When to Plant Nasturtium in King County, TX
King County, Texas gardeners: here's your June plan
Your King County, Texas garden is entering a new phase. Here's what's on the schedule for June and why each task matters now.
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Harvest nasturtium as they ripen
Don't tug. Use scissors or pruners for clean cuts — torn stems invite disease.
Get ahead of 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.
King County, Texas is in USDA Zone 8a. The average last spring frost is March 31 and the first fall frost is November 7, giving you a growing season of approximately 221 days.
At an elevation of 3,170 feet, King County receives approximately 60.2 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 99°F, so Nasturtium may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring — great for early planting — but Nasturtium will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Nasturtium root diseases.
King County Soil Profile
Soil Type
Sandy Loam
Soil pH
7.8-8.4
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 King County
How your county's soil matches Nasturtium's growing requirements.
Soil pH
Your soil pH (7.8–8.4) is more alkaline than Nasturtium prefers (6.0–8.0). Add sulfur or peat moss to lower pH.
Soil Texture
Sandy soil in King County warms quickly in spring but drains fast. Nasturtium will need more frequent watering and regular compost additions to retain nutrients.
Organic Matter
Organic matter is low (1.1%). Add 2-3 inches of compost before planting Nasturtium.
How to Plant Nasturtium
Succession Planting Nasturtium
Sow every 6.3 weeks. Last sowing by Sep 03 to harvest before frost.
Nasturtium Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
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 | — | 4.7" | 0" | ❄️ Dormant |
| Feb | — | 3.2" | 0" | ❄️ Dormant |
| Mar | 2.2" | 3.9" | 0" | ✅ Rainfall sufficient |
| Apr | 2.2" | 2.3" | 0" | ✅ Rainfall sufficient |
| May | 2.2" | 1.5" | 0.7" | 💧 Light watering |
| Jun | 2.2" | 2.2" | 0" | ✅ Rainfall sufficient |
| Jul | 2.2" | 10.4" | 0" | ✅ Rainfall sufficient |
| Aug | 2.2" | 11.5" | 0" | ✅ Rainfall sufficient |
| Sep | 2.2" | 8.1" | 0" | ✅ Rainfall sufficient |
| Oct | 2.2" | 5.7" | 0" | ✅ Rainfall sufficient |
| Nov | 2.2" | 3" | 0" | ✅ Rainfall sufficient |
| Dec | — | 3.7" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Mar–Nov in King County). 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 — King County, TX
Nasturtium Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 3 | Mar 3 – Mar 17 |
| Transplant Outdoors | March 24 | Mar 24 – Apr 7 |
| Direct Sow | March 24 | Mar 24 – Apr 14 |
| Bloom | May 19 | May 19 – Oct 20 |
Plant 0.5" deep · 10" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors Transplant Outdoors Direct Sow |
| April | Transplant Outdoors Direct Sow |
| May | Bloom |
| June | Bloom |
| July | Bloom |
| August | Bloom |
| September | Bloom |
| October | Bloom |
| November | — |
| 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_alkaline
🗺️ USDA Zone
Zone 8a
📆 Growing Season
221 days in King County
Growing Tips for Nasturtium in King County
Direct sow Nasturtium outdoors after March 31 in King County when soil has warmed and frost danger has passed.
Sandy soil in King County dries quickly — mulch Nasturtium with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.
With summer highs reaching 99°F in King County, provide afternoon shade for Nasturtium and water deeply in the morning.
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 King County, TX?
King County is in Zone 8a with an average last frost of March 31. Plan your Nasturtium planting based on this frost date — see the calendar above for exact timing.
What planting zone is King County, TX?
King County, Texas is in USDA Hardiness Zone 8a. The average last spring frost is March 31 and first fall frost is November 7.
Your King County Garden Planner — Free
A 22-page printable planner built for King County (Zone 8a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.