When to plant Nasturtium in Randolph County, IL
For Nasturtium in Randolph County, the safe spring window opens around April 11 and closes around May 2. Last expected frost is April 11, first fall frost October 20, giving a 192-day growing season.
When to Plant Nasturtium in Randolph County, IL
Nasturtium (Tropaeolum majus) is a fast-growing annual with distinctive round, lily-pad leaves and bold trumpet-shaped blooms in warm oranges, reds, and yellows. Both the flowers and leaves are edible with a peppery watercress flavor. Planted near vegetables, nasturtiums act as a sacrifice trap-crop, luring aphids away from more valuable plants. They thrive in poor, dry soil — rich conditions produce lush foliage but few flowers.
Randolph County, Illinois is in USDA Zone 7a. The average last spring frost is April 11 and the first fall frost is October 20, giving you a growing season of approximately 192 days.
At an elevation of 501 feet, Randolph County receives approximately 32.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86°F, providing good warmth for Nasturtium during the growing season.
Randolph County Soil Profile
Soil Type
Silt Loam
Soil pH
6.0-7.0
Drainage
Well Drained
Nasturtium Planting Timeline — Randolph County, IL
Nasturtium Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 14 | Mar 14 – Mar 28 |
| Transplant Outdoors | April 11 | Apr 11 – Apr 25 |
| Direct Sow | April 11 | Apr 11 – May 2 |
| Bloom | June 6 | Jun 6 – Oct 10 |
Plant 0.5" deep · 10" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Transplant Outdoors Direct Sow |
| May | Direct Sow |
| June | Bloom |
| July | Bloom |
| August | Bloom |
| September | Bloom |
| October | Bloom |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
Low — drought tolerant
📅 Days to Maturity
55–65 days
🧪 Soil pH
Needs 6–8 · Your soil: N/A
🗺️ USDA Zone
Zone 7a
📆 Growing Season
192 days in Randolph County
Growing Tips for Randolph County
Direct-sow large seeds 1/2 inch deep after last frost; soak seeds overnight to speed germination (7-10 days). Nasturtiums dislike root disturbance so direct sowing is strongly preferred. Avoid fertilizing — poor soil brings the best bloom. Trailing types can cover banks and climb trellises; dwarf types suit containers. In hot climates (zones 9+) plant in fall for winter/spring bloom as plants struggle in peak summer heat.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Nasturtium in Other Locations
Frequently Asked Questions
When should I plant Nasturtium in Randolph County, IL?
Randolph County is in Zone 7a with an average last frost of April 11. Plan your Nasturtium planting based on this frost date — see the calendar above for exact timing.
What planting zone is Randolph County, IL?
Randolph County, Illinois is in USDA Hardiness Zone 7a. The average last spring frost is April 11 and first fall frost is October 20.
When should I plant Nasturtium in Randolph County, IL?
In Randolph County, IL, plant Nasturtium after the last frost (around April 11) and before the first frost (around October 20). Best results when soil holds above 50°F.
What growing zone is Randolph County, IL for Nasturtium?
Randolph County sits in USDA Zone 7a. Nasturtium grows reliably in zones 2a through 11b, so it's a good fit here.
Can Nasturtium grow in Randolph County's climate?
Yes — Nasturtium grows well in Randolph County's temperate climate. Randolph County averages a 192-day frost-free season, with last frost around April 11 and first frost around October 20.
Your Randolph County Garden Planner — Free
A 22-page printable planner built for Randolph County (Zone 7a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.