When to Plant Hyssop in Sussex County, NJ
May in the garden — Sussex County, New Jersey
Your garden in Sussex County, New Jersey is working on a schedule, even when you're not. Here's where you should be this May.
June will be here before you know it — start on
- First harvests: hyssop
Hyssop is a semi-evergreen perennial herb with intense blue flower spikes that attract bees and butterflies. It has a minty, slightly bitter flavor used in liqueurs and teas.
Sussex County, New Jersey is in USDA Zone 6b. The average last spring frost is March 29 and the first fall frost is November 12, giving you a growing season of approximately 228 days.
At an elevation of 174 feet, Sussex County receives approximately 39 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86°F, providing good warmth for Hyssop during the growing season.
Sussex County Soil Profile
Soil Type
Silt Loam
Soil pH
4.8-6.4
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 Sussex County
How your county's soil matches Hyssop's growing requirements.
Soil pH
Your soil pH (4.8–6.4) is more acidic than Hyssop prefers (6.0–8.0). Add garden lime to raise pH.
Soil Texture
The silt loam soil in Sussex County is excellent for Hyssop — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (3.2%). Annual compost additions will help Hyssop.
How to Plant Hyssop
Succession Planting Hyssop
Sow every 8 weeks. Last sowing by Aug 14 to harvest before frost.
Plant Water Budget
Monthly Watering Guide for Hyssop
Hyssop needs approximately 0.5 inches of water per week (2.2" per month). Here's how your county's rainfall compares month by month.
| Month | Hyssop Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 2.6" | 0" | ❄️ Dormant |
| Feb | — | 2.4" | 0" | ❄️ Dormant |
| Mar | 2.2" | 3.1" | 0" | ✅ Rainfall sufficient |
| Apr | 2.2" | 3.1" | 0" | ✅ Rainfall sufficient |
| May | 2.2" | 3.2" | 0" | ✅ Rainfall sufficient |
| Jun | 2.2" | 3.4" | 0" | ✅ Rainfall sufficient |
| Jul | 2.2" | 3.9" | 0" | ✅ Rainfall sufficient |
| Aug | 2.2" | 3.8" | 0" | ✅ Rainfall sufficient |
| Sep | 2.2" | 3.1" | 0" | ✅ Rainfall sufficient |
| Oct | 2.2" | 3.4" | 0" | ✅ Rainfall sufficient |
| Nov | 2.2" | 3.5" | 0" | ✅ Rainfall sufficient |
| Dec | — | 3.4" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Mar–Nov in Sussex County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Hyssop 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.
Hyssop Planting Timeline — Sussex County, NJ
Hyssop Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | April 5 | Apr 5 – Apr 19 |
| Harvest | June 14 | Jun 14 – Aug 16 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Transplant Outdoors |
| May | — |
| June | Harvest |
| July | Harvest |
| August | Harvest |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.5"/week · Natural rainfall sufficient
📅 Days to Maturity
70–90 days
🧪 Soil pH
Needs 6–8 · Your soil: too_acidic
🗺️ USDA Zone
Zone 6b
📆 Growing Season
228 days in Sussex County
Growing Tips for Hyssop in Sussex County
Direct sow Hyssop outdoors after March 29 in Sussex County when soil has warmed and frost danger has passed.
General growing tips
Start seeds indoors or direct sow in spring. Prune back in early spring to encourage bushy growth. Hyssop is drought-tolerant once established and thrives in poor soil.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Hyssop in Other Locations
Frequently Asked Questions
When should I plant Hyssop in Sussex County, NJ?
Sussex County is in Zone 6b with an average last frost of March 29. Plan your Hyssop planting based on this frost date — see the calendar above for exact timing.
What planting zone is Sussex County, NJ?
Sussex County, New Jersey is in USDA Hardiness Zone 6b. The average last spring frost is March 29 and first fall frost is November 12.
Your Sussex County Garden Planner — Free
A 24-page printable planner built for Sussex County (Zone 6b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.