Boundary County, ID — Planting Guide
Boundary County is in USDA Zone 6a. The average last spring frost is May 10 and the first fall frost is September 22, giving you a growing season of approximately 135 days.
At an elevation of 5,105 ft, Boundary County receives approximately 21.1 in of rainfall annually. Summer highs average 87°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 43 days year to year — ranging from April 22 in warm years to June 4 in cold years. The growing season is trending longer by about 3.05 days per decade. Boundary County scores 36/100 (Challenging) on the Microclimate Index.
🌡️ Zone
6a (-10°F to -5°F min)
❄️ Last Frost
May 10
🍂 First Frost
September 22
📅 Growing Season
135 days
⛰️ Elevation
5,105 ft
🌧️ Annual Rainfall
21.1 in
Monthly Watering Calendar for Boundary County
When you'll need to water your garden — based on average monthly rainfall vs. the ~1 inch/week most gardens need.
Quick context: Watering math is simple: 1 inch of rainfall delivers ~600 gallons to a 1,000 sq ft garden. Boundary County's 21" annual rainfall covers some months entirely; others need a few hours of drip irrigation per week. The calendar tells you which is which.
View detailed monthly data
| Month | Avg Rainfall | Rainy Days | Extra Water Needed | Watering Effort |
|---|---|---|---|---|
| Jan | 1.6 in | 7 days | — | None |
| Feb | 1.2 in | 5 days | — | None |
| Mar | 1.9 in | 8 days | — | None |
| Apr | 2 in | 7 days | 2.3 in | High |
| May | 2.7 in | 8 days | 1.6 in | High |
| Jun | 1.6 in | 5 days | 2.7 in | High |
| Jul | 1.8 in | 6 days | 2.5 in | High |
| Aug | 1.9 in | 6 days | 2.4 in | High |
| Sep | 1.6 in | 5 days | 2.7 in | High |
| Oct | 2.1 in | 6 days | 2.2 in | High |
| Nov | 1.5 in | 6 days | — | None |
| Dec | 1.3 in | 6 days | — | None |
Annual total: 21.2 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.
Boundary County Soil Profile
Soil Type
Loam
Soil pH
6.7-8.3
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 4 | Oct 14 | 132 days |
| Cautious | May 19 | Oct 3 | 137 days |
| Average year | May 10 | Sep 22 | 135 days |
| Optimistic | May 1 | Sep 15 | 137 days |
| Aggressive (risky) | Apr 22 | Sep 1 | 132 days |
Not very — frost dates can vary by ±43 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 3.1 days per decade). Spring is arriving earlier than it used to. Good news for gardeners.
Gardening Difficulty Score
Boundary County has challenging growing conditions. Season extension and careful variety selection are essential.
Local Gardening Help in Boundary 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 Boundary County's climate and soil.
County Extension Office
Boundary 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 Boundary County
Finding local nurseries & garden centers in Boundary County
Why Buy Local
Local nurseries carry plants that are proven to grow in your area. Staff can give you advice specific to Boundary 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 Boundary County ID" or "garden center Boundary 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 Boundary County ID" or check your extension office and local parks department. Facebook groups like "Boundary 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 in Boundary County
Monthly daylight hours and peak sun — critical for onion varieties, photoperiod-sensitive plants, and solar garden planning.
Why it matters: Onions are a great example of why day length matters. They "bulb up" only when daylight hits a specific number of hours — plant the wrong variety (short-day in the north, long-day in the south) and you'll get tiny bulbs no matter how well you grow them. Boundary County's latitude determines which onion varieties succeed.
Longest Day
15.9 hours
Summer solstice daylight
Shortest Day
8.1 hours
Winter solstice daylight
Peak Sun Hours
11.7 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 | 8.5 hr | 4.9 hr | Short day |
| February | 9.9 hr | 6 hr | Short day |
| March | 11.6 hr | 7 hr | Short day |
| April | 13.5 hr | 7.7 hr | Neutral |
| May | 15 hr | 9.4 hr | Long day |
| June | 15.9 hr | 11.7 hr | Long day |
| July | 15.6 hr | 10.7 hr | Long day |
| August | 14.2 hr | 9.3 hr | Long day |
| September | 12.3 hr | 8.9 hr | Neutral |
| October | 10.5 hr | 7 hr | Short day |
| November | 8.9 hr | 5.3 hr | Short day |
| December | 8.1 hr | 4.6 hr | Short day |
Peak sun hours factor in typical cloud cover — use these for solar panel and shade-planning calculations.
Soil Temperature & Composting in Boundary County
Monthly soil temps tell you when to plant warm-season crops, and when your compost pile is actively working.
Quick context: Soil temperature predicts plant emergence better than calendar dates. Boundary County's spring soil warm-up curve tells you which weeks are safe for direct-sow beans, cucumbers, squash, and corn.
Plant Warm Crops When
Soil reaches 60°F+
Soil warm enough from Jul through Aug.
Best Month to Compost
Jun
Microbial activity peaks when soil is warm.
Active Composting
4 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 | 9°F | 17°F | ❄️ Dormant | ~36 weeks |
| Feb | 8°F | 14°F | ❄️ Dormant | ~36 weeks |
| Mar | 17°F | 20°F | ❄️ Dormant | ~36 weeks |
| Apr | 29°F | 28°F | ❄️ Dormant | ~36 weeks |
| May | 44°F | 40°F | 🐢 Slow | ~24 weeks |
| Jun | 55°F | 49°F | ♻️ Active | ~14 weeks |
| Jul | 62°F | 56°F | ♻️ Active | ~14 weeks |
| Aug | 61°F | 57°F | ♻️ Active | ~14 weeks |
| Sep | 55°F | 53°F | ♻️ Active | ~14 weeks |
| Oct | 44°F | 46°F | 🐢 Slow | ~24 weeks |
| Nov | 28°F | 34°F | ❄️ Dormant | ~36 weeks |
| Dec | 16°F | 21°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 Boundary County
Computed from local climate patterns — warmer, humid conditions increase pest generations and fungal disease risk.
Quick context: The most successful gardeners in high-pressure regions don't spray more — they design around the problem. Crop rotation, companion planting, and resistant varieties beat reactive spraying.
Insect Pest Pressure
Moderate — common pests appear but manageable with monitoring.
Disease Risk
Low disease risk — dry conditions reduce fungal problems.
Seasonal Risk
View 5 common pests in your area
| Pest | Risk Level | Peak Months |
|---|---|---|
| Aphids | Moderate | May, Jun, Jul, Aug |
| Japanese beetles | Moderate | Jun, Jul, Aug |
| Squash bugs | Moderate | Jun, Jul, Aug |
| Tomato hornworms | Moderate | Jul, Aug |
| Cabbage loopers | Low | May, Jun, Jul, Aug |
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 Boundary County
Cover crops protect bare soil, fix nitrogen, suppress weeds, and improve soil structure — with planting dates calibrated for your area.
Why this matters: A fall-planted cover crop in Boundary County is the closest thing to free soil amendment. Plant cereal rye or hairy vetch after harvest; chop it down before it flowers in spring; the soil it leaves behind out-grows any store-bought compost.
Spring Cover Crops (3 options) — Build soil before the main growing season
| Crop | Plant By | Terminate | N-Fixing | Soil Benefit |
|---|---|---|---|---|
| Buckwheat | May 17 | Jul 28 | — | Rapid growth, attracts pollinators, suppresses weeds |
| Sorghum-sudan grass | May 15 | Jul 14 | — | Massive biomass, breaks compaction, suppresses nematodes |
| White clover | Apr 13 | Jul 14 | ✓ 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 26 | Aug 25 | — | 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 | Jul 15 | Apr 26 | ✓ Yes | Fixes nitrogen, good for heavy clay soils |
| Daikon radish | Jul 30 | Apr 26 | — | Deep taproot breaks compaction, excellent for clay soils |
| Hairy vetch | Jul 2 | Apr 19 | ✓ Yes | Excellent nitrogen fixer, good for depleted soils |
| Oats | Aug 23 | Apr 19 | — | Quick biomass, winterkills in cold zones — no spring tillage needed |
| Winter rye | Jun 26 | Apr 19 | — | Suppresses weeds, prevents erosion, breaks up compacted soil |
| Winter wheat | Jun 22 | Apr 26 | — | Erosion control, weed suppression, good biomass |
Wind & Microclimate in Boundary County
For new gardeners: Why care about wind? Above about 10 mph, evaporation jumps and pollinators struggle to land on flowers. Boundary County's 11.8 mph average means you can plant tall crops without much support, but it doesn't mean ignore wind — a 20+ mph storm still snaps unstaked tomatoes.
Wind dries soil, stresses plants, and affects frost patterns. Understanding your exposure helps with garden placement.
Seasonal Wind Speed
Spring: 16 mph Summer: 12 mph
Fall: 12 mph Winter: 14 mph
Prevailing wind: W. Windy area — plant a windbreak hedge on the W side of your garden.
Windbreak Benefit
7.1/10
Strongly recommended — a windbreak (fence, hedge, or row of tall crops like corn or sunflowers) will significantly improve garden yields.
Frost Pocket Risk
High
Hilly terrain with 2,279 ft of elevation range — cold air pools in low spots. Avoid planting frost-sensitive crops in valleys.
Rainwater Harvesting in Boundary County
How much water you can collect, when to collect it, and what size system you need for your garden.
For new gardeners: A gravity-fed rain barrel ($75) is the easy entry. A larger cistern ($500-1500) covers a whole growing season. Boundary County's 21" annual rainfall determines whether the larger system is overkill or essential.
Annual Collection
10,566 gal
Per 1,000 sq ft of roof area (at 80% collection efficiency)
Recommended Setup
7 rain barrels (55 gal each)
For a typical 500 sq ft garden. Serious collectors: consider a 1,750 gal tank.
Legal Status
Unrestricted
Rainwater harvesting is fully legal in your state with no restrictions.
Best Collection Months
Mar, Apr, May, Oct
Highest rainfall months — your barrels will fill up quickly during these months.
Months to Draw From Storage
Feb, 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 21.2 inches of rain per year
- A 1,000 sq ft roof can collect roughly 10,566 gallons annually
- Rainwater harvesting is fully legal in your state
- Stock up on stored water before your dry season (Feb, Nov, Dec)
- Use a first-flush diverter to keep roof debris out of your collection
Soil & Growing Conditions in Boundary County
Soil Type
Loam
Soil pH 6.7–8.3 · Well Drained drainage
Native soil is well-suited to most vegetables and herbs with regular compost additions.
Watering Needs
Drought stress: 5.5/10
Moderate drought pressure. Drip irrigation and mulching are highly recommended to maintain soil moisture through summer.
Season Tips
135-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.
Your Free Printable Garden Planner
Plan every bed, every planting, every harvest — in one place. This 22-page printable includes your zone's planting calendar, a month-by-month task list, a seed inventory tracker, a harvest log, and succession-planting charts. Built to print, write in, and actually use all season.
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 Boundary County
107 vegetables that grow well in Zone 6a with planting dates for Boundary County.
Show all 107 vegetables with planting dates
| Plant | Start Indoors | Direct Sow | Transplant | Fall Plant | Harvest | Days to Maturity |
|---|---|---|---|---|---|---|
| Acorn Squash | Apr 5 | May 17 | May 24 | — | Aug 16 – Sep 20 | 80–100 |
| Amaranth | Mar 15 | May 17 | May 24 | — | Aug 23 – Oct 11 | 90–120 |
| Arugula | Apr 5 | Apr 26 | May 10 | Jul 14 | Jun 14 – Aug 16 | 30–50 |
| Asparagus | — | — | May 24 | — | — | 730–1095 |
| Beets | — | Apr 26 | — | Jul 14 | Jun 21 – Jul 19 | 50–70 |
| Belgian Endive | Apr 5 | Apr 26 | May 10 | Jul 14 | Aug 30 – Oct 25 | 110–150 |
| Bitter Melon | Mar 15 | May 17 | May 24 | — | Jul 26 – Sep 6 | 60–90 |
| Black Beans | — | May 17 | — | — | Aug 16 – Oct 4 | 90–120 |
| Bok Choy | Apr 5 | Apr 26 | May 10 | Jul 14 | Jun 21 – Jul 26 | 40–60 |
| Broccoli | Apr 5 | Apr 26 | May 10 | Jul 14 | Jul 12 – Aug 23 | 60–90 |
| Broccoli Rabe | Apr 5 | Apr 26 | May 10 | Jul 14 | Jun 21 – Jul 26 | 40–60 |
| Brussels Sprouts | Apr 5 | Apr 26 | May 10 | Jul 14 | Aug 9 – Oct 4 | 90–130 |
| Butternut Squash | Apr 5 | May 17 | May 24 | — | Aug 23 – Sep 27 | 85–110 |
| Cabbage | Apr 5 | Apr 26 | May 10 | Jul 14 | Jul 12 – Sep 6 | 60–100 |
| Calabash | Mar 15 | May 17 | May 24 | — | Aug 16 – Oct 11 | 80–120 |
| Carrots | — | Apr 26 | — | Jul 14 | Jun 28 – Aug 2 | 60–80 |
| Cauliflower | Apr 5 | Apr 26 | May 10 | Jul 14 | Jul 5 – Sep 6 | 55–100 |
| Celeriac | Apr 5 | Apr 26 | May 10 | Jul 14 | Aug 23 – Sep 27 | 100–120 |
| Celery | Apr 5 | Apr 26 | May 10 | Jul 14 | Aug 2 – Sep 27 | 80–120 |
| Celtuce | Apr 5 | Apr 26 | May 10 | Jul 14 | Jul 12 – Aug 23 | 60–90 |
| Chard | Apr 5 | Apr 26 | May 10 | Jul 14 | Jul 5 – Aug 23 | 50–60 |
| Chickpeas | Apr 5 | Apr 26 | May 10 | Jul 14 | Aug 2 – Sep 13 | 80–110 |
| Chicory | Apr 5 | Apr 26 | May 10 | Jul 14 | Jul 12 – Aug 23 | 60–85 |
| Chinese Cabbage | Apr 5 | Apr 26 | May 10 | Jul 14 | Jul 5 – Aug 2 | 50–70 |
| Christmas Lima Beans | Mar 15 | May 17 | May 24 | — | Aug 16 – Sep 20 | 80–100 |
| Collard Greens | Apr 5 | Apr 26 | May 10 | Jul 14 | Jul 5 – Sep 6 | 55–75 |
| Corn | — | May 17 | — | — | Jul 19 – Sep 13 | 60–100 |
| Cowpeas | — | May 17 | — | — | Jul 19 – Aug 30 | 60–90 |
| Cress | Apr 5 | Apr 26 | May 10 | Jul 14 | May 24 – Jun 14 | 14–21 |
| Crookneck Squash | Apr 5 | May 17 | May 24 | — | Jul 12 – Aug 9 | 45–60 |
| Crosne | — | Apr 26 | — | Jul 14 | Sep 27 – Nov 8 | 150–200 |
| Cucumber | Apr 5 | May 17 | May 24 | — | Jul 19 – Sep 13 | 50–70 |
| Daikon | — | Apr 26 | — | Jul 14 | Jun 21 – Jul 19 | 50–70 |
| Delicata Squash | Apr 5 | May 17 | May 24 | — | Aug 16 – Sep 20 | 80–100 |
| Edamame | — | May 17 | — | — | Aug 2 – Sep 13 | 75–100 |
| Eggplant | Mar 1 | May 17 | May 24 | — | Aug 2 – Oct 4 | 65–85 |
| Endive | Apr 5 | Apr 26 | May 10 | Jul 14 | Jun 28 – Aug 2 | 45–65 |
| Escarole | Apr 5 | Apr 26 | May 10 | Jul 14 | Jul 5 – Aug 2 | 50–70 |
| Fava Beans | Apr 5 | Apr 26 | May 10 | Jul 14 | Jul 26 – Sep 6 | 75–100 |
| Fennel | Mar 15 | May 17 | May 24 | — | Jul 26 – Sep 6 | 60–90 |
| Garlic | — | — | — | Aug 11 | Nov 10 – Feb 23 | 90–240 |
| Green Beans | — | May 17 | — | — | Jul 12 – Sep 6 | 50–65 |
| Horseradish | — | — | May 24 | — | Sep 27 – Dec 6 | 120–180 |
| Hot Peppers | Mar 1 | May 17 | May 24 | — | Aug 2 – Nov 8 | 70–120 |
| Hubbard Squash | Apr 5 | May 17 | May 24 | — | Sep 6 – Oct 11 | 100–120 |
| Kabocha | Apr 5 | May 17 | May 24 | — | Aug 23 – Sep 20 | 85–100 |
| Kai Lan | Apr 5 | Apr 26 | May 10 | Jul 14 | Jun 28 – Jul 26 | 45–60 |
| Kale | Apr 5 | Apr 26 | May 10 | Jul 14 | Jul 5 – Aug 30 | 50–70 |
| Kidney Beans | — | May 17 | — | — | Aug 16 – Sep 20 | 85–110 |
| Kohlrabi | Apr 5 | Apr 26 | May 10 | Jul 14 | Jun 28 – Aug 2 | 45–65 |
| Komatsuna | Apr 5 | Apr 26 | May 10 | Jul 14 | Jun 14 – Jul 19 | 35–50 |
| Leeks | Apr 5 | Apr 26 | May 10 | Jul 14 | Aug 9 – Oct 25 | 90–150 |
| Lentils | Apr 5 | Apr 26 | May 10 | Jul 14 | Aug 2 – Sep 13 | 80–110 |
| Lettuce | Apr 5 | Apr 26 | May 10 | Jul 14 | Jun 14 – Aug 23 | 30–60 |
| Lima Beans | — | May 17 | — | — | Jul 19 – Aug 30 | 60–90 |
| Loofah | Mar 15 | May 17 | May 24 | — | Sep 6 – Nov 8 | 100–150 |
| Luffa | Mar 15 | May 17 | May 24 | — | Aug 23 – Nov 8 | 90–150 |
| Mache | Apr 5 | Apr 26 | May 10 | Jul 14 | Jun 21 – Jul 26 | 40–60 |
| Melon | Apr 5 | May 17 | May 24 | — | Aug 2 – Sep 20 | 70–100 |
| Microgreens | Apr 5 | Apr 26 | May 10 | Jul 14 | May 17 – Jun 14 | 7–21 |
| Mitsuba | Apr 5 | Apr 26 | May 3 | Jul 14 | Jun 28 – Aug 23 | 50–70 |
| Mizuna | Apr 5 | Apr 26 | May 10 | Jul 14 | Jun 14 – Jul 12 | 30–45 |
| Mustard Greens | Apr 5 | Apr 26 | May 10 | Jul 14 | Jun 14 – Aug 16 | 30–50 |
| Napa Cabbage | Apr 5 | Apr 26 | May 10 | Jul 14 | Jul 5 – Aug 9 | 55–75 |
| New Zealand Spinach | Mar 15 | May 17 | May 24 | — | Jul 19 – Aug 16 | 55–70 |
| Okra | Mar 15 | May 17 | May 24 | — | Jul 19 – Sep 13 | 50–65 |
| Onion | Apr 5 | Apr 26 | May 10 | Jul 14 | Aug 9 – Sep 27 | 90–120 |
| Pac Choi | Apr 5 | Apr 26 | May 10 | Jul 14 | Jun 21 – Jul 19 | 40–55 |
| Parsnip | — | Apr 26 | — | Jul 14 | Aug 9 – Sep 20 | 100–130 |
| Patty Pan Squash | Apr 5 | May 17 | May 24 | — | Jul 12 – Aug 9 | 45–60 |
| Peas | Apr 5 | Apr 26 | May 10 | Jul 14 | Jul 5 – Aug 30 | 55–70 |
| Peppers | Mar 1 | May 17 | May 24 | — | Jul 26 – Oct 4 | 60–90 |
| Pole Beans | Mar 15 | May 17 | May 24 | — | Jul 19 – Sep 13 | 55–70 |
| Potatoes | Mar 15 | May 17 | May 24 | — | Aug 2 – Oct 11 | 70–120 |
| Pumpkin | Apr 5 | May 17 | May 24 | — | Aug 23 – Oct 11 | 85–120 |
| Purslane | Apr 5 | Apr 26 | May 10 | Jul 14 | Jun 21 – Jul 26 | 40–60 |
| Radicchio | Apr 5 | Apr 26 | May 10 | Jul 14 | Jul 12 – Aug 16 | 60–80 |
| Radish | — | Apr 26 | — | Jul 14 | May 24 – Jun 14 | 22–35 |
| Rhubarb | — | — | May 31 | — | — | 365–730 |
| Romanesco | Apr 5 | Apr 26 | May 10 | Jul 14 | Jul 26 – Sep 6 | 75–100 |
| Rutabaga | — | Apr 26 | — | Jul 14 | Jul 19 – Aug 23 | 80–100 |
| Salsify | — | Apr 26 | — | Jul 14 | Aug 9 – Sep 20 | 100–130 |
| Savoy Cabbage | Apr 5 | Apr 26 | May 10 | Jul 14 | Jul 19 – Sep 13 | 70–110 |
| Scallions | Apr 5 | Apr 26 | May 10 | Jul 14 | Jul 5 – Aug 2 | 50–70 |
| Scarlet Runner Beans | Mar 15 | May 17 | May 24 | — | Jul 26 – Aug 30 | 60–80 |
| Shallot | Apr 5 | Apr 26 | May 10 | Jul 14 | Aug 9 – Sep 27 | 90–120 |
| Shiso | Mar 22 | May 17 | May 24 | — | Jul 19 – Sep 13 | 50–70 |
| Snap Peas | Mar 15 | May 17 | May 24 | — | Jul 19 – Sep 13 | 55–70 |
| Snow Peas | Apr 5 | Apr 26 | May 10 | Jul 14 | Jul 5 – Aug 30 | 50–65 |
| Soybeans | — | May 17 | — | — | Aug 9 – Oct 4 | 80–120 |
| Spaghetti Squash | Apr 5 | May 17 | May 24 | — | Aug 23 – Sep 20 | 85–100 |
| Spinach | Apr 5 | Apr 26 | May 10 | Jul 14 | Jun 14 – Aug 16 | 35–50 |
| Squash (Summer) | Apr 5 | May 17 | May 24 | — | Jul 12 – Sep 13 | 45–65 |
| Squash (Winter) | Apr 5 | May 17 | May 24 | — | Aug 16 – Oct 11 | 80–120 |
| Sunchoke | — | — | May 24 | — | Sep 13 – Nov 8 | 110–150 |
| Sweet Corn | — | May 17 | — | — | Jul 19 – Aug 30 | 60–90 |
| Sweet Potatoes | Mar 15 | May 17 | May 24 | — | Aug 23 – Oct 11 | 90–120 |
| Tatsoi | Apr 5 | Apr 26 | May 10 | Jul 14 | Jun 14 – Jul 19 | 35–50 |
| Tomatillo | Mar 15 | May 17 | May 24 | — | Jul 26 – Oct 4 | 60–85 |
| Tomatoes | Mar 15 | May 17 | May 24 | — | Jul 26 – Oct 4 | 60–85 |
| Turnip | — | Apr 26 | — | Jul 14 | Jun 7 – Jul 12 | 40–60 |
| Watercress | Apr 5 | Apr 26 | May 10 | Jul 14 | Jun 21 – Jul 26 | 40–60 |
| Watermelon | Apr 5 | May 17 | May 24 | — | Aug 2 – Sep 20 | 70–100 |
| Wax Beans | — | May 17 | — | — | Jul 12 – Sep 6 | 50–65 |
| Winter Melon | Mar 15 | May 17 | May 24 | — | Aug 23 – Oct 11 | 90–120 |
| Yard Long Beans | Mar 15 | May 17 | May 24 | — | Jul 19 – Aug 30 | 55–80 |
| Zucchini | Apr 5 | May 17 | May 24 | — | Jul 12 – Sep 6 | 45–60 |
🍓 Fruits to Grow in Boundary County
27 fruits that grow well in Zone 6a with planting dates for Boundary County.
Show all 27 fruits with planting dates
| Plant | Start Indoors | Direct Sow | Transplant | Fall Plant | Harvest | Days to Maturity |
|---|---|---|---|---|---|---|
| Alpine Strawberries | — | — | May 31 | — | Aug 30 – Dec 13 | 90–180 |
| Aronia | — | — | May 31 | — | — | 730–1095 |
| Blackberries | — | — | May 31 | — | — | 365–730 |
| Blueberries | — | — | May 31 | — | — | 730–1095 |
| Boysenberries | — | — | May 31 | — | — | 365–730 |
| Cantaloupe | — | — | May 31 | — | Aug 9 – Sep 13 | 70–90 |
| Che Fruit | — | — | May 31 | — | — | 1095–1825 |
| Cranberries | — | — | May 31 | — | — | 730–1095 |
| Currants | — | — | May 31 | — | — | 730–1095 |
| Elderberries | — | — | May 31 | — | — | 730–1095 |
| Goji Berries | — | — | May 31 | — | — | 730–1095 |
| Gooseberries | — | — | May 31 | — | — | 730–1095 |
| Grapes | — | — | May 31 | — | — | 730–1095 |
| Ground Cherry | — | — | May 31 | — | Aug 9 – Oct 4 | 65–80 |
| Hardy Kiwi | — | — | May 31 | — | — | 1095–1825 |
| Haskaps | — | — | May 31 | — | — | 730–1095 |
| Honeydew | — | — | May 31 | — | Aug 23 – Oct 4 | 80–110 |
| Jostaberry | — | — | May 31 | — | — | 730–1095 |
| Lingonberries | — | — | May 31 | — | — | 730–1095 |
| Medlar | — | — | May 31 | — | — | 1095–1825 |
| Mulberries | — | — | May 31 | — | — | 730–1825 |
| Pawpaw | — | — | May 31 | — | — | 1095–2555 |
| Persimmon | — | — | May 31 | — | — | 1095–2555 |
| Quince | — | — | May 31 | — | — | 1095–1825 |
| Raspberries | — | — | May 31 | — | — | 365–730 |
| Serviceberries | — | — | May 31 | — | — | 730–1095 |
| Strawberries | — | — | May 31 | — | Aug 30 – Dec 13 | 90–365 |
🌿 Herbs to Grow in Boundary County
35 herbs that grow well in Zone 6a with planting dates for Boundary County.
Show all 35 herbs with planting dates
| Plant | Start Indoors | Direct Sow | Transplant | Fall Plant | Harvest | Days to Maturity |
|---|---|---|---|---|---|---|
| Angelica | Apr 5 | Apr 26 | May 3 | Jul 14 | — | 365–730 |
| Anise | Apr 5 | Apr 26 | May 3 | Jul 14 | Aug 2 – Oct 18 | 90–120 |
| Basil | Mar 22 | May 17 | May 24 | — | Jul 19 – Sep 20 | 50–75 |
| Bee Balm | — | — | May 17 | — | Aug 16 – Nov 1 | 90–120 |
| Borage | Apr 5 | Apr 26 | May 3 | Jul 14 | Jun 28 – Aug 16 | 50–60 |
| Caraway | Apr 5 | Apr 26 | May 3 | Jul 14 | — | 365–450 |
| Catnip | — | — | May 17 | — | Jul 19 – Sep 20 | 60–80 |
| Chamomile | Apr 5 | Apr 26 | May 3 | Jul 14 | Jul 5 – Sep 13 | 60–90 |
| Chervil | Apr 5 | Apr 26 | May 3 | Jul 14 | Jun 14 – Aug 16 | 40–60 |
| Chives | — | — | May 17 | — | Jul 19 – Sep 27 | 60–90 |
| Cilantro | Apr 5 | Apr 26 | May 3 | Jul 14 | Jun 14 – Aug 16 | 40–60 |
| Comfrey | — | — | May 17 | — | Jul 19 – Sep 27 | 60–90 |
| Cumin | Apr 5 | Apr 26 | May 3 | Jul 14 | Aug 16 – Oct 18 | 100–120 |
| Dill | Apr 5 | Apr 26 | May 3 | Jul 14 | Jun 14 – Aug 16 | 40–60 |
| Epazote | Mar 22 | May 17 | May 24 | — | Jul 12 – Sep 6 | 45–60 |
| Fennel (herb) | Apr 5 | Apr 26 | May 3 | Jul 14 | Jul 5 – Sep 13 | 60–90 |
| Feverfew | — | — | May 17 | — | Aug 16 – Nov 1 | 90–120 |
| Garlic Chives | — | — | May 17 | — | Jul 19 – Sep 27 | 60–90 |
| Horehound | — | — | May 17 | — | Aug 2 – Sep 27 | 75–90 |
| Hyssop | — | — | May 17 | — | Jul 26 – Sep 27 | 70–90 |
| Lemon Balm | — | — | May 17 | — | Jul 19 – Sep 6 | 60–70 |
| Lemon Thyme | — | — | May 17 | — | Jul 26 – Sep 27 | 70–90 |
| Lovage | — | — | May 17 | — | Jul 26 – Sep 27 | 70–90 |
| Marjoram | — | — | May 17 | — | Jul 19 – Sep 27 | 60–90 |
| Mint | — | — | May 17 | — | Jul 19 – Sep 27 | 60–90 |
| Oregano | — | — | May 17 | — | Jul 19 – Sep 27 | 60–90 |
| Parsley | Apr 5 | Apr 26 | May 3 | Jul 14 | Jul 5 – Sep 6 | 60–80 |
| Rue | — | — | May 17 | — | Jul 26 – Sep 27 | 70–90 |
| Sage | — | — | May 17 | — | Aug 2 – Sep 27 | 75–90 |
| Savory | — | — | May 17 | — | Jul 12 – Sep 6 | 50–70 |
| Sorrel | Apr 5 | Apr 26 | May 3 | Jul 14 | Jun 14 – Aug 16 | 40–60 |
| Tarragon | — | — | May 17 | — | Jul 19 – Sep 27 | 60–90 |
| Thai Basil | Mar 22 | May 17 | May 24 | — | Jul 19 – Sep 20 | 50–75 |
| Thyme | — | — | May 17 | — | Jul 26 – Sep 27 | 70–90 |
| Valerian | — | — | May 17 | — | Sep 20 – Nov 29 | 120–180 |
🌸 Flowers to Grow in Boundary County
53 flowers that grow well in Zone 6a with planting dates for Boundary County.
Show all 53 flowers with planting dates
| Plant | Start Indoors | Direct Sow | Transplant | Fall Plant | Bloom | Days to Maturity |
|---|---|---|---|---|---|---|
| Ageratum | Mar 22 | May 10 | May 10 | — | Jul 5 – Oct 11 | 60–75 |
| Alliums | — | — | — | Aug 11 | Sep 8 – Oct 6 | 28–42 |
| Anemones | Apr 12 | — | May 10 | — | Jun 14 – Jul 12 | 90–120 |
| Astilbe | Mar 8 | — | May 17 | — | Jul 26 – Oct 4 | 70–100 |
| Bachelor's Button | Mar 29 | Apr 12 | May 10 | Aug 11 | Jul 12 – Sep 27 | 60–90 |
| Begonias | Mar 1 | — | May 17 | — | Jul 26 – Oct 25 | 70–90 |
| Black-eyed Susan | Mar 8 | May 10 | May 17 | — | Aug 2 – Nov 15 | 60–80 |
| Bleeding Hearts | Mar 8 | — | May 17 | — | Jul 12 – Aug 16 | 60–90 |
| Calendula | Mar 29 | Apr 12 | May 10 | — | Jun 28 – Sep 27 | 50–70 |
| California Poppy | — | Apr 12 | — | — | Jun 21 – Aug 2 | 60–90 |
| Celosia | Apr 5 | May 17 | May 17 | — | Jul 19 – Nov 1 | 60–90 |
| Columbine | Mar 8 | May 24 | May 24 | — | Jul 19 – Aug 23 | 70–100 |
| Coreopsis | Mar 8 | May 17 | May 17 | — | Jul 26 – Nov 15 | 60–80 |
| Cosmos | Apr 12 | May 10 | May 10 | — | Jul 19 – Oct 25 | 60–90 |
| Crocus | — | — | — | Aug 11 | Jun 30 – Jul 21 | 10–20 |
| Daffodils | — | — | — | Aug 11 | Jul 7 – Jul 28 | 20–40 |
| Dahlias | Apr 12 | May 17 | May 17 | — | Aug 2 – Nov 15 | 70–120 |
| Daylily | Mar 8 | — | May 17 | — | Aug 2 – Nov 15 | 60–90 |
| Dianthus | Mar 15 | Apr 12 | Apr 26 | — | Jun 14 – Sep 13 | 60–80 |
| Echinacea (Purple Coneflower) | Mar 8 | May 24 | May 24 | — | Aug 16 – Nov 22 | 70–90 |
| Foxglove | Mar 8 | May 17 | May 17 | — | Jul 12 – Aug 16 | 80–120 |
| Gaillardia (Blanket Flower) | Mar 22 | May 17 | May 17 | — | Jul 26 – Nov 29 | 70–100 |
| Geraniums | Mar 1 | — | May 17 | — | Jul 26 – Oct 25 | 70–100 |
| Gladiolus | — | May 10 | May 10 | — | Jul 26 – Nov 8 | 70–100 |
| Hostas | Mar 1 | — | May 17 | — | Aug 2 – Nov 15 | 60–90 |
| Hyacinths | — | — | — | Aug 11 | Jul 28 – Aug 18 | 14–28 |
| Hydrangeas | Mar 1 | — | May 17 | — | Jul 26 – Nov 1 | 90–150 |
| Impatiens | Mar 15 | — | May 17 | — | Jul 26 – Nov 1 | 60–75 |
| Irises | — | Division | May 17 | — | Jul 12 – Aug 9 | 60–100 |
| Larkspur | — | Apr 12 | — | — | Jun 21 – Aug 16 | 60–90 |
| Lavender | Mar 1 | — | May 24 | — | Aug 2 – Sep 27 | 90–120 |
| Lilies | — | Division | May 17 | — | Jul 26 – Nov 1 | 70–120 |
| Lobelia | Mar 8 | — | Apr 26 | — | Jun 21 – Sep 13 | 70–80 |
| Lupine | Mar 8 | May 17 | May 17 | — | Jul 12 – Aug 16 | 75–100 |
| Marigolds | Mar 29 | May 17 | May 17 | — | Jul 12 – Oct 11 | 50–70 |
| Nasturtium | Apr 12 | May 17 | May 17 | — | Jul 12 – Nov 1 | 55–65 |
| Pansy | Mar 1 | — | May 10 | Jul 28 | Jul 5 – Sep 6 | 70–90 |
| Peonies | — | Division | May 17 | — | Jul 19 – Aug 23 | 90–120 |
| Petunia | Mar 15 | — | May 17 | — | Jul 26 – Nov 1 | 70–90 |
| Phlox | Mar 8 | May 17 | May 17 | — | Jul 26 – Oct 18 | 80–110 |
| Portulaca | Apr 5 | May 17 | May 17 | — | Jul 5 – Oct 18 | 50–70 |
| Ranunculus | Mar 29 | — | May 10 | — | Jun 21 – Jul 19 | 90–120 |
| Roses | Mar 1 | — | May 17 | — | Jul 26 – Nov 15 | 90–180 |
| Salvia | Mar 8 | — | May 17 | — | Jul 26 – Nov 1 | 70–90 |
| Sedum (Stonecrop) | Mar 8 | — | May 17 | — | Sep 6 – Nov 22 | 60–90 |
| Snapdragon | Mar 1 | Apr 19 | May 10 | — | Jul 19 – Sep 27 | 70–100 |
| Sunflower | Apr 19 | May 17 | May 17 | — | Aug 9 – Nov 1 | 70–100 |
| Sweet Alyssum | Mar 22 | Apr 19 | May 10 | — | Jun 21 – Aug 30 | 45–60 |
| Sweet Pea | Mar 29 | Apr 5 | May 10 | — | Jul 26 – Oct 4 | 65–85 |
| Tulips | — | — | — | Aug 11 | Jul 21 – Aug 18 | 15–30 |
| Vinca (Annual) | Mar 1 | — | May 17 | — | Jul 26 – Nov 1 | 70–90 |
| Yarrow | Mar 8 | May 10 | May 17 | — | Jul 26 – Nov 15 | 60–90 |
| Zinnia | Apr 12 | May 17 | May 17 | — | Jul 26 – Nov 1 | 60–70 |
Monthly Planting Guide for Boundary County
Gardening Guides & Resources
Helpful guides from The Ultimate Homestead to improve your garden in Boundary County.
Frequently Asked Questions
What planting zone is Boundary County, ID?
Boundary County is in USDA Hardiness Zone 6a. 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 Boundary County, ID?
Based on 31 years of NOAA weather station data, the median last spring frost in Boundary County falls around May 10. In 8 out of 10 years, last frost lands between April 22 and June 4 — a 43-day window of variability. Use June 4 as your conservative safe-to-plant date for frost-sensitive crops.
When is the first fall frost in Boundary County, ID?
The median first fall frost in Boundary County arrives around September 22. In cold years it can arrive as early as September 1; in mild years as late as October 14. Harvest or protect frost-sensitive crops — tomatoes, peppers, basil, squash — before this date.
How long is the growing season in Boundary County?
Boundary County has a frost-free growing season of approximately 135 days. Focus on short-season varieties and start warm-season crops indoors 6–8 weeks before last frost. Climate records show the growing season is trending longer by about 3.05 days per decade.
What is the soil like in Boundary County for gardening?
Boundary County has predominantly Loam soil with a pH range of 6.7–8.3 and Well Drained drainage. Most vegetables and herbs grow well with standard composting and seasonal soil amendment.
What is grown commercially in Boundary County?
Boundary County has commercial agriculture that includes Hay, Potatoes, Wheat, 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 Boundary County a good location for home gardening?
Boundary County scores 36/100 (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.
Your Boundary County Garden Planner — Free
A 22-page printable planner built for Boundary County (Zone 6a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.
The Gardener's Encyclopedia to Companion Planting
The pairings that make vegetables, herbs, and flowers grow better — and the ones that quietly wreck a bed.
- Proven pairings for 200+ vegetables, herbs, flowers, and fruits
- Full seed-starting + planting schedule with timing and spacing
- Bonus: square-foot gardening guide + printable seasonal planners
Seed Saving & Storage Guide
Most saved seeds go bad before next season. This shows exactly when to pick, how to dry, and where to store seeds from 200 plants so yours don't.
- 200 plants, step-by-step: life cycle, pollination type, isolation
- Exact temperature + humidity ranges that keep seeds viable
- Bonus: searchable Google Sheets tracker + custom GPT assistant
Composting Guide for Homesteaders
Turn kitchen scraps and yard waste into compost that actually feeds the garden — instead of a pile that smells, attracts pests, and never breaks down.
- 14 sections on composting methods, soil science, and troubleshooting
- The 7-step hot-compost system from start to finish
- Bonus tools: troubleshooting chart, safety guide, monitoring log