -4.6°C (23.7°F) 27.1
March -5.8°C (21.6°F) -0.6°C (31°F) 29.1
April -0.2°C (31.7°F) 6.4°C (43.6°F) 15.7
May 5.6°C (42°F) 13°C (55.4°F) 1.6
June 11.2°C (52.2°F) 17.9°C (64.2°F) 0.0
July 14.5°C (58°F) 20.7°C (69.3°F) 0.0
August 13.6°C (56.5°F) 19.7°C (67.5°F) 0.0
September 9.2°C (48.6°F) 14.7°C (58.5°F) 0.0
October 3.8°C (38.8°F) 7.6°C (45.7°F) 5.0
November -1.6°C (29.2°F) 1.5°C (34.6°F) 17.9
December -6.2°C (20.8°F) -2.6°C (27.3°F) 27.1

For sweetcorn, 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 sweetcorn for Sosnovyy Bor

  • August is the wettest month in the rainfall grid, averaging about 93 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 sweetcorn

Use the calendar to plan ahead, then check the conditions in your own garden.

  • Measure the soil at sowing depth. Aim for at least 15°C (59°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.
  • 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.

Plan for pollination as well as warmth

Plant a block rather than one long, isolated row to help wind pollination. Poorly filled cobs can be a pollination problem even when the plants look vigorous.

Read the seed supplier’s isolation advice when mixing sweetcorn types. Cross-pollination between incompatible types can change eating quality.

Keep water available during establishment and cob development. Harvest at the variety’s eating stage and use promptly; days-to-maturity figures are a guide, not a guarantee that every cob is ready.

Growing in a container

A single small pot is a poor setup for a full crop. Plan enough plants and root space for effective pollination, or use a bed.

Further reading: RHS sweetcorn growing guide . General crop guidance; local dates on this site are calculated separately. Source checked 18 September 2026 by Safe to Plant; this is not an expert review.

How the dates are calculated and their limits · Keep a growing record · Report a local discrepancy

Why these dates

Plant a block rather than one long, isolated row to help wind pollination. Poorly filled cobs can be a pollination problem even when the plants look vigorous.

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. Sweetcorn are timed for direct sowing 1 weeks after it, and this page simply resolves those offsets against the frost date computed for Sosnovyy Bor.

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 171 days, against 60 to 100 days to maturity for this crop counted from sowing. That margin is what decides whether a late sowing is worth attempting.

See every crop timed for Sosnovyy Bor →

Growing sweetcorn in Sosnovyy Bor

Can I grow sweetcorn in Sosnovyy Bor?

The calendar estimates a planting window, not a guarantee of success. August is the wettest month in the rainfall grid, averaging about 93 mm. Check how your own bed drains and plan watering around actual soil moisture; monthly rain totals are not an irrigation schedule.

When should I plant sweetcorn in Sosnovyy Bor?

Aim for 13-27 Jun in an average year. If you would rather not gamble on the weather, wait until 13-27 Jun - by then frost has finished in nine years out of ten.

Can I plant sweetcorn earlier in Sosnovyy Bor?

The historical frost estimate is 11 May. For Sweetcorn, an air-temperature model estimates soil warmth of about 15°C (59°F) around 13 Jun. 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 sweetcorn be ready to harvest in Sosnovyy Bor?

The estimated period is 12 Aug - 21 Sep, based on 60 to 100 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 sweetcorn 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.