Cavolo nero · Skokie, Illinois, United States
When to plant cavolo nero in Skokie
Main outdoor window
25 Mar - 15 Apr
A climate estimate. Check your soil, forecast and cultivar.
Timed from last spring frost
4 April
In Skokie, on your chosen risk.
Ready to pick
1 Sep - 31 Mar
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 Skokie
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
21 Feb - 14 Mar
Six weeks before your last frost, under cover or on a windowsill.
Sow direct
25 Mar - 15 Apr
Delayed by a soil-warming estimate derived from historical air temperatures. The frost-only date would be 21 Mar. Measure your soil before planting.
Transplant
25 Mar - 15 Apr
Delayed by a soil-warming estimate derived from historical air temperatures. The frost-only date would be 21 Mar. Measure your soil before planting.
Harvest
1 Sep - 31 Mar
Cavolo nero through the year
Against the frost risk in Skokie
Seasonal context
Rainfall and the growing season in Skokie
May has the highest average precipitation (119 mm); January has the lowest (47 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 Skokie
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 | -4.9°C (23.2°F)23.2°F (-4.9°C) | -0.2°C (31.7°F)31.7°F (-0.2°C) | 25.7 |
| February | -4.5°C (24°F)24°F (-4.5°C) | 0.8°C (33.5°F)33.5°F (0.8°C) | 23.6 |
| March | -0.5°C (31°F)31°F (-0.5°C) | 5.1°C (41.2°F)41.2°F (5.1°C) | 16.9 |
| April | 3.8°C (38.8°F)38.8°F (3.8°C) | 10°C (50°F)50°F (10°C) | 2.7 |
| May | 8.8°C (47.8°F)47.8°F (8.8°C) | 15.2°C (59.3°F)59.3°F (15.2°C) | 0.0 |
| June | 15.1°C (59.1°F)59.1°F (15.1°C) | 21.1°C (70°F)70°F (21.1°C) | 0.0 |
| July | 19.6°C (67.3°F)67.3°F (19.6°C) | 24.9°C (76.8°F)76.8°F (24.9°C) | 0.0 |
| August | 20°C (68.1°F)68.1°F (20°C) | 25.1°C (77.1°F)77.1°F (25.1°C) | 0.0 |
| September | 16.4°C (61.5°F)61.5°F (16.4°C) | 22°C (71.6°F)71.6°F (22°C) | 0.0 |
| October | 9.9°C (49.7°F)49.7°F (9.9°C) | 15.6°C (60°F)60°F (15.6°C) | 0.0 |
| November | 3.4°C (38.2°F)38.2°F (3.4°C) | 8.5°C (47.3°F)47.3°F (8.5°C) | 5.5 |
| December | -1.8°C (28.9°F)28.9°F (-1.8°C) | 2.7°C (36.8°F)36.8°F (2.7°C) | 18.4 |
For cavolo nero, 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 cavolo nero for Skokie
- May is the wettest month in the rainfall grid, averaging about 119 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 cavolo nero
Use the calendar to plan ahead, then check the conditions in your own garden.
- Measure the soil at sowing depth. Aim for at least 4.5°C (40.1°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.
Pick cavolo nero from the lower leaves and preserve the centre
Plant into fertile, drained soil and keep moisture steady while roots establish. Inspect leaf undersides and growing tips for caterpillars, aphids and slug damage; tightly curled leaves can hide problems.
Take usable lower leaves while retaining healthy growth at the top. Avoid stripping a small plant faster than it can replace foliage. Record leaf texture and the point at which a plant becomes too tall, damaged or flowering to remain useful.
What to record this season
How many leaves could be taken regularly without weakening the growing centre? Add the cultivar, sowing date and conditions to your growing record so you can compare next season.
Further reading: RHS kale growing guide . 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 reference is written for UK growing conditions. Use its cultivation advice with local seasonal guidance; UK sowing months are not worldwide planting dates.
How the dates are calculated and their limits · Keep a growing record · Report a local discrepancy
Why these dates
Plant into fertile, drained soil and keep moisture steady while roots establish. Inspect leaf undersides and growing tips for caterpillars, aphids and slug damage; tightly curled leaves can hide problems.
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. Cavolo nero are timed from 6 weeks before that frost for an indoor start, with planting out 2 weeks before it, and this page simply resolves those offsets against the frost date computed for Skokie.
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 227 days, against 60 to 80 days to maturity for this crop counted from sowing. That margin is what decides whether a late sowing is worth attempting.
Also in Skokie
Other vegetables to time
Growing cavolo nero in Skokie
Can I grow cavolo nero in Skokie?
The calendar estimates a planting window, not a guarantee of success. May is the wettest month in the rainfall grid, averaging about 119 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 cavolo nero in Skokie?
Aim for 25 Mar - 15 Apr in an average year. If you would rather not gamble on the weather, wait until 3-24 Apr - by then frost has finished in nine years out of ten.
Can I plant cavolo nero earlier in Skokie?
The historical frost estimate is 21 Mar. For Cavolo nero, an air-temperature model estimates soil warmth of about 4.5°C (40.1°F) around 25 Mar. 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 cavolo nero be ready to harvest in Skokie?
The estimated period is 1 Sep - 31 Mar, based on 60 to 80 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 cavolo nero 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.