When to plant Broccoli in Valley County, ID
Broccoli planted in Valley County between June 4 and June 25 matures in 60–90 days — well before the September 3 first frost. A second sowing from June 25 to July 9 extends the harvest into fall.
When to Plant Broccoli in Valley County, ID
Top priorities for Valley County, Idaho gardeners in June
We've pulled the most time-sensitive tasks for Valley County, Idaho this June and put them front and centre. Tackle them in order.
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Plant out broccoli
Pick a cloudy afternoon or evening to plant. Less transplant shock, and your seedlings will barely blink.
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Seed broccoli outdoors
Succession planting is the secret here. Put in a row now, another in 2 weeks, a third in 4.
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Sow broccoli for an autumn harvest
Count back from your first frost (September 3) — these need to mature before the cold arrives.
Before July arrives, get these ready
- Starting indoors: broccoli
Broccoli is a nutrient-dense cool-season crop that produces large central heads followed by smaller side shoots. It is one of the most popular garden vegetables.
Valley County, Idaho is in USDA Zone 5a. The average last spring frost is June 18 and the first fall frost is September 3, giving you a growing season of approximately 77 days.
At an elevation of 7,884 feet, Valley County receives approximately 17.8 inches of rainfall annually with predominantly loam soil. Summer highs average 83°F, so choose short-season varieties of Broccoli to ensure they mature before fall. With low rainfall, drip irrigation is essential for growing Broccoli successfully. Mulch heavily to conserve soil moisture.
Valley County Soil Profile
Soil Type
Loam
Soil pH
6.4-8.4
Drainage
Well Drained
Broccoli 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 Valley County
How your county's soil matches Broccoli's growing requirements.
Soil pH
Your soil pH (6.4–8.4) is more alkaline than Broccoli prefers (6.0–7.0). Add sulfur or peat moss to lower pH.
Soil Texture
The loam soil in Valley County is excellent for Broccoli — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.6%). Annual compost additions will help Broccoli.
How to Plant Broccoli
Fall planting: Sow 10 weeks before your first frost date for a fall harvest.
How Much Broccoli to Grow
For a family of 4, plant approximately 12 broccoli plants in about 30 sq ft. In Valley County's 77-day season, you'll have plenty of time for a full harvest. Plan your garden layout →
Broccoli Water Budget
Water stress score is 8/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Broccoli
Broccoli needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Broccoli Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.2" | 0" | ❄️ Dormant |
| Feb | — | 1" | 0" | ❄️ Dormant |
| Mar | — | 1.7" | 0" | ❄️ Dormant |
| Apr | — | 2.2" | 0" | ❄️ Dormant |
| May | — | 2.1" | 0" | ❄️ Dormant |
| Jun | 4.3" | 1.1" | 3.2" | 🚿 Regular watering |
| Jul | 4.3" | 1.5" | 2.8" | 🚿 Regular watering |
| Aug | 4.3" | 1.9" | 2.4" | 🚿 Regular watering |
| Sep | 4.3" | 1.4" | 2.9" | 🚿 Regular watering |
| Oct | — | 1.5" | 0" | ❄️ Dormant |
| Nov | — | 1.4" | 0" | ❄️ Dormant |
| Dec | — | 0.9" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Jun–Sep in Valley County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Broccoli 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.
Broccoli Planting Timeline — Valley County, ID
Broccoli Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | May 14 | May 14 – May 28 |
| Transplant Outdoors | June 18 | Jun 18 – Jul 2 |
| Direct Sow | June 4 | Jun 4 – Jun 25 |
| Harvest | August 20 | Aug 20 – Oct 1 |
| Fall Sowing | June 25 | Jun 25 – Jul 9 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | — |
| May | Start Indoors |
| June | Transplant Outdoors Direct Sow Fall Sowing |
| July | Transplant Outdoors Fall Sowing |
| August | Harvest |
| September | Harvest |
| October | Harvest |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1"/week · Only during dry spells
📅 Days to Maturity
60–90 days
🧪 Soil pH
Needs 6–7 · Your soil: too_alkaline
🗺️ USDA Zone
Zone 5a
📆 Growing Season
77 days in Valley County
Growing Tips for Broccoli in Valley County
Direct sow Broccoli outdoors after June 18 in Valley County when soil has warmed and frost danger has passed.
Your 77.0-day growing season in Valley County is tight for Broccoli (60.0-90.0 days to maturity). Start indoors and choose early-maturing varieties.
Common pests for Broccoli in this region include cabbage worm and flea beetles. Use row covers early in the season and inspect plants weekly.
Valley County receives only 18" of rain annually. Broccoli needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.
General growing tips
Start seeds indoors 6-8 weeks before last frost. Provide consistent moisture to prevent hollow stems. Harvest heads before yellow flowers appear.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Isolate 1/2 mile from other brassicas. Biennial — must overwinter roots.
Broccoli in Other Locations
Frequently Asked Questions
When should I plant Broccoli in Valley County, ID?
Valley County is in Zone 5a with an average last frost of June 18. Plan your Broccoli planting based on this frost date — see the calendar above for exact timing.
What planting zone is Valley County, ID?
Valley County, Idaho is in USDA Hardiness Zone 5a. The average last spring frost is June 18 and first fall frost is September 3.
When should I plant Broccoli in Valley County, ID?
In Valley County, ID, plant Broccoli after the last frost (around June 18) and before the first frost (around September 3). Best results when soil holds above 50°F.
What growing zone is Valley County, ID for Broccoli?
Valley County sits in USDA Zone 5a. Broccoli grows reliably in zones 2a through 11b, so it's a good fit here.
Can Broccoli grow in Valley County's climate?
Yes — Broccoli grows well in Valley County's temperate climate. Valley County averages a 77-day frost-free season, with last frost around June 18 and first frost around September 3.
Your Valley County Garden Planner — Free
A 22-page printable planner built for Valley County (Zone 5a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.