When to plant Lilies in Boone County, IL
Plant Lilies in Boone County, between May 7 and May 21 — the only viable window. Zone 5b's short season (176 frost-free days) rules out a fall crop.
When to Plant Lilies in Boone County, IL
Top priorities for Boone County, Illinois gardeners in July
Here's what deserves your attention in Boone County, Illinois this month. Everything below is tailored to Zone 5b and timed around your local frost dates.
-
Collect lilies at their peak
This is the payoff month. Bring a basket, bring a friend, and get into the beds.
August will be here before you know it — start on
- First harvests: lilies
Lilies (Lilium spp.) are among the most impressive summer-blooming bulbs, delivering bold, upward- or outward-facing trumpet blooms on tall stems from June through August. Asiatic hybrids are the most cold-hardy, earliest to bloom, and easiest to grow; Oriental hybrids bloom later with intensely fragrant, larger flowers. Orienpet (OT) hybrids combine the hardiness of Asiatics with the fragrance and size of Orientals. True lilies (not to be confused with daylilies, which are Hemerocallis) form scaly bulbs that persist and multiply underground, returning reliably each year with increasingly large clumps.
Boone County, Illinois is in USDA Zone 5b. The average last spring frost is April 23 and the first fall frost is October 16, giving you a growing season of approximately 176 days.
At an elevation of 512 feet, Boone County receives approximately 39.9 inches of rainfall annually with predominantly silt loam soil. Summer highs average 83°F, so choose short-season varieties of Lilies to ensure they mature before fall.
Boone County Soil Profile
Soil Type
Silt Loam
Soil pH
6-6.8
Drainage
Well Drained
Lilies Planting Risk Windows
Percentages indicate frost risk at transplant. The 70% safe window means there is a 30% chance of frost after transplant — suitable for cold-hardy crops or gardeners with frost protection. The 90% safe window is best for tender plants.
Soil Compatibility in Boone County
How your county's soil matches Lilies's growing requirements.
Soil pH
Your soil pH (6.0–6.8) overlaps with Lilies's range (6.0–6.5), though not a perfect match.
Soil Texture
The silt loam soil in Boone County is excellent for Lilies — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Lilies.
Organic Matter
Organic matter is moderate (3.8%). Annual compost additions will help Lilies.
How to Plant Lilies
Succession Planting Lilies
Sow every 8 weeks. Last sowing by Jun 18 to harvest before frost.
Lilies Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Lilies
Lilies needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Lilies Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.6" | 0" | ❄️ Dormant |
| Feb | — | 1.5" | 0" | ❄️ Dormant |
| Mar | — | 2.7" | 0" | ❄️ Dormant |
| Apr | 4.3" | 3.4" | 0.9" | 💧 Light watering |
| May | 4.3" | 4.1" | 0.2" | 💧 Light watering |
| Jun | 4.3" | 5.7" | 0" | ✅ Rainfall sufficient |
| Jul | 4.3" | 4.9" | 0" | ✅ Rainfall sufficient |
| Aug | 4.3" | 3.8" | 0.5" | 💧 Light watering |
| Sep | 4.3" | 3.5" | 0.8" | 💧 Light watering |
| Oct | 4.3" | 3.5" | 0.8" | 💧 Light watering |
| Nov | — | 2.9" | 0" | ❄️ Dormant |
| Dec | — | 2.3" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Boone County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Lilies Heat Requirements (GDD)
What are Growing Degree Days (GDD)?
Growing Degree Days measure the total warmth your plants receive during the growing season. Think of it as a "heat bank" — every day above 50°F deposits warmth that helps your plants grow.
Each plant needs a certain amount of accumulated heat to mature. If your county provides more GDD than the plant needs, it's a great fit. If it's close, you may want to choose faster-maturing varieties or start seeds indoors to get a head start.
Lilies Planting Timeline — Boone County, IL
Lilies Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | May 7 | May 7 – May 21 |
| Bloom | July 16 | Jul 16 – Oct 15 |
Plant 5" deep · 12" apart · Rows 18" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | — |
| May | Transplant Outdoors |
| June | — |
| July | Bloom |
| August | Bloom |
| September | Bloom |
| October | Bloom |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1"/week · 1-2 times/week
📅 Days to Maturity
70–120 days
🧪 Soil pH
Needs 6–6.5 · Your soil: acceptable
🗺️ USDA Zone
Zone 5b
📆 Growing Season
176 days in Boone County
Growing Tips for Lilies in Boone County
Direct sow Lilies outdoors after April 23 in Boone County when soil has warmed and frost danger has passed.
General growing tips
Plant bulbs in fall (preferred, September–October) or spring, setting them 3 times their diameter deep (typically 4–6 inches) with the pointed end up. Lilies need excellent drainage — they will rot in wet or heavy clay soils. Site with full sun on stems and blooms but cool, shaded soil at the base (ground cover or shallow-rooted annuals at their feet is ideal). Remove spent blooms but leave stems and foliage until they yellow naturally, as the bulb needs the foliage to photosynthesize and rebuild energy stores. Red lily beetle is a serious pest in the Northeast and Pacific Northwest; inspect plants regularly and hand-pick adults and larvae. Never plant Oriental or Asiatic lilies near cats — all Lilium species are highly toxic to cats. Year 2+ bulbs produce the most stems and largest blooms.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Lilies in Other Locations
Frequently Asked Questions
When should I plant Lilies in Boone County, IL?
Boone County is in Zone 5b with an average last frost of April 23. Plan your Lilies planting based on this frost date — see the calendar above for exact timing.
What planting zone is Boone County, IL?
Boone County, Illinois is in USDA Hardiness Zone 5b. The average last spring frost is April 23 and first fall frost is October 16.
When should I plant Lilies in Boone County, IL?
In Boone County, IL, plant Lilies after the last frost (around April 23) and before the first frost (around October 16). Best results when soil holds above 50°F.
What growing zone is Boone County, IL for Lilies?
Boone County sits in USDA Zone 5b. Lilies grows reliably in zones 3a through 9a, so it's a good fit here.
Can Lilies grow in Boone County's climate?
Yes — Lilies grows well in Boone County's temperate climate. Boone County averages a 176-day frost-free season, with last frost around April 23 and first frost around October 16.
Your Boone County Garden Planner — Free
A 22-page printable planner built for Boone County (Zone 5b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.