When to Plant Celosia in Roy, UT
June in Weber County, Utah — your action list
June is a pivotal month for Weber County, Utah gardens. Focus on these tasks first and you'll set up the rest of the season for success.
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Indoor seed-starting week for celosia
Give them 6–8 weeks indoors before the last frost and you'll transplant into warm soil with seedlings that are already leaping.
A few tasks this June that'll pay off in July
- First harvests: celosia
Celosia (Celosia argentea) encompasses the vivid cockscomb (cristata) and feathery plumed (plumosa) types that explode with color in summer heat. Drought-tolerant and disease-resistant, they thrive in the hottest parts of the season and produce long-lasting blooms both in the garden and as cut or dried flowers. A reliable filler in sunny annual beds.
Roy, Utah is in USDA Zone 7a. The average last spring frost is May 26 and the first fall frost is September 21, giving you a growing season of approximately 118 days.
At an elevation of 6,211 feet, Weber County receives approximately 18.4 inches of rainfall annually with predominantly loam soil. Summer highs average 86°F, providing good warmth for Celosia during the growing season. With low rainfall, drip irrigation is essential for growing Celosia successfully. Mulch heavily to conserve soil moisture.
Roy Soil Profile
Soil Type
Loam
Soil pH
6.6-7.7
Drainage
Well Drained
Celosia 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 Roy
How your county's soil matches Celosia's growing requirements.
Soil pH
Your soil pH (6.6–7.7) is more alkaline than Celosia prefers (6.0–7.0). Add sulfur or peat moss to lower pH.
Soil Texture
The loam soil in Weber County is excellent for Celosia — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.3%). Annual compost additions will help Celosia.
How to Plant Celosia
Succession Planting Celosia
Sow every 6.9 weeks. Last sowing by Jun 23 to harvest before frost.
Celosia Water Budget
Water stress score is 8/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Celosia
Celosia needs approximately 0.5 inches of water per week (2.2" per month). Here's how your county's rainfall compares month by month.
| Month | Celosia Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.3" | 0" | ❄️ Dormant |
| Feb | — | 0.9" | 0" | ❄️ Dormant |
| Mar | — | 1.5" | 0" | ❄️ Dormant |
| Apr | — | 2" | 0" | ❄️ Dormant |
| May | 2.2" | 2.1" | 0.1" | 💧 Light watering |
| Jun | 2.2" | 1.4" | 0.8" | 💧 Light watering |
| Jul | 2.2" | 1.5" | 0.7" | 💧 Light watering |
| Aug | 2.2" | 2.2" | 0" | ✅ Rainfall sufficient |
| Sep | 2.2" | 1.5" | 0.7" | 💧 Light watering |
| Oct | — | 1.5" | 0" | ❄️ Dormant |
| Nov | — | 1.5" | 0" | ❄️ Dormant |
| Dec | — | 1.1" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Sep in Weber County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Celosia 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.
Celosia Planting Timeline — Roy, UT
Celosia Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | April 28 | Apr 28 – May 12 |
| Transplant Outdoors | May 26 | May 26 – Jun 9 |
| Direct Sow | May 26 | May 26 – Jun 16 |
| Bloom | July 28 | Jul 28 – Nov 24 |
Plant 0.1" deep · 9" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Start Indoors |
| May | Start Indoors Transplant Outdoors Direct Sow |
| June | Transplant Outdoors Direct Sow |
| July | Bloom |
| August | Bloom |
| September | Bloom |
| October | Bloom |
| November | Bloom |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.5"/week · Natural rainfall sufficient
📅 Days to Maturity
60–90 days
🧪 Soil pH
Needs 6–7 · Your soil: too_alkaline
🗺️ USDA Zone
Zone 7a
📆 Growing Season
118 days in Weber County
Growing Tips for Celosia in Roy
Direct sow Celosia outdoors after May 26 in Weber County when soil has warmed and frost danger has passed.
Weber County receives only 18" of rain annually. Celosia needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.
General growing tips
Start seeds indoors 4–6 weeks before last frost, or direct-sow after soil warms above 60°F. Does not transplant well from large pots — sow in small cells or direct-sow. Needs full sun and warm soil; cold stress causes stunting. Pinch first bloom to encourage branching. Water at the base; wet foliage encourages fungal issues. Excellent dried flower — harvest before seeds set for the best color retention.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Celosia in Other Locations
Your Weber County Garden Planner — Free
A 22-page printable planner built for Weber 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.