When to plant Nasturtium in Ketchikan Gateway Borough County,
For Ketchikan Gateway Borough County, gardeners: plant Nasturtium April 25 through May 16 once soil reads 50°F.
When to Plant Nasturtium in Ketchikan Gateway Borough, AK
Your June gardening checklist
We've pulled the most time-sensitive tasks for Ketchikan Gateway Borough, Alaska this June and put them front and centre. Tackle them in order.
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Start harvesting nasturtium
If you can't use it all right away, check the food-preservation section of your planner.
A few tasks this June that'll pay off in July
- First harvests: nasturtium
Nasturtium (Tropaeolum majus) is a fast-growing annual with distinctive round, lily-pad leaves and bold trumpet-shaped blooms in warm oranges, reds, and yellows. Both the flowers and leaves are edible with a peppery watercress flavor. Planted near vegetables, nasturtiums act as a sacrifice trap-crop, luring aphids away from more valuable plants. They thrive in poor, dry soil — rich conditions produce lush foliage but few flowers.
Ketchikan Gateway Borough, Alaska is in USDA Zone 7b. The average last spring frost is April 25 and the first fall frost is October 19, giving you a growing season of approximately 177 days.
At an elevation of 1,212 feet, Ketchikan Gateway Borough receives approximately 57.5 inches of rainfall annually with predominantly silt loam soil. Summer highs average 65°F, so choose short-season varieties of Nasturtium to ensure they mature before fall. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Nasturtium root diseases.
Ketchikan Gateway Borough Soil Profile
Soil Type
Silt Loam
Soil pH
5-6.7
Drainage
Well Drained
Nasturtium 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 Ketchikan Gateway Borough
How your county's soil matches Nasturtium's growing requirements.
Soil pH
Your soil pH (5.0–6.7) is more acidic than Nasturtium prefers (6.0–8.0). Add garden lime to raise pH.
Soil Texture
The silt loam soil in Ketchikan Gateway Borough is excellent for Nasturtium — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Nasturtium prefers dry conditions but your soil drains poorly. Use raised beds or mounded rows to prevent root rot.
Organic Matter
Organic matter is excellent (5.9%) — Nasturtium will thrive.
How to Plant Nasturtium
Succession Planting Nasturtium
Sow every 6.3 weeks. Last sowing by Aug 15 to harvest before frost.
Nasturtium Water Budget
Monthly Watering Guide for Nasturtium
Nasturtium 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 | Nasturtium Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 2.8" | 0" | ❄️ Dormant |
| Feb | — | 2.6" | 0" | ❄️ Dormant |
| Mar | — | 1.8" | 0" | ❄️ Dormant |
| Apr | 2.2" | 2" | 0.2" | 💧 Light watering |
| May | 2.2" | 2.4" | 0" | ✅ Rainfall sufficient |
| Jun | 2.2" | 4.5" | 0" | ✅ Rainfall sufficient |
| Jul | 2.2" | 6.6" | 0" | ✅ Rainfall sufficient |
| Aug | 2.2" | 9.5" | 0" | ✅ Rainfall sufficient |
| Sep | 2.2" | 11" | 0" | ✅ Rainfall sufficient |
| Oct | 2.2" | 6.6" | 0" | ✅ Rainfall sufficient |
| Nov | — | 3.8" | 0" | ❄️ Dormant |
| Dec | — | 3.9" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Ketchikan Gateway Borough). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Nasturtium 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.
Nasturtium Planting Timeline — Ketchikan Gateway Borough, AK
Nasturtium Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 28 | Mar 28 – Apr 11 |
| Transplant Outdoors | April 25 | Apr 25 – May 9 |
| Direct Sow | April 25 | Apr 25 – May 16 |
| Bloom | June 20 | Jun 20 – Nov 7 |
Plant 0.5" deep · 10" apart · Rows 12" 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 | Bloom |
| July | Bloom |
| August | Bloom |
| September | Bloom |
| October | Bloom |
| November | Bloom |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.5"/week · Natural rainfall sufficient
📅 Days to Maturity
55–65 days
🧪 Soil pH
Needs 6–8 · Your soil: too_acidic
🗺️ USDA Zone
Zone 7b
📆 Growing Season
177 days in Ketchikan Gateway Borough
Growing Tips for Nasturtium in Ketchikan Gateway Borough
Direct sow Nasturtium outdoors after April 25 in Ketchikan Gateway Borough when soil has warmed and frost danger has passed.
General growing tips
Direct-sow large seeds 1/2 inch deep after last frost; soak seeds overnight to speed germination (7-10 days). Nasturtiums dislike root disturbance so direct sowing is strongly preferred. Avoid fertilizing — poor soil brings the best bloom. Trailing types can cover banks and climb trellises; dwarf types suit containers. In hot climates (zones 9+) plant in fall for winter/spring bloom as plants struggle in peak summer heat.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Nasturtium in Other Locations
Frequently Asked Questions
When should I plant Nasturtium in Ketchikan Gateway Borough, AK?
Ketchikan Gateway Borough is in Zone 7b with an average last frost of April 25. Plan your Nasturtium planting based on this frost date — see the calendar above for exact timing.
What planting zone is Ketchikan Gateway Borough, AK?
Ketchikan Gateway Borough, Alaska is in USDA Hardiness Zone 7b. The average last spring frost is April 25 and first fall frost is October 19.
When should I plant Nasturtium in Ketchikan Gateway Borough County, ?
In Ketchikan Gateway Borough County, , plant Nasturtium after the last frost (around April 25) and before the first frost (around October 19). Best results when soil holds above 50°F.
What growing zone is Ketchikan Gateway Borough County, for Nasturtium?
Ketchikan Gateway Borough County sits in USDA Zone 7b. Nasturtium grows reliably in zones 2a through 11b, so it's a good fit here.
Can Nasturtium grow in Ketchikan Gateway Borough County's climate?
Yes — Nasturtium grows well in Ketchikan Gateway Borough County's temperate climate. Ketchikan Gateway Borough County averages a 177-day frost-free season, with last frost around April 25 and first frost around October 19.
Your Ketchikan Gateway Borough Garden Planner — Free
A 22-page printable planner built for Ketchikan Gateway Borough (Zone 7b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.