When to plant Tomatoes in Phillips County, CO
In Zone 5b (Phillips County), direct-sow Tomatoes between May 11 and June 1 for spring, after the May 4 last-frost mark.
When to Plant Tomatoes in Phillips County, CO
Phillips County, Colorado gardeners: here's your June plan
Your garden in Phillips County, Colorado is working on a schedule, even when you're not. Here's where you should be this June.
-
Start tomatoes indoors
These need a head start before your last frost (May 4). Sow into cells now so you're ready to transplant in a few weeks.
To set up a strong July, finish these tasks
- First harvests: tomatoes
Tomatoes are the most popular home garden crop, available in thousands of varieties from tiny cherries to massive beefsteaks. They are warm-season plants needing full sun.
Phillips County, Colorado is in USDA Zone 5b. The average last spring frost is May 4 and the first fall frost is October 7, giving you a growing season of approximately 156 days.
At an elevation of 5,494 feet, Phillips County receives approximately 21.1 inches of rainfall annually with predominantly loam soil. Summer highs average 87°F, providing good warmth for Tomatoes during the growing season.
Phillips County Soil Profile
Soil Type
Loam
Soil pH
6.5-7.8
Drainage
Well Drained
Tomatoes 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 Phillips County
How your county's soil matches Tomatoes's growing requirements.
Soil pH
Your soil pH (6.5–7.8) is more alkaline than Tomatoes prefers (6.0–7.0). Add sulfur or peat moss to lower pH.
Soil Texture
The loam soil in Phillips County is excellent for Tomatoes — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Tomatoes.
Organic Matter
Organic matter is moderate (2.4%). Annual compost additions will help Tomatoes.
How to Plant Tomatoes
Succession Planting Tomatoes
Sow every 6.9 weeks. Last sowing by Jul 14 to harvest before frost.
Tomatoes Water Budget
Water stress score is 8/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Tomatoes
Tomatoes needs approximately 1.2 inches of water per week (5.2" per month). Here's how your county's rainfall compares month by month.
| Month | Tomatoes Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.5" | 0" | ❄️ Dormant |
| Feb | — | 1.3" | 0" | ❄️ Dormant |
| Mar | — | 1.6" | 0" | ❄️ Dormant |
| Apr | — | 1.9" | 0" | ❄️ Dormant |
| May | 5.2" | 2.8" | 2.4" | 💧 Light watering |
| Jun | 5.2" | 1.5" | 3.7" | 🚿 Regular watering |
| Jul | 5.2" | 1.6" | 3.6" | 🚿 Regular watering |
| Aug | 5.2" | 2.5" | 2.7" | 🚿 Regular watering |
| Sep | 5.2" | 1.7" | 3.5" | 🚿 Regular watering |
| Oct | 5.2" | 1.8" | 3.4" | 🚿 Regular watering |
| Nov | — | 1.7" | 0" | ❄️ Dormant |
| Dec | — | 1.3" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Oct in Phillips County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Tomatoes 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.
Tomatoes Planting Timeline — Phillips County, CO
Tomatoes Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 9 | Mar 9 – Mar 23 |
| Transplant Outdoors | May 18 | May 18 – Jun 1 |
| Direct Sow | May 11 | May 11 – Jun 1 |
| Harvest | July 20 | Jul 20 – Sep 28 |
Plant 0.5" deep · 24" apart · Rows 36" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | — |
| May | Transplant Outdoors Direct Sow |
| June | Transplant Outdoors Direct Sow |
| July | Harvest |
| August | Harvest |
| September | Harvest |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1.2"/week · 2-3 times/week
📅 Days to Maturity
60–85 days
🧪 Soil pH
Needs 6–7 · Your soil: too_alkaline
🗺️ USDA Zone
Zone 5b
📆 Growing Season
156 days in Phillips County
Growing Tips for Tomatoes in Phillips County
Direct sow Tomatoes outdoors after May 04 in Phillips County when soil has warmed and frost danger has passed.
Common pests for Tomatoes in this region include tomato hornworm and aphids. Use row covers early in the season and inspect plants weekly.
Phillips County receives only 21" of rain annually. Tomatoes needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.
General growing tips
Start seeds indoors 6-8 weeks before last frost. Bury transplants deep to encourage rooting along the stem. Provide consistent moisture to prevent blossom end rot and cracking.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Isolate 25 ft between varieties for purity. Use open-pollinated varieties for true-to-type seeds.
Tomatoes in Other Locations
Frequently Asked Questions
When should I plant Tomatoes in Phillips County, CO?
Phillips County is in Zone 5b with an average last frost of May 4. Plan your Tomatoes planting based on this frost date — see the calendar above for exact timing.
What planting zone is Phillips County, CO?
Phillips County, Colorado is in USDA Hardiness Zone 5b. The average last spring frost is May 4 and first fall frost is October 7.
When should I plant Tomatoes in Phillips County, CO?
In Phillips County, CO, plant Tomatoes after the last frost (around May 4) and before the first frost (around October 7). Best results when soil holds above 50°F.
What growing zone is Phillips County, CO for Tomatoes?
Phillips County sits in USDA Zone 5b. Tomatoes grows reliably in zones 3a through 11b, so it's a good fit here.
Can Tomatoes grow in Phillips County's climate?
Yes — Tomatoes grows well in Phillips County's temperate climate. Phillips County averages a 156-day frost-free season, with last frost around May 4 and first frost around October 7.
Your Phillips County Garden Planner — Free
A 22-page printable planner built for Phillips 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.