When to Plant Cauliflower in Lehigh County, PA
Lehigh County, Pennsylvania gardeners: here's your May plan
Your Lehigh County, Pennsylvania garden is entering a new phase. Here's what's on the schedule for May and why each task matters now.
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Start cauliflower under lights
These need a head start before your last frost (April 20). Sow into cells now so you're ready to transplant in a few weeks.
Get ahead of June
- First harvests: cauliflower
Cauliflower is a cool-season brassica that produces dense white, purple, or green heads called curds. It is more finicky than broccoli but rewards with a mild, nutty flavor.
Lehigh County, Pennsylvania is in USDA Zone 7a. The average last spring frost is April 20 and the first fall frost is October 24, giving you a growing season of approximately 187 days.
At an elevation of 376 feet, Lehigh County receives approximately 44.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 89°F, providing good warmth for Cauliflower during the growing season.
Lehigh County Soil Profile
Soil Type
Silt Loam
Soil pH
5.2-6.2
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 Lehigh County
How your county's soil matches Cauliflower's growing requirements.
Soil pH
Your soil pH (5.2–6.2) is more acidic than Cauliflower prefers (6.0–7.0). Add garden lime to raise pH.
Soil Texture
The silt loam soil in Lehigh County is excellent for Cauliflower — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Cauliflower.
Organic Matter
Organic matter is moderate (4.0%). Annual compost additions will help Cauliflower.
How to Plant Cauliflower
Fall planting: Sow 10 weeks before your first frost date for a fall harvest.
Succession Planting Cauliflower
Sow every 6.3 weeks. Last sowing by Jul 16 to harvest before frost.
For a dedicated fall crop, sow by Aug 15.
Plant Water Budget
Monthly Watering Guide for Cauliflower
Cauliflower needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Cauliflower Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 3.6" | 0" | ❄️ Dormant |
| Feb | — | 3.2" | 0" | ❄️ Dormant |
| Mar | — | 4.2" | 0" | ❄️ Dormant |
| Apr | 4.3" | 4.3" | 0" | ✅ Rainfall sufficient |
| May | 4.3" | 3.7" | 0.6" | 💧 Light watering |
| Jun | 4.3" | 4.2" | 0.1" | 💧 Light watering |
| Jul | 4.3" | 4.7" | 0" | ✅ Rainfall sufficient |
| Aug | 4.3" | 3.8" | 0.5" | 💧 Light watering |
| Sep | 4.3" | 3.6" | 0.7" | 💧 Light watering |
| Oct | 4.3" | 3.4" | 0.9" | 💧 Light watering |
| Nov | — | 3.1" | 0" | ❄️ Dormant |
| Dec | — | 3.1" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Lehigh County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Cauliflower 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.
Cauliflower Planting Timeline — Lehigh County, PA
Cauliflower Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 16 | Mar 16 – Mar 30 |
| Transplant Outdoors | April 20 | Apr 20 – May 4 |
| Direct Sow | April 6 | Apr 6 – Apr 27 |
| Harvest | June 15 | Jun 15 – Aug 17 |
| Fall Sowing | August 15 | Aug 15 – Aug 29 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Transplant Outdoors Direct Sow |
| May | Transplant Outdoors |
| June | Harvest |
| July | Harvest |
| August | Fall Sowing Harvest |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1"/week · Natural rainfall sufficient
📅 Days to Maturity
55–100 days
🧪 Soil pH
Needs 6–7 · Your soil: too_acidic
🗺️ USDA Zone
Zone 7a
📆 Growing Season
187 days in Lehigh County
Growing Tips for Cauliflower in Lehigh County
Direct sow Cauliflower outdoors after April 20 in Lehigh County when soil has warmed and frost danger has passed.
Common pests for Cauliflower 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 6 weeks before transplanting. Blanch white varieties by tying outer leaves over the head. Provide consistent moisture and avoid temperature extremes.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Cauliflower in Other Locations
Frequently Asked Questions
When should I plant Cauliflower in Lehigh County, PA?
Lehigh County is in Zone 7a with an average last frost of April 20. Plan your Cauliflower planting based on this frost date — see the calendar above for exact timing.
What planting zone is Lehigh County, PA?
Lehigh County, Pennsylvania is in USDA Hardiness Zone 7a. The average last spring frost is April 20 and first fall frost is October 24.
Your Lehigh County Garden Planner — Free
A 24-page printable planner built for Lehigh 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.