When to Plant Leeks in Ulster County, NY
This month in Ulster County, New York
A quick July briefing for Ulster County, New York gardeners — what's urgent, what's next, and what can wait.
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Harvest leeks as they ripen
Morning harvests are best — cooler temperatures mean crisper produce and longer fridge life.
Before August arrives, get these ready
- First harvests: leeks
- Fall sowing: leeks
Leeks are a mild, sweet allium that produces long white shanks. They are more refined than onions and are a key ingredient in soups, stews, and gratins.
Ulster County, New York is in USDA Zone 6a. The average last spring frost is April 24 and the first fall frost is October 23, giving you a growing season of approximately 182 days.
At an elevation of 1,121 feet, Ulster County receives approximately 39.3 inches of rainfall annually with predominantly silt loam soil. Summer highs average 89°F, providing good warmth for Leeks during the growing season.
Ulster County Soil Profile
Soil Type
Silt Loam
Soil pH
4.8-6.8
Drainage
Well Drained
Leeks 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 Ulster County
How your county's soil matches Leeks's growing requirements.
Soil pH
Your soil pH (4.8–6.8) is more acidic than Leeks prefers (6.0–7.0). Add garden lime to raise pH.
Soil Texture
The silt loam soil in Ulster County is excellent for Leeks — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (3.7%). Annual compost additions will help Leeks.
How to Plant Leeks
Fall planting: Sow 10 weeks before your first frost date for a fall harvest.
Leeks Water Budget
Monthly Watering Guide for Leeks
Leeks 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 | Leeks Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 2.4" | 0" | ❄️ Dormant |
| Feb | — | 2.4" | 0" | ❄️ Dormant |
| Mar | — | 3.2" | 0" | ❄️ Dormant |
| Apr | 3.5" | 2.9" | 0.6" | 💧 Light watering |
| May | 3.5" | 4" | 0" | ✅ Rainfall sufficient |
| Jun | 3.5" | 3.7" | 0" | ✅ Rainfall sufficient |
| Jul | 3.5" | 4.4" | 0" | ✅ Rainfall sufficient |
| Aug | 3.5" | 3.9" | 0" | ✅ Rainfall sufficient |
| Sep | 3.5" | 3.5" | 0" | ✅ Rainfall sufficient |
| Oct | 3.5" | 3.5" | 0" | ✅ Rainfall sufficient |
| Nov | — | 2.7" | 0" | ❄️ Dormant |
| Dec | — | 2.6" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Ulster County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Leeks 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.
Leeks Planting Timeline — Ulster County, NY
Leeks Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 20 | Mar 20 – Apr 3 |
| Transplant Outdoors | April 24 | Apr 24 – May 8 |
| Direct Sow | April 10 | Apr 10 – May 1 |
| Harvest | July 24 | Jul 24 – Oct 9 |
| Fall Sowing | August 14 | Aug 14 – Aug 28 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Start Indoors Transplant Outdoors Direct Sow |
| May | Transplant Outdoors Direct Sow |
| June | — |
| July | Harvest |
| August | Fall Sowing Harvest |
| September | Harvest |
| October | Harvest |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.8"/week · Natural rainfall sufficient
📅 Days to Maturity
90–150 days
🧪 Soil pH
Needs 6–7 · Your soil: too_acidic
🗺️ USDA Zone
Zone 6a
📆 Growing Season
182 days in Ulster County
Growing Tips for Leeks in Ulster County
Direct sow Leeks outdoors after April 24 in Ulster County when soil has warmed and frost danger has passed.
Common pests for Leeks in this region include onion maggots and thrips. Use row covers early in the season and inspect plants weekly.
General growing tips
Start seeds indoors 10-12 weeks before last frost. Transplant into trenches and hill soil around stems as they grow to increase the white portion. Harvest as needed.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Leeks in Other Locations
Frequently Asked Questions
When should I plant Leeks in Ulster County, NY?
Ulster County is in Zone 6a with an average last frost of April 24. Plan your Leeks planting based on this frost date — see the calendar above for exact timing.
What planting zone is Ulster County, NY?
Ulster County, New York is in USDA Hardiness Zone 6a. The average last spring frost is April 24 and first fall frost is October 23.
Your Ulster County Garden Planner — Free
A 22-page printable planner built for Ulster County (Zone 6a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.