When to Plant Carrots in Castro County, TX
What to do in May
Your Castro County, Texas garden is entering a new phase. Here's what's on the schedule for May and why each task matters now.
To set up a strong June, finish these tasks
- First harvests: carrots
Carrots are a popular root vegetable available in orange, purple, white, and yellow varieties. They are rich in beta-carotene and have a sweet, earthy flavor.
Castro County, Texas is in USDA Zone 7a. The average last spring frost is April 14 and the first fall frost is October 24, giving you a growing season of approximately 193 days.
At an elevation of 3,838 feet, Castro County receives approximately 47.6 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 95°F, so Carrots may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring — great for early planting — but Carrots will need more frequent watering and organic matter to retain nutrients.
Castro County Soil Profile
Soil Type
Sandy Loam
Soil pH
7.5-8.1
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 Castro County
How your county's soil matches Carrots's growing requirements.
Soil pH
Your soil pH (7.5–8.1) is more alkaline than Carrots prefers (6.0–6.8). Add sulfur or peat moss to lower pH.
Soil Texture
Sandy soil in Castro County warms quickly in spring but drains fast. Carrots will need more frequent watering and regular compost additions to retain nutrients.
Organic Matter
Organic matter is low (1.0%). Add 2-3 inches of compost before planting Carrots.
How to Plant Carrots
Fall planting: Sow 10 weeks before your first frost date for a fall harvest.
Succession Planting Carrots
Sow every 6.9 weeks. Last sowing by Aug 05 to harvest before frost.
For a dedicated fall crop, sow by Aug 15.
Plant Water Budget
Water stress score is 8/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Carrots
Carrots 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 | Carrots Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 3.3" | 0" | ❄️ Dormant |
| Feb | — | 2.7" | 0" | ❄️ Dormant |
| Mar | — | 2.4" | 0" | ❄️ Dormant |
| Apr | 3.5" | 1.7" | 1.8" | 🚿 Regular watering |
| May | 3.5" | 1.2" | 2.3" | 🚿 Regular watering |
| Jun | 3.5" | 1.5" | 2" | 🚿 Regular watering |
| Jul | 3.5" | 8" | 0" | ✅ Rainfall sufficient |
| Aug | 3.5" | 8.9" | 0" | ✅ Rainfall sufficient |
| Sep | 3.5" | 6.8" | 0" | ✅ Rainfall sufficient |
| Oct | 3.5" | 4.9" | 0" | ✅ Rainfall sufficient |
| Nov | — | 2.5" | 0" | ❄️ Dormant |
| Dec | — | 3.7" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Castro County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Carrots 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.
Carrots Planting Timeline — Castro County, TX
Carrots Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Direct Sow | March 31 | Mar 31 – Apr 21 |
| Harvest | June 2 | Jun 2 – Jul 7 |
| Fall Sowing | August 15 | Aug 15 – Aug 29 |
Plant 0.5" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Direct Sow |
| April | Direct Sow |
| May | — |
| June | Harvest |
| July | Harvest |
| August | Fall Sowing |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.8"/week · Natural rainfall sufficient
📅 Days to Maturity
60–80 days
🧪 Soil pH
Needs 6–6.8 · Your soil: too_alkaline
🗺️ USDA Zone
Zone 7a
📆 Growing Season
193 days in Castro County
Growing Tips for Carrots in Castro County
Direct sow Carrots outdoors after April 14 in Castro County when soil has warmed and frost danger has passed.
Sandy soil in Castro County dries quickly — mulch Carrots with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.
Common pests for Carrots in this region include carrot rust fly and parsleyworm. Use row covers early in the season and inspect plants weekly.
General growing tips
Sow seeds directly in loose, stone-free soil for straight roots. Keep soil moist until germination which can take 2-3 weeks. Thin seedlings to 2 inches apart.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Isolate 1/2 mile from Queen Anne's Lace (wild carrot). Biennial — requires two seasons.
Carrots in Other Locations
Frequently Asked Questions
When should I plant Carrots in Castro County, TX?
Castro County is in Zone 7a with an average last frost of April 14. Plan your Carrots planting based on this frost date — see the calendar above for exact timing.
What planting zone is Castro County, TX?
Castro County, Texas is in USDA Hardiness Zone 7a. The average last spring frost is April 14 and first fall frost is October 24.
Your Castro County Garden Planner — Free
A 24-page printable planner built for Castro 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.