When to Plant Gladiolus in Kent County, RI
Kent County, Rhode Island gardeners: here's your June plan
Your garden in Kent County, Rhode Island is working on a schedule, even when you're not. Here's where you should be this June.
July will be here before you know it — start on
- First harvests: gladiolus
Gladiolus (Gladiolus spp.) produce tall, stately spikes of trumpet-shaped blooms in a rich array of colors, making them one of the most popular cut flowers in the world. Each spike carries 12–20 florets that open in succession from bottom to top over 7–10 days. By planting corms every two weeks from last frost through early summer, gardeners create a continuous succession of fresh blooms from midsummer through fall. Corms multiply each season — a single planting becomes a growing collection over the years. Ideal for back-of- border planting, cutting gardens, and mixed summer containers.
Kent County, Rhode Island is in USDA Zone 7a. The average last spring frost is April 23 and the first fall frost is October 20, giving you a growing season of approximately 180 days.
At an elevation of 776 feet, Kent County receives approximately 39.7 inches of rainfall annually with predominantly silt loam soil. Summer highs average 91°F, providing good warmth for Gladiolus during the growing season.
Kent County Soil Profile
Soil Type
Silt Loam
Soil pH
5.2-6.2
Drainage
Well Drained
Gladiolus 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 Kent County
How your county's soil matches Gladiolus's growing requirements.
Soil pH
Your soil pH (5.2–6.2) is more acidic than Gladiolus prefers (6.0–6.5). Add garden lime to raise pH.
Soil Texture
The silt loam soil in Kent County is excellent for Gladiolus — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (3.6%). Annual compost additions will help Gladiolus.
How to Plant Gladiolus
Succession Planting Gladiolus
Sow every 8 weeks. Last sowing by Jul 12 to harvest before frost.
Gladiolus Water Budget
Monthly Watering Guide for Gladiolus
Gladiolus needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Gladiolus Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 3.3" | 0" | ❄️ Dormant |
| Feb | — | 2.7" | 0" | ❄️ Dormant |
| Mar | — | 3.3" | 0" | ❄️ Dormant |
| Apr | 4.3" | 3.3" | 1" | 💧 Light watering |
| May | 4.3" | 4.1" | 0.2" | 💧 Light watering |
| Jun | 4.3" | 3.5" | 0.8" | 💧 Light watering |
| Jul | 4.3" | 3.9" | 0.4" | 💧 Light watering |
| Aug | 4.3" | 3.2" | 1.1" | 💧 Light watering |
| Sep | 4.3" | 2.9" | 1.4" | 💧 Light watering |
| Oct | 4.3" | 3.5" | 0.8" | 💧 Light watering |
| Nov | — | 2.9" | 0" | ❄️ Dormant |
| Dec | — | 3" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Kent County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Gladiolus 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.
Gladiolus Planting Timeline — Kent County, RI
Gladiolus Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | April 23 | Apr 23 – May 7 |
| Direct Sow | April 23 | Apr 23 – May 14 |
| Bloom | July 2 | Jul 2 – Nov 5 |
Plant 5" deep · 5" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Transplant Outdoors Direct Sow |
| May | Transplant Outdoors Direct Sow |
| June | — |
| July | Bloom |
| August | Bloom |
| September | Bloom |
| October | Bloom |
| November | Bloom |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1"/week · Only during dry spells
📅 Days to Maturity
70–100 days
🧪 Soil pH
Needs 6–6.5 · Your soil: too_acidic
🗺️ USDA Zone
Zone 7a
📆 Growing Season
180 days in Kent County
Growing Tips for Gladiolus in Kent County
Direct sow Gladiolus outdoors after April 23 in Kent County when soil has warmed and frost danger has passed.
General growing tips
Plant corms 4–6 inches deep, pointed end up, as soon as soil reaches 60°F after last frost. Space 4–6 inches apart; rows 12 inches apart. Stake or grow through a support grid — tall varieties reach 4–5 feet and tip in wind. Begin succession plantings every 2 weeks through early July for continuous bloom. Water deeply once a week; mulch to conserve moisture and suppress weeds. Cut spikes for vases when the lowest floret just begins to open. After first killing frost (in cold zones), dig corms, let dry for 3–4 weeks in a ventilated spot, remove cormels, and store in mesh bags at 35–50°F. In zones 7b–8a, corms sometimes survive mild winters in ground with heavy mulch; in zones 8b+, in-ground overwintering is reliable.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Gladiolus in Other Locations
Frequently Asked Questions
When should I plant Gladiolus in Kent County, RI?
Kent County is in Zone 7a with an average last frost of April 23. Plan your Gladiolus planting based on this frost date — see the calendar above for exact timing.
What planting zone is Kent County, RI?
Kent County, Rhode Island is in USDA Hardiness Zone 7a. The average last spring frost is April 23 and first fall frost is October 20.
Your Kent County Garden Planner — Free
A 22-page printable planner built for Kent 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.