Snowdrop · Wheaton, Illinois, United States
When to plant snowdrops in Wheaton
Main outdoor window
10-24 Sep
A climate estimate. Check your soil, forecast and cultivar.
Timed from last spring frost
26 April
In Wheaton, on your chosen risk.
First flowers
1 Jan - 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 Wheaton
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 the bulbs
10-24 Sep
Four to six weeks before your first frost, so roots form before the ground cools.
In flower
1 Jan - 31 Mar
Snowdrops through the year
Against the frost risk in Wheaton
Seasonal context
Rainfall and the growing season in Wheaton
May has the highest average precipitation (121 mm); January has the lowest (44 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 Wheaton
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 | -9.8°C (14.4°F)14.4°F (-9.8°C) | -1.5°C (29.3°F)29.3°F (-1.5°C) | 29.4 |
| February | -8.2°C (17.3°F)17.3°F (-8.2°C) | 1.1°C (33.9°F)33.9°F (1.1°C) | 26.6 |
| March | -2.4°C (27.6°F)27.6°F (-2.4°C) | 7.7°C (45.9°F)45.9°F (7.7°C) | 23.1 |
| April | 2.6°C (36.7°F)36.7°F (2.6°C) | 14.5°C (58.1°F)58.1°F (14.5°C) | 8.7 |
| May | 8.8°C (47.8°F)47.8°F (8.8°C) | 20.7°C (69.3°F)69.3°F (20.7°C) | 0.3 |
| June | 14.7°C (58.5°F)58.5°F (14.7°C) | 26.3°C (79.3°F)79.3°F (26.3°C) | 0.0 |
| July | 17.6°C (63.8°F)63.8°F (17.6°C) | 28.7°C (83.6°F)83.6°F (28.7°C) | 0.0 |
| August | 17.2°C (63°F)63°F (17.2°C) | 28.3°C (83°F)83°F (28.3°C) | 0.0 |
| September | 12.9°C (55.2°F)55.2°F (12.9°C) | 24.7°C (76.4°F)76.4°F (24.7°C) | 0.0 |
| October | 5.9°C (42.7°F)42.7°F (5.9°C) | 17°C (62.6°F)62.6°F (17°C) | 3.2 |
| November | -0.7°C (30.7°F)30.7°F (-0.7°C) | 8.4°C (47.2°F)47.2°F (8.4°C) | 18.0 |
| December | -6.3°C (20.6°F)20.6°F (-6.3°C) | 1.4°C (34.5°F)34.5°F (1.4°C) | 27.5 |
For snowdrops, 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 snowdrops for Wheaton
- May is the wettest month in the rainfall grid, averaging about 121 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 snowdrops
Use the calendar to plan ahead, then check the conditions in your own garden.
- Frost tolerance does not make saturated or frozen soil suitable for planting. Wait until the bed can be worked without smearing or compacting it.
- 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.
Dry bulbs or snowdrops in the green?
Choose a position with humus-rich soil that stays moist but drains freely, often under deciduous shrubs or trees. A hot, dry bed is a poor substitute for a cool woodland setting.
Let leaves die back naturally after flowering so the bulb can replenish its reserves. Avoid cutting them with the lawn while they are still green.
A calculated frost window alone cannot establish suitability in a tropical climate. Snowdrops need a seasonal growth and dormancy cycle; ask a local bulb specialist before buying.
Further reading: RHS snowdrop 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
Choose a position with humus-rich soil that stays moist but drains freely, often under deciduous shrubs or trees. A hot, dry bed is a poor substitute for a cool woodland setting.
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.
Snowdrops are anchored to the first autumn frost rather than the last spring one, so the planting window on this page counts backwards from the end of the season in Wheaton instead of forwards from its start.
Wheaton is zone 5b, 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 179 days, against 110 to 160 days to first flower for this crop counted from sowing. That margin is what decides whether a late sowing is worth attempting.
Also in Wheaton
Other flowers to time
Growing snowdrops in Wheaton
Can I grow snowdrops in Wheaton?
The calendar estimates a planting window, not a guarantee of success. May is the wettest month in the rainfall grid, averaging about 121 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 snowdrops in Wheaton?
Aim for 10-24 Sep in an average year. If you would rather not gamble on the weather, wait until 27 Aug - 10 Sep - by then frost has finished in nine years out of ten.
When might snowdrops flower in Wheaton?
The estimated period is 1 Jan - 31 Mar, based on 110 to 160 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 snowdrops 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.