Bonner County, ID — Planting Guide
Bonner County is in USDA Zone 5b. The average last spring frost is May 5 and the first fall frost is October 3, giving you a growing season of approximately 151 days.
At an elevation of 7,480 ft, Bonner County receives approximately 12.9 in of rainfall annually. Summer highs average 86°F with winter lows around 13°F. The predominant soil type is Loam.
Based on 31 years of NOAA climate station data, the last frost date here varies by 46 days year to year — ranging from April 15 in warm years to June 1 in cold years. The growing season is trending longer by about 1.77 days per decade. Bonner County scores 29/100 (Challenging) on the Microclimate Index.
🌡️ Zone
5b (-15°F to -10°F min)
❄️ Last Frost
May 5
🍂 First Frost
October 3
📅 Growing Season
151 days
⛰️ Elevation
7,480 ft
🌧️ Annual Rainfall
12.9 in
Monthly Watering Calendar
When you'll need to water your garden — based on average monthly rainfall vs. the ~1 inch/week most gardens need.
View detailed monthly data
| Month | Avg Rainfall | Rainy Days | Extra Water Needed | Watering Effort |
|---|---|---|---|---|
| Jan | 0.9 in | 7 days | — | None |
| Feb | 0.7 in | 5 days | — | None |
| Mar | 1.1 in | 7 days | — | None |
| Apr | 1.5 in | 9 days | 2.8 in | High |
| May | 1.5 in | 7 days | 2.8 in | High |
| Jun | 0.9 in | 5 days | 3.4 in | Critical |
| Jul | 1.1 in | 6 days | 3.2 in | Critical |
| Aug | 1.2 in | 6 days | 3.1 in | Critical |
| Sep | 1.1 in | 6 days | 3.2 in | Critical |
| Oct | 1.1 in | 5 days | 3.2 in | Critical |
| Nov | 0.9 in | 5 days | — | None |
| Dec | 0.7 in | 5 days | — | None |
Annual total: 12.7 in. Water needs vary by crop — tomatoes need ~1.2"/week while herbs like rosemary need only 0.3"/week. Check individual plant pages for crop-specific water budgets that factor in your county's rainfall and soil drainage.
Bonner County Soil Profile
Soil Type
Loam
Soil pH
6.4-8.2
Drainage
Well Drained
Frost Risk Probability
Based on 31 years of NOAA weather station data from 3 stations
Beginners: Plant frost-sensitive crops (tomatoes, peppers, squash) after the "Safe" date on the left. Harvest or cover them before the "Protect by" date on the right. Hardy crops (lettuce, peas, kale) can go in the yellow transition zones.
How to read this table: "Conservative" means you're safe from frost 9 out of 10 years — best for beginners and frost-sensitive crops. "Average year" is the typical date. "Aggressive" means only 1 in 10 years is that warm — experienced gardeners with frost protection can try these dates.
| Planting Strategy | Last Spring Frost | First Fall Frost | Frost-Free Days |
|---|---|---|---|
| Conservative (safest) | Jun 1 | Oct 25 | 146 days |
| Cautious | May 14 | Oct 11 | 150 days |
| Average year | May 5 | Oct 3 | 151 days |
| Optimistic | Apr 28 | Sep 20 | 145 days |
| Aggressive (risky) | Apr 15 | Sep 3 | 141 days |
Not very — frost dates can vary by ±46 days year-to-year. Use the "Conservative" row in the table below, and keep row covers handy for surprise late frosts.
Yes — growing seasons are getting longer here (about 1.8 days per decade). Spring is arriving earlier than it used to. Good news for gardeners.
Gardening Difficulty Score
Bonner County has challenging growing conditions. Season extension and careful variety selection are essential.
Local Gardening Help in Bonner County
Free expert help is closer than you think. Your county's cooperative extension office connects you with trained gardeners, soil testing labs, and local programs — all specific to Bonner County's climate and soil.
County Extension Office
Bonner County University of Idaho Extension Extension Office
Phone: 208-885-6681
Visit Extension Office Website →
Extension offices are run by land-grant universities and funded by the USDA. Their advice is free, research-based, and tailored to your county's specific conditions.
Master Gardener Program
Free gardening help from trained volunteers
Master Gardeners are community volunteers who complete 40–60 hours of university horticultural training. They answer gardening questions, diagnose plant problems, and offer workshops — all free.
Many extension offices run a Master Gardener hotline where you can call or email with photos of plant problems for free diagnosis.
Soil Testing
Available through your extension office
Before amending your soil, get it tested. Your extension office offers soil testing (typically $10–$25) that tells you exact pH, nutrient levels, and amendment recommendations specific to what you want to grow.
Services Available in Bonner County
Finding local nurseries & garden centers in Bonner County
Why Buy Local
Local nurseries carry plants that are proven to grow in your area. Staff can give you advice specific to Bonner County's soil and climate that big-box stores can't. Plants from local growers are typically hardier because they're already acclimated to your zone.
How to Find Them
Search for "nurseries near Bonner County ID" or "garden center Bonner County" on Google Maps. Also check with your extension office — they often maintain lists of reputable local nurseries and plant sales.
Community gardens & gardening groups
Community gardens are a great way to learn from experienced gardeners in your area, especially if you're limited on space. Search "community garden Bonner County ID" or check your extension office and local parks department. Facebook groups like "Bonner County Gardeners" or "Idaho Gardening" are also excellent for local advice and plant swaps.
What to Plant After Your Harvest
After your first crops finish, use the remaining frost-free days to grow a second round.
Show 6 more succession options
Sunlight & Day Length
Monthly daylight hours and peak sun — critical for onion varieties, photoperiod-sensitive plants, and solar garden planning.
Longest Day
15.8 hours
Summer solstice daylight
Shortest Day
8.2 hours
Winter solstice daylight
Peak Sun Hours
11.2 hr/day peak (summer)
Peak sun hours (green dashed line below) account for cloud cover — this is the usable direct sunlight your garden actually receives. Most vegetables need 6+ peak sun hours.
Onion tip: Your long summer days (14+ hours) support long-day onion varieties like Walla Walla, Sweet Spanish, and Ailsa Craig.
View detailed monthly data
| Month | Daylight Hours | Peak Sun Hours | Day Length |
|---|---|---|---|
| January | 8.6 hr | 4.7 hr | Short day |
| February | 10 hr | 5.9 hr | Short day |
| March | 11.6 hr | 6.9 hr | Short day |
| April | 13.4 hr | 7.7 hr | Neutral |
| May | 15 hr | 9.2 hr | Long day |
| June | 15.8 hr | 11.2 hr | Long day |
| July | 15.5 hr | 11.2 hr | Long day |
| August | 14.1 hr | 10 hr | Long day |
| September | 12.3 hr | 8.4 hr | Neutral |
| October | 10.5 hr | 6.6 hr | Short day |
| November | 9 hr | 5.2 hr | Short day |
| December | 8.2 hr | 4.7 hr | Short day |
Peak sun hours factor in typical cloud cover — use these for solar panel and shade-planning calculations.
Soil Temperature & Composting Calendar
Monthly soil temps tell you when to plant warm-season crops, and when your compost pile is actively working.
Plant Warm Crops When
Soil reaches 60°F+
Soil rarely reaches 60°F — use black plastic mulch to warm soil.
Best Month to Compost
Jul
Microbial activity peaks when soil is warm.
Active Composting
2 months
Short season — insulate pile or use indoor vermicomposting.
View detailed monthly data
| Month | Soil 4" Deep | Soil 8" Deep | Compost Activity | Time to Finish |
|---|---|---|---|---|
| Jan | -1°F | 8°F | ❄️ Dormant | ~36 weeks |
| Feb | -1°F | 6°F | ❄️ Dormant | ~36 weeks |
| Mar | 8°F | 11°F | ❄️ Dormant | ~36 weeks |
| Apr | 23°F | 22°F | ❄️ Dormant | ~36 weeks |
| May | 34°F | 30°F | ❄️ Dormant | ~36 weeks |
| Jun | 45°F | 42°F | 🐢 Slow | ~24 weeks |
| Jul | 52°F | 48°F | ♻️ Active | ~14 weeks |
| Aug | 53°F | 49°F | ♻️ Active | ~14 weeks |
| Sep | 48°F | 47°F | 🐢 Slow | ~24 weeks |
| Oct | 33°F | 35°F | ❄️ Dormant | ~36 weeks |
| Nov | 19°F | 25°F | ❄️ Dormant | ~36 weeks |
| Dec | 6°F | 13°F | ❄️ Dormant | ~36 weeks |
Highlighted rows = soil 60°F+ (safe for warm-season transplants). Compost finishes fastest during peak activity months.
Pest & Disease Pressure in Bonner County
Computed from local climate patterns — warmer, humid conditions increase pest generations and fungal disease risk.
Insect Pest Pressure
Moderate — common pests appear but manageable with monitoring.
Disease Risk
Low disease risk — dry conditions reduce fungal problems.
Seasonal Risk
View 6 common pests in your area
| Pest | Risk Level | Peak Months |
|---|---|---|
| Aphids | Moderate | May, Jun, Jul, Aug |
| Japanese beetles | Moderate | Jun, Jul, Aug |
| Squash bugs | Low | Jun, Jul, Aug |
| Tomato hornworms | Low | Jul, Aug |
| Cabbage loopers | Moderate | May, Jun, Jul, Aug |
| Slugs | Low | Apr, May, Jun |
Organic pest management tips
- Maintain healthy soil with regular compost additions to build natural pest resistance
- Practice crop rotation annually to break pest cycles
- Encourage beneficial insects with flowering herbs like dill, fennel, and yarrow
Cover Crops for Bonner County
Cover crops protect bare soil, fix nitrogen, suppress weeds, and improve soil structure — with county-specific planting dates.
Spring Cover Crops (3 options) — Build soil before the main growing season
| Crop | Plant By | Terminate | N-Fixing | Soil Benefit |
|---|---|---|---|---|
| Buckwheat | May 13 | Aug 8 | — | Rapid growth, attracts pollinators, suppresses weeds |
| Sorghum-sudan grass | May 12 | Aug 1 | — | Massive biomass, breaks compaction, suppresses nematodes |
| White clover | Apr 4 | Aug 8 | ✓ Yes | Living mulch, fixes nitrogen, permanent ground cover |
Summer Cover Crops (1 options) — Fill gaps and suppress weeds between plantings
| Crop | Plant By | Terminate | N-Fixing | Soil Benefit |
|---|---|---|---|---|
| Sunflowers | May 21 | Sep 12 | — | Deep roots break compaction, attract pollinators and beneficial insects |
Fall Cover Crops (6 options) — Plant after harvest to protect soil over winter
| Crop | Plant By | Terminate | N-Fixing | Soil Benefit |
|---|---|---|---|---|
| Austrian winter peas | Aug 7 | Apr 21 | ✓ Yes | Fixes nitrogen, good for heavy clay soils |
| Daikon radish | Aug 16 | Apr 21 | — | Deep taproot breaks compaction, excellent for clay soils |
| Hairy vetch | Jul 17 | Apr 14 | ✓ Yes | Excellent nitrogen fixer, good for depleted soils |
| Oats | Sep 1 | Apr 14 | — | Quick biomass, winterkills in cold zones — no spring tillage needed |
| Winter rye | Jun 27 | Apr 14 | — | Suppresses weeds, prevents erosion, breaks up compacted soil |
| Winter wheat | Jul 7 | Apr 21 | — | Erosion control, weed suppression, good biomass |
Wind & Microclimate
Wind dries soil, stresses plants, and affects frost patterns. Understanding your exposure helps with garden placement.
Seasonal Wind Speed
Spring: 15 mph Summer: 11 mph
Fall: 12 mph Winter: 15 mph
Prevailing wind: W. Windy area — plant a windbreak hedge on the W side of your garden.
Windbreak Benefit
6.9/10
Moderately beneficial — a simple fence or trellis can protect delicate crops from wind stress.
Frost Pocket Risk
High
Hilly terrain with 1,440 ft of elevation range — cold air pools in low spots. Avoid planting frost-sensitive crops in valleys.
Rainwater Harvesting Potential
How much water you can collect, when to collect it, and what size system you need for your garden.
Annual Collection
6,329 gal
Per 1,000 sq ft of roof area (at 80% collection efficiency)
Recommended Setup
8 rain barrels (55 gal each)
For a typical 500 sq ft garden. Serious collectors: consider a 2,000 gal tank.
Legal Status
Unrestricted
Rainwater harvesting is fully legal in your state with no restrictions.
Best Collection Months
Mar, Apr, May, Aug
Highest rainfall months — your barrels will fill up quickly during these months.
Months to Draw From Storage
Jan, Feb, Jun, Nov, Dec
Dry months when you'll rely on stored water — size your storage for this gap.
Rainwater collection tips for your area
- Your county receives approximately 12.7 inches of rain per year
- A 1,000 sq ft roof can collect roughly 6,329 gallons annually
- Rainwater harvesting is fully legal in your state
- In your dry climate, every drop counts — consider a larger cistern system
- Position collection tanks in shade to reduce evaporation and algae growth
Soil & Growing Conditions in Bonner County
Soil Type
Loam
Soil pH 6.4–8.2 · Moderately Well Drained drainage
Native soil is well-suited to most vegetables and herbs with regular compost additions.
Watering Needs
Drought stress: 7.5/10
High drought stress. Consistent irrigation is essential — consider drip systems, heavy mulch, and drought-tolerant varieties.
Season Tips
151-day frost-free season
Start warm-season crops indoors and focus on short-season varieties. Cold frames extend your season by 3–4 weeks in fall.
Free Garden Planner
Plan your entire garden season — organize planting dates, track what you're growing, and know exactly when to start seeds, transplant, and harvest.
Recommended for Your Garden
Test your soil pH, nitrogen, phosphorus, and potassium levels before planting.
Get instant, accurate soil pH readings to fine-tune your amendments.
Boost soil fertility and structure with rich, well-aged organic compost.
🥬 Vegetables to Grow in Bonner County
106 vegetables that grow well in Zone 5b with planting dates for Bonner County.
Show all 106 vegetables with planting dates
| Plant | Start Indoors | Direct Sow | Transplant | Harvest | Days to Maturity |
|---|---|---|---|---|---|
| Acorn Squash | Mar 31 | May 12 | May 19 | Aug 11 – Sep 15 | 80–100 |
| Amaranth | Mar 10 | May 12 | May 19 | Aug 18 – Oct 6 | 90–120 |
| Arugula | Mar 31 | Apr 21 | May 5 | Jun 9 – Aug 11 | 30–50 |
| Asparagus | — | — | May 19 | — | 730–1095 |
| Beets | — | Apr 21 | — | Jun 16 – Jul 14 | 50–70 |
| Belgian Endive | Mar 31 | Apr 21 | May 5 | Aug 25 – Oct 20 | 110–150 |
| Bitter Melon | Mar 10 | May 12 | May 19 | Jul 21 – Sep 1 | 60–90 |
| Black Beans | — | May 12 | — | Aug 11 – Sep 29 | 90–120 |
| Bok Choy | Mar 31 | Apr 21 | May 5 | Jun 16 – Jul 21 | 40–60 |
| Broccoli | Mar 31 | Apr 21 | May 5 | Jul 7 – Aug 18 | 60–90 |
| Broccoli Rabe | Mar 31 | Apr 21 | May 5 | Jun 16 – Jul 21 | 40–60 |
| Brussels Sprouts | Mar 31 | Apr 21 | May 5 | Aug 4 – Sep 29 | 90–130 |
| Butternut Squash | Mar 31 | May 12 | May 19 | Aug 18 – Sep 22 | 85–110 |
| Cabbage | Mar 31 | Apr 21 | May 5 | Jul 7 – Sep 1 | 60–100 |
| Calabash | Mar 10 | May 12 | May 19 | Aug 11 – Oct 6 | 80–120 |
| Carrots | — | Apr 21 | — | Jun 23 – Jul 28 | 60–80 |
| Cauliflower | Mar 31 | Apr 21 | May 5 | Jun 30 – Sep 1 | 55–100 |
| Celeriac | Mar 31 | Apr 21 | May 5 | Aug 18 – Sep 22 | 100–120 |
| Celery | Mar 31 | Apr 21 | May 5 | Jul 28 – Sep 22 | 80–120 |
| Celtuce | Mar 31 | Apr 21 | May 5 | Jul 7 – Aug 18 | 60–90 |
| Chard | Mar 31 | Apr 21 | May 5 | Jun 30 – Aug 18 | 50–60 |
| Chickpeas | Mar 31 | Apr 21 | May 5 | Jul 28 – Sep 8 | 80–110 |
| Chicory | Mar 31 | Apr 21 | May 5 | Jul 7 – Aug 18 | 60–85 |
| Chinese Cabbage | Mar 31 | Apr 21 | May 5 | Jun 30 – Jul 28 | 50–70 |
| Christmas Lima Beans | Mar 10 | May 12 | May 19 | Aug 11 – Sep 15 | 80–100 |
| Collard Greens | Mar 31 | Apr 21 | May 5 | Jun 30 – Sep 1 | 55–75 |
| Corn | — | May 12 | — | Jul 14 – Sep 8 | 60–100 |
| Cowpeas | — | May 12 | — | Jul 14 – Aug 25 | 60–90 |
| Cress | Mar 31 | Apr 21 | May 5 | May 19 – Jun 9 | 14–21 |
| Crookneck Squash | Mar 31 | May 12 | May 19 | Jul 7 – Aug 4 | 45–60 |
| Crosne | — | Apr 21 | — | Sep 22 – Oct 6 | 150–200 |
| Cucumber | Mar 31 | May 12 | May 19 | Jul 14 – Sep 8 | 50–70 |
| Daikon | — | Apr 21 | — | Jun 16 – Jul 14 | 50–70 |
| Delicata Squash | Mar 31 | May 12 | May 19 | Aug 11 – Sep 15 | 80–100 |
| Edamame | — | May 12 | — | Jul 28 – Sep 8 | 75–100 |
| Eggplant | Feb 24 | May 12 | May 19 | Jul 28 – Sep 29 | 65–85 |
| Endive | Mar 31 | Apr 21 | May 5 | Jun 23 – Jul 28 | 45–65 |
| Escarole | Mar 31 | Apr 21 | May 5 | Jun 30 – Jul 28 | 50–70 |
| Fava Beans | Mar 31 | Apr 21 | May 5 | Jul 21 – Sep 1 | 75–100 |
| Fennel | Mar 10 | May 12 | May 19 | Jul 21 – Sep 1 | 60–90 |
| Garlic | — | — | — | — | 90–240 |
| Green Beans | — | May 12 | — | Jul 7 – Sep 1 | 50–65 |
| Horseradish | — | — | May 19 | Sep 22 – Nov 3 | 120–180 |
| Hot Peppers | Feb 24 | May 12 | May 19 | Jul 28 – Nov 3 | 70–120 |
| Hubbard Squash | Mar 31 | May 12 | May 19 | Sep 1 – Oct 6 | 100–120 |
| Kabocha | Mar 31 | May 12 | May 19 | Aug 18 – Sep 15 | 85–100 |
| Kai Lan | Mar 31 | Apr 21 | May 5 | Jun 23 – Jul 21 | 45–60 |
| Kale | Mar 31 | Apr 21 | May 5 | Jun 30 – Aug 25 | 50–70 |
| Kidney Beans | — | May 12 | — | Aug 11 – Sep 15 | 85–110 |
| Kohlrabi | Mar 31 | Apr 21 | May 5 | Jun 23 – Jul 28 | 45–65 |
| Komatsuna | Mar 31 | Apr 21 | May 5 | Jun 9 – Jul 14 | 35–50 |
| Leeks | Mar 31 | Apr 21 | May 5 | Aug 4 – Oct 20 | 90–150 |
| Lentils | Mar 31 | Apr 21 | May 5 | Jul 28 – Sep 8 | 80–110 |
| Lettuce | Mar 31 | Apr 21 | May 5 | Jun 9 – Aug 18 | 30–60 |
| Lima Beans | — | May 12 | — | Jul 14 – Aug 25 | 60–90 |
| Mache | Mar 31 | Apr 21 | May 5 | Jun 16 – Jul 21 | 40–60 |
| Melon | Mar 31 | May 12 | May 19 | Jul 28 – Sep 15 | 70–100 |
| Microgreens | Mar 31 | Apr 21 | May 5 | May 12 – Jun 9 | 7–21 |
| Mitsuba | Mar 31 | Apr 21 | Apr 28 | Jun 23 – Aug 18 | 50–70 |
| Mizuna | Mar 31 | Apr 21 | May 5 | Jun 9 – Jul 7 | 30–45 |
| Mustard Greens | Mar 31 | Apr 21 | May 5 | Jun 9 – Aug 11 | 30–50 |
| Napa Cabbage | Mar 31 | Apr 21 | May 5 | Jun 30 – Aug 4 | 55–75 |
| New Zealand Spinach | Mar 10 | May 12 | May 19 | Jul 14 – Aug 11 | 55–70 |
| Okra | Mar 10 | May 12 | May 19 | Jul 14 – Sep 8 | 50–65 |
| Onion | Mar 31 | Apr 21 | May 5 | Aug 4 – Sep 22 | 90–120 |
| Pac Choi | Mar 31 | Apr 21 | May 5 | Jun 16 – Jul 14 | 40–55 |
| Parsnip | — | Apr 21 | — | Aug 4 – Sep 15 | 100–130 |
| Patty Pan Squash | Mar 31 | May 12 | May 19 | Jul 7 – Aug 4 | 45–60 |
| Peas | Mar 31 | Apr 21 | May 5 | Jun 30 – Aug 25 | 55–70 |
| Peppers | Feb 24 | May 12 | May 19 | Jul 21 – Sep 29 | 60–90 |
| Pole Beans | Mar 10 | May 12 | May 19 | Jul 14 – Sep 8 | 55–70 |
| Potatoes | Mar 10 | May 12 | May 19 | Jul 28 – Oct 6 | 70–120 |
| Pumpkin | Mar 31 | May 12 | May 19 | Aug 18 – Oct 6 | 85–120 |
| Purslane | Mar 31 | Apr 21 | May 5 | Jun 16 – Jul 21 | 40–60 |
| Radicchio | Mar 31 | Apr 21 | May 5 | Jul 7 – Aug 11 | 60–80 |
| Radish | — | Apr 21 | — | May 19 – Jun 9 | 22–35 |
| Rhubarb | — | — | May 26 | — | 365–730 |
| Romanesco | Mar 31 | Apr 21 | May 5 | Jul 21 – Sep 1 | 75–100 |
| Rutabaga | — | Apr 21 | — | Jul 14 – Aug 18 | 80–100 |
| Salsify | — | Apr 21 | — | Aug 4 – Sep 15 | 100–130 |
| Savoy Cabbage | Mar 31 | Apr 21 | May 5 | Jul 14 – Sep 8 | 70–110 |
| Scallions | Mar 31 | Apr 21 | May 5 | Jun 30 – Jul 28 | 50–70 |
| Scarlet Runner Beans | Mar 10 | May 12 | May 19 | Jul 21 – Aug 25 | 60–80 |
| Shallot | Mar 31 | Apr 21 | May 5 | Aug 4 – Sep 22 | 90–120 |
| Shiso | Mar 17 | May 12 | May 19 | Jul 14 – Sep 8 | 50–70 |
| Snap Peas | Mar 10 | May 12 | May 19 | Jul 14 – Sep 8 | 55–70 |
| Snow Peas | Mar 31 | Apr 21 | May 5 | Jun 30 – Aug 25 | 50–65 |
| Soybeans | — | May 12 | — | Aug 4 – Sep 29 | 80–120 |
| Spaghetti Squash | Mar 31 | May 12 | May 19 | Aug 18 – Sep 15 | 85–100 |
| Spinach | Mar 31 | Apr 21 | May 5 | Jun 9 – Aug 11 | 35–50 |
| Squash (Summer) | Mar 31 | May 12 | May 19 | Jul 7 – Sep 8 | 45–65 |
| Squash (Winter) | Mar 31 | May 12 | May 19 | Aug 11 – Oct 6 | 80–120 |
| Sunchoke | — | — | May 19 | Sep 8 – Nov 3 | 110–150 |
| Sunflower | Mar 10 | May 12 | May 19 | Jul 28 – Sep 15 | 70–100 |
| Sweet Corn | — | May 12 | — | Jul 14 – Aug 25 | 60–90 |
| Sweet Potatoes | Mar 10 | May 12 | May 19 | Aug 18 – Oct 6 | 90–120 |
| Tatsoi | Mar 31 | Apr 21 | May 5 | Jun 9 – Jul 14 | 35–50 |
| Tomatillo | Mar 10 | May 12 | May 19 | Jul 21 – Sep 29 | 60–85 |
| Tomatoes | Mar 10 | May 12 | May 19 | Jul 21 – Sep 29 | 60–85 |
| Turnip | — | Apr 21 | — | Jun 2 – Jul 7 | 40–60 |
| Watercress | Mar 31 | Apr 21 | May 5 | Jun 16 – Jul 21 | 40–60 |
| Watermelon | Mar 31 | May 12 | May 19 | Jul 28 – Sep 15 | 70–100 |
| Wax Beans | — | May 12 | — | Jul 7 – Sep 1 | 50–65 |
| Winter Melon | Mar 10 | May 12 | May 19 | Aug 18 – Oct 6 | 90–120 |
| Yard Long Beans | Mar 10 | May 12 | May 19 | Jul 14 – Aug 25 | 55–80 |
| Zucchini | Mar 31 | May 12 | May 19 | Jul 7 – Sep 1 | 45–60 |
🍓 Fruits to Grow in Bonner County
27 fruits that grow well in Zone 5b with planting dates for Bonner County.
Show all 27 fruits with planting dates
| Plant | Start Indoors | Direct Sow | Transplant | Harvest | Days to Maturity |
|---|---|---|---|---|---|
| Alpine Strawberries | — | — | May 26 | Aug 25 – Nov 10 | 90–180 |
| Aronia | — | — | May 26 | — | 730–1095 |
| Blackberries | — | — | May 26 | — | 365–730 |
| Blueberries | — | — | May 26 | — | 730–1095 |
| Boysenberries | — | — | May 26 | — | 365–730 |
| Cantaloupe | — | — | May 26 | Aug 4 – Sep 8 | 70–90 |
| Che Fruit | — | — | May 26 | — | 1095–1825 |
| Cranberries | — | — | May 26 | — | 730–1095 |
| Currants | — | — | May 26 | — | 730–1095 |
| Elderberries | — | — | May 26 | — | 730–1095 |
| Goji Berries | — | — | May 26 | — | 730–1095 |
| Gooseberries | — | — | May 26 | — | 730–1095 |
| Grapes | — | — | May 26 | — | 730–1095 |
| Ground Cherry | — | — | May 26 | Aug 4 – Sep 29 | 65–80 |
| Hardy Kiwi | — | — | May 26 | — | 1095–1825 |
| Haskaps | — | — | May 26 | — | 730–1095 |
| Honeydew | — | — | May 26 | Aug 18 – Sep 29 | 80–110 |
| Jostaberry | — | — | May 26 | — | 730–1095 |
| Lingonberries | — | — | May 26 | — | 730–1095 |
| Medlar | — | — | May 26 | — | 1095–1825 |
| Mulberries | — | — | May 26 | — | 730–1825 |
| Pawpaw | — | — | May 26 | — | 1095–2555 |
| Persimmon | — | — | May 26 | — | 1095–2555 |
| Quince | — | — | May 26 | — | 1095–1825 |
| Raspberries | — | — | May 26 | — | 365–730 |
| Serviceberries | — | — | May 26 | — | 730–1095 |
| Strawberries | — | — | May 26 | Aug 25 – Nov 10 | 90–365 |
🌿 Herbs to Grow in Bonner County
37 herbs that grow well in Zone 5b with planting dates for Bonner County.
Show all 37 herbs with planting dates
| Plant | Start Indoors | Direct Sow | Transplant | Harvest | Days to Maturity |
|---|---|---|---|---|---|
| Angelica | Mar 31 | Apr 21 | Apr 28 | — | 365–730 |
| Anise | Mar 31 | Apr 21 | Apr 28 | Jul 28 – Oct 13 | 90–120 |
| Basil | Mar 17 | May 12 | May 19 | Jul 14 – Sep 15 | 50–75 |
| Bee Balm | — | — | May 12 | Aug 11 – Oct 27 | 90–120 |
| Borage | Mar 31 | Apr 21 | Apr 28 | Jun 23 – Aug 11 | 50–60 |
| Caraway | Mar 31 | Apr 21 | Apr 28 | — | 365–450 |
| Catnip | — | — | May 12 | Jul 14 – Sep 15 | 60–80 |
| Chamomile | Mar 31 | Apr 21 | Apr 28 | Jun 30 – Sep 8 | 60–90 |
| Chervil | Mar 31 | Apr 21 | Apr 28 | Jun 9 – Aug 11 | 40–60 |
| Chives | — | — | May 12 | Jul 14 – Sep 22 | 60–90 |
| Cilantro | Mar 31 | Apr 21 | Apr 28 | Jun 9 – Aug 11 | 40–60 |
| Comfrey | — | — | May 12 | Jul 14 – Sep 22 | 60–90 |
| Cumin | Mar 31 | Apr 21 | Apr 28 | Aug 11 – Oct 13 | 100–120 |
| Dill | Mar 31 | Apr 21 | Apr 28 | Jun 9 – Aug 11 | 40–60 |
| Echinacea | — | — | May 12 | Sep 15 – Oct 27 | 120–180 |
| Epazote | Mar 17 | May 12 | May 19 | Jul 7 – Sep 1 | 45–60 |
| Fennel (herb) | Mar 31 | Apr 21 | Apr 28 | Jun 30 – Sep 8 | 60–90 |
| Feverfew | — | — | May 12 | Aug 11 – Oct 27 | 90–120 |
| Garlic Chives | — | — | May 12 | Jul 14 – Sep 22 | 60–90 |
| Horehound | — | — | May 12 | Jul 28 – Sep 22 | 75–90 |
| Hyssop | — | — | May 12 | Jul 21 – Sep 22 | 70–90 |
| Lavender | — | — | May 12 | Aug 11 – Oct 27 | 90–200 |
| Lemon Balm | — | — | May 12 | Jul 14 – Sep 1 | 60–70 |
| Lemon Thyme | — | — | May 12 | Jul 21 – Sep 22 | 70–90 |
| Lovage | — | — | May 12 | Jul 21 – Sep 22 | 70–90 |
| Mint | — | — | May 12 | Jul 14 – Sep 22 | 60–90 |
| Oregano | — | — | May 12 | Jul 14 – Sep 22 | 60–90 |
| Parsley | Mar 31 | Apr 21 | Apr 28 | Jun 30 – Sep 1 | 60–80 |
| Rue | — | — | May 12 | Jul 21 – Sep 22 | 70–90 |
| Sage | — | — | May 12 | Jul 28 – Sep 22 | 75–90 |
| Savory | — | — | May 12 | Jul 7 – Sep 1 | 50–70 |
| Sorrel | Mar 31 | Apr 21 | Apr 28 | Jun 9 – Aug 11 | 40–60 |
| Tarragon | — | — | May 12 | Jul 14 – Sep 22 | 60–90 |
| Thai Basil | Mar 17 | May 12 | May 19 | Jul 14 – Sep 15 | 50–75 |
| Thyme | — | — | May 12 | Jul 21 – Sep 22 | 70–90 |
| Valerian | — | — | May 12 | Sep 15 – Oct 27 | 120–180 |
| Yarrow | — | — | May 12 | Aug 11 – Oct 27 | 90–120 |
Monthly Planting Guide for Bonner County
Gardening Guides & Resources
Helpful guides from The Ultimate Homestead to improve your garden in Bonner County.
Frequently Asked Questions
What planting zone is Bonner County, ID?
Bonner County is in USDA Hardiness Zone 5b. This zone classification determines which perennial plants survive winter and sets the baseline for frost timing across the county.
When is the last frost in Bonner County, ID?
Based on 31 years of NOAA weather station data, the median last spring frost in Bonner County falls around May 5. In 8 out of 10 years, last frost lands between April 15 and June 1 — a 46-day window of variability. Use June 1 as your conservative safe-to-plant date for frost-sensitive crops.
When is the first fall frost in Bonner County, ID?
The median first fall frost in Bonner County arrives around October 3. In cold years it can arrive as early as September 3; in mild years as late as October 25. Harvest or protect frost-sensitive crops — tomatoes, peppers, basil, squash — before this date.
How long is the growing season in Bonner County?
Bonner County has a frost-free growing season of approximately 151 days. This is enough time for most warm-season crops including tomatoes, peppers, and squash with proper timing. Climate records show the growing season is trending longer by about 1.77 days per decade.
What is the soil like in Bonner County for gardening?
Bonner County has predominantly Loam soil with a pH range of 6.4–8.2 and Moderately Well Drained drainage. Most vegetables and herbs grow well with standard composting and seasonal soil amendment.
What is grown commercially in Bonner County?
Bonner County has commercial agriculture that includes Potatoes, Wheat, Hay, Cattle, Barley. These crops reflect the local climate and soil conditions — what succeeds commercially often translates well to home gardens in the same area.
Is Bonner County a good location for home gardening?
Bonner County scores 29/100 (Challenging) on our Microclimate Index, which combines frost reliability, drought pressure, soil challenge, elevation risk, and long-term climate trend. Gardening here benefits from close attention to frost timing and season extension due to the challenging microclimate factors.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Bonner County gardeners in Zone 5b organize planting dates, track what's growing, and never miss a planting window.
Get Your Free Garden Planner →Free download. Plan your entire garden season in minutes.
