When to Plant Collard Greens in King County, TX
May in King County, Texas — your action list
If you only do a handful of things in the garden this May, make it these. They're sequenced around your zone's frost timing.
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Begin indoor sowing: collard greens
Give them 6–8 weeks indoors before the last frost and you'll transplant into warm soil with seedlings that are already leaping.
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Bring in the collard greens
Taste as you pick. The first ripe produce is the best feedback loop you'll get all season.
Before June arrives, get these ready
- First harvests: collard greens
Collard greens are a heat-tolerant member of the cabbage family with large, sturdy leaves. They are a Southern staple and one of the most nutritious leafy greens.
King County, Texas is in USDA Zone 8a. The average last spring frost is March 31 and the first fall frost is November 7, giving you a growing season of approximately 221 days.
At an elevation of 3,170 feet, King County receives approximately 60.2 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 99°F, so Collard Greens may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring — great for early planting — but Collard Greens will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Collard Greens root diseases.
King County Soil Profile
Soil Type
Sandy Loam
Soil pH
7.8-8.4
Drainage
Well Drained
Plant 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 King County
How your county's soil matches Collard Greens's growing requirements.
Soil pH
Your soil pH (7.8–8.4) is more alkaline than Collard Greens prefers (6.0–7.0). Add sulfur or peat moss to lower pH.
Soil Texture
Sandy soil in King County warms quickly in spring but drains fast. Collard Greens will need more frequent watering and regular compost additions to retain nutrients.
Organic Matter
Organic matter is low (1.1%). Add 2-3 inches of compost before planting Collard Greens.
How to Plant Collard Greens
Fall planting: Sow 10 weeks before your first frost date for a fall harvest.
Succession Planting Collard Greens
Sow every 6.3 weeks. Last sowing by Aug 24 to harvest before frost.
For a dedicated fall crop, sow by Aug 29.
Plant Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Collard Greens
Collard Greens needs approximately 0.8 inches of water per week (3.5" per month). Here's how your county's rainfall compares month by month.
| Month | Collard Greens Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 4.7" | 0" | ❄️ Dormant |
| Feb | — | 3.2" | 0" | ❄️ Dormant |
| Mar | 3.5" | 3.9" | 0" | ✅ Rainfall sufficient |
| Apr | 3.5" | 2.3" | 1.2" | 💧 Light watering |
| May | 3.5" | 1.5" | 2" | 🚿 Regular watering |
| Jun | 3.5" | 2.2" | 1.3" | 💧 Light watering |
| Jul | 3.5" | 10.4" | 0" | ✅ Rainfall sufficient |
| Aug | 3.5" | 11.5" | 0" | ✅ Rainfall sufficient |
| Sep | 3.5" | 8.1" | 0" | ✅ Rainfall sufficient |
| Oct | 3.5" | 5.7" | 0" | ✅ Rainfall sufficient |
| Nov | 3.5" | 3" | 0.5" | 💧 Light watering |
| Dec | — | 3.7" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Mar–Nov in King County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Collard Greens 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.
Collard Greens Planting Timeline — King County, TX
Collard Greens Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 24 | Feb 24 – Mar 10 |
| Transplant Outdoors | March 31 | Mar 31 – Apr 14 |
| Direct Sow | March 17 | Mar 17 – Apr 7 |
| Harvest | May 26 | May 26 – Jul 28 |
| Fall Sowing | August 29 | Aug 29 – Sep 12 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | Start Indoors Transplant Outdoors Direct Sow |
| April | Transplant Outdoors Direct Sow |
| May | Harvest |
| June | Harvest |
| July | Harvest |
| August | Fall Sowing |
| September | Fall Sowing |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.8"/week · Natural rainfall sufficient
📅 Days to Maturity
55–75 days
🧪 Soil pH
Needs 6–7 · Your soil: too_alkaline
🗺️ USDA Zone
Zone 8a
📆 Growing Season
221 days in King County
Growing Tips for Collard Greens in King County
Direct sow Collard Greens outdoors after March 31 in King County when soil has warmed and frost danger has passed.
Sandy soil in King County dries quickly — mulch Collard Greens with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.
With summer highs reaching 99°F in King County, provide afternoon shade for Collard Greens and water deeply in the morning.
Common pests for Collard Greens in this region include cabbage worm and flea beetles. Use row covers early in the season and inspect plants weekly.
General growing tips
Start seeds indoors or direct sow 4-6 weeks before last frost. Harvest lower leaves first, leaving the growing tip intact. Flavor improves after exposure to frost.
Companion Planting
Good Companions
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Check more plant combinations with our Companion Planting Checker →
Collard Greens in Other Locations
Frequently Asked Questions
When should I plant Collard Greens in King County, TX?
King County is in Zone 8a with an average last frost of March 31. Plan your Collard Greens planting based on this frost date — see the calendar above for exact timing.
What planting zone is King County, TX?
King County, Texas is in USDA Hardiness Zone 8a. The average last spring frost is March 31 and first fall frost is November 7.
Your King County Garden Planner — Free
A 24-page printable planner built for King County (Zone 8a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.