When to Plant Sweet Alyssum in Washington County, NE
Your June planting checklist for Washington County, Nebraska
Here's what deserves your attention in Washington County, Nebraska this month. Everything below is tailored to Zone 5b and timed around your local frost dates.
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Sow sweet alyssum in trays indoors
Your window is short. These crops want several weeks of indoor growth before they go outside.
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It's harvest week for sweet alyssum
Taste as you pick. The first ripe produce is the best feedback loop you'll get all season.
Get ahead of July
- First harvests: sweet alyssum
Sweet Alyssum (Lobularia maritima) is a low-growing cool-season annual prized for its honey-scented clusters of tiny white, pink, or purple flowers. A workhorse border plant, it tolerates light frost, self-seeds readily, and attracts beneficial insects throughout its bloom season. In warm climates it often re-blooms in fall after summer heat fades.
Washington County, Nebraska is in USDA Zone 5b. The average last spring frost is April 23 and the first fall frost is October 11, giving you a growing season of approximately 171 days.
At an elevation of 508 feet, Washington County receives approximately 29.5 inches of rainfall annually with predominantly loam soil. Summer highs average 85°F, providing good warmth for Sweet Alyssum during the growing season.
Washington County Soil Profile
Soil Type
Loam
Soil pH
6.8-7.6
Drainage
Well Drained
Sweet Alyssum 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 Washington County
How your county's soil matches Sweet Alyssum's growing requirements.
Soil pH
Your soil pH (6.8–7.6) overlaps with Sweet Alyssum's range (6.0–7.5), though not a perfect match.
Soil Texture
The loam soil in Washington County is excellent for Sweet Alyssum — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Sweet Alyssum.
Organic Matter
Organic matter is excellent (4.2%) — Sweet Alyssum will thrive.
How to Plant Sweet Alyssum
Succession Planting Sweet Alyssum
Sow every 5.1 weeks. Last sowing by Aug 12 to harvest before frost.
Sweet Alyssum Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Sweet Alyssum
Sweet Alyssum 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 | Sweet Alyssum Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 0.9" | 0" | ❄️ Dormant |
| Feb | — | 1.2" | 0" | ❄️ Dormant |
| Mar | — | 1.9" | 0" | ❄️ Dormant |
| Apr | 2.2" | 2.8" | 0" | ✅ Rainfall sufficient |
| May | 2.2" | 4.4" | 0" | ✅ Rainfall sufficient |
| Jun | 2.2" | 5" | 0" | ✅ Rainfall sufficient |
| Jul | 2.2" | 3.8" | 0" | ✅ Rainfall sufficient |
| Aug | 2.2" | 3.3" | 0" | ✅ Rainfall sufficient |
| Sep | 2.2" | 2.5" | 0" | ✅ Rainfall sufficient |
| Oct | 2.2" | 1.8" | 0.4" | 💧 Light watering |
| Nov | — | 1.2" | 0" | ❄️ Dormant |
| Dec | — | 0.7" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Washington County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Sweet Alyssum 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.
Sweet Alyssum Planting Timeline — Washington County, NE
Sweet Alyssum Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 5 | Mar 5 – Mar 19 |
| Transplant Outdoors | April 23 | Apr 23 – May 7 |
| Direct Sow | April 9 | Apr 9 – Apr 30 |
| Bloom | June 4 | Jun 4 – Aug 13 |
· 6" apart · Rows 8" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Transplant Outdoors Direct Sow |
| May | Transplant Outdoors |
| June | Bloom |
| July | Bloom |
| August | Bloom |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.5"/week · Natural rainfall sufficient
📅 Days to Maturity
45–60 days
🧪 Soil pH
Needs 6–7.5 · Your soil: acceptable
🗺️ USDA Zone
Zone 5b
📆 Growing Season
171 days in Washington County
Growing Tips for Sweet Alyssum in Washington County
Direct sow Sweet Alyssum outdoors after April 23 in Washington County when soil has warmed and frost danger has passed.
Your generous 171.0-day season in Washington County allows multiple plantings of Sweet Alyssum. Sow every 22.0 days for continuous harvest.
Common pests for Sweet Alyssum in this region include cabbage worm and flea beetles. Use row covers early in the season and inspect plants weekly.
General growing tips
Surface-sow seeds — they need light to germinate. Direct-sow as soon as soil can be worked in spring; in zones 7+ also sow in fall. Thin to 6 inches apart. Shear back hard in midsummer when heat causes dormancy — plants recover and re-bloom when cool weather returns. Self-seeds prolifically; allow a few plants to set seed for a perpetual colony.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Sweet Alyssum in Other Locations
Frequently Asked Questions
When should I plant Sweet Alyssum in Washington County, NE?
Washington County is in Zone 5b with an average last frost of April 23. Plan your Sweet Alyssum planting based on this frost date — see the calendar above for exact timing.
What planting zone is Washington County, NE?
Washington County, Nebraska is in USDA Hardiness Zone 5b. The average last spring frost is April 23 and first fall frost is October 11.
Your Washington County Garden Planner — Free
A 22-page printable planner built for Washington County (Zone 5b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.