Clark County, ID — Planting Guide
Clark County, Idaho gardeners: here's your May plan
We've pulled the most time-sensitive tasks for Clark County, Idaho this May and put them front and centre. Tackle them in order.
-
Move angelica, anise, and borage into the garden
Your last frost (June 7) has passed. These warm-season crops can handle outdoor soil now.
-
Plant carrots, kale, and lettuce from seed, right in the garden
These tolerate cool soil, so you're not gambling by sowing now.
June prep starts now
- Transplants going out: basil, cucumber, and kale
- Direct-sowing: basil, cucumber, and green beans
- First harvests: radish, cress, and microgreens
Clark County is in USDA Zone 5b. The average last spring frost is June 7 and the first fall frost is September 10, giving you a growing season of approximately 95 days.
At an elevation of 7,493 ft, Clark County receives approximately 21.9 in of rainfall annually. Summer highs average 82°F with winter lows around 3°F. The predominant soil type is Loam.
Based on 31 years of NOAA climate station data, the last frost date here varies by 44 days year to year — ranging from May 8 in warm years to June 21 in cold years. The growing season is trending longer by about 8.39 days per decade. Clark County scores 34/100 (Challenging) on the Microclimate Index.
🌡️ Zone
5b (°F to °F min)
❄️ Last Frost
June 7
🍂 First Frost
September 10
📅 Growing Season
95 days
⛰️ Elevation
7,493 ft
🌧️ Annual Rainfall
21.9 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 | 1.7 in | 6 days | — | None |
| Feb | 1.4 in | 5 days | — | None |
| Mar | 1.8 in | 9 days | — | None |
| Apr | 2.5 in | 7 days | 1.8 in | High |
| May | 2.5 in | 7 days | 1.8 in | High |
| Jun | 1.5 in | 4 days | 2.8 in | High |
| Jul | 1.7 in | 5 days | 2.6 in | High |
| Aug | 2.2 in | 6 days | 2.1 in | High |
| Sep | 1.7 in | 6 days | 2.6 in | High |
| Oct | 1.8 in | 6 days | 2.5 in | High |
| Nov | 1.6 in | 5 days | — | None |
| Dec | 1.3 in | 6 days | — | None |
Annual total: 21.7 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.
Clark County Soil Profile
Soil Type
Loam
Soil pH
6.8-7.8
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 21 | Oct 4 | 105 days |
| Cautious | Jun 17 | Sep 21 | 96 days |
| Average year | Jun 7 | Sep 10 | 95 days |
| Optimistic | May 23 | Sep 6 | 106 days |
| Aggressive (risky) | May 8 | Aug 22 | 106 days |
Not very — frost dates can vary by ±44 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 8.4 days per decade). Spring is arriving earlier than it used to. Good news for gardeners.
Gardening Difficulty Score
Clark County has challenging growing conditions. Season extension and careful variety selection are essential.
Local Gardening Help in Clark 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 Clark County's climate and soil.
County Extension Office
Clark 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 Clark County
Finding local nurseries & garden centers in Clark County
Why Buy Local
Local nurseries carry plants that are proven to grow in your area. Staff can give you advice specific to Clark 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 Clark County ID" or "garden center Clark 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 Clark County ID" or check your extension office and local parks department. Facebook groups like "Clark 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.
Sunlight & Day Length
Monthly daylight hours and peak sun — critical for onion varieties, photoperiod-sensitive plants, and solar garden planning.
Longest Day
15.3 hours
Summer solstice daylight
Shortest Day
8.7 hours
Winter solstice daylight
Peak Sun Hours
11.5 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 | 9 hr | 5.2 hr | Short day |
| February | 10.2 hr | 5.8 hr | Short day |
| March | 11.6 hr | 7.2 hr | Short day |
| April | 13.2 hr | 7.5 hr | Neutral |
| May | 14.6 hr | 8.9 hr | Long day |
| June | 15.3 hr | 11.5 hr | Long day |
| July | 15 hr | 10.9 hr | Long day |
| August | 13.8 hr | 9.3 hr | Neutral |
| September | 12.3 hr | 8.6 hr | Neutral |
| October | 10.7 hr | 6.7 hr | Short day |
| November | 9.4 hr | 5.5 hr | Short day |
| December | 8.7 hr | 4.8 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
Aug
Microbial activity peaks when soil is warm.
Active Composting
1 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 | -7°F | 0°F | ❄️ Dormant | ~36 weeks |
| Feb | -5°F | -0°F | ❄️ Dormant | ~36 weeks |
| Mar | 3°F | 8°F | ❄️ Dormant | ~36 weeks |
| Apr | 20°F | 17°F | ❄️ Dormant | ~36 weeks |
| May | 32°F | 27°F | ❄️ Dormant | ~36 weeks |
| Jun | 42°F | 37°F | 🐢 Slow | ~24 weeks |
| Jul | 49°F | 43°F | 🐢 Slow | ~24 weeks |
| Aug | 51°F | 46°F | ♻️ Active | ~14 weeks |
| Sep | 43°F | 43°F | 🐢 Slow | ~24 weeks |
| Oct | 29°F | 34°F | ❄️ Dormant | ~36 weeks |
| Nov | 15°F | 19°F | ❄️ Dormant | ~36 weeks |
| Dec | 1°F | 8°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 Clark 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 5 common pests in your area
| Pest | Risk Level | Peak Months |
|---|---|---|
| Aphids | Moderate | May, Jun, Jul, Aug |
| Cabbage worms | Low | Jun, Jul, Aug |
| Colorado potato beetle | Low | Jun, Jul |
| Flea beetles | Moderate | May, Jun, Jul |
| Slugs | Moderate | May, Jun, Jul, Aug, Sep |
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 Clark County
Cover crops protect bare soil, fix nitrogen, suppress weeds, and improve soil structure — with county-specific planting dates.
Spring Cover Crops (2 options) — Build soil before the main growing season
| Crop | Plant By | Terminate | N-Fixing | Soil Benefit |
|---|---|---|---|---|
| Buckwheat | Jun 14 | Jul 9 | — | Rapid growth, attracts pollinators, suppresses weeds |
| White clover | May 12 | Jul 9 | ✓ 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 | Jun 30 | Aug 13 | — | Deep roots break compaction, attract pollinators and beneficial insects |
Fall Cover Crops (5 options) — Plant after harvest to protect soil over winter
| Crop | Plant By | Terminate | N-Fixing | Soil Benefit |
|---|---|---|---|---|
| Daikon radish | Jul 16 | May 24 | — | Deep taproot breaks compaction, excellent for clay soils |
| Hairy vetch | Jun 22 | May 17 | ✓ Yes | Excellent nitrogen fixer, good for depleted soils |
| Oats | Aug 13 | May 24 | — | Quick biomass, winterkills in cold zones — no spring tillage needed |
| Winter rye | Jun 10 | May 24 | — | Suppresses weeds, prevents erosion, breaks up compacted soil |
| Winter wheat | Jun 12 | May 24 | — | 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: 16 mph Summer: 11 mph
Fall: 13 mph Winter: 15 mph
Prevailing wind: W. Windy area — plant a windbreak hedge on the W side of your garden.
Windbreak Benefit
6.8/10
Moderately beneficial — a simple fence or trellis can protect delicate crops from wind stress.
Frost Pocket Risk
High
Hilly terrain with 2,942 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
10,815 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, Aug
Highest rainfall months — your barrels will fill up quickly during these months.
Months to Draw From Storage
Feb, Jun, 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 21.7 inches of rain per year
- A 1,000 sq ft roof can collect roughly 10,815 gallons annually
- Rainwater harvesting is fully legal in your state
- Stock up on stored water before your dry season (Feb, Jun, Dec)
- Use a first-flush diverter to keep roof debris out of your collection
Soil & Growing Conditions in Clark County
Soil Type
Loam
Soil pH 6.8–7.8 · Moderately Well Drained drainage
Good candidate for raised beds to maximise drainage and extend the season.
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
95-day frost-free season
A short season means indoor starts are critical for warm-season crops. Prioritise cold-hardy, fast-maturing varieties and use row covers to extend autumn harvests.
Your Free Printable Garden Planner
Plan every bed, every planting, every harvest — in one place. This 24-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 Clark County
106 vegetables that grow well in Zone 5b with planting dates for Clark County.
Show all 106 vegetables with planting dates
| Plant | Start Indoors | Direct Sow | Transplant | Harvest | Days to Maturity |
|---|---|---|---|---|---|
| Acorn Squash | May 3 | Jun 14 | Jun 21 | Sep 13 – Oct 18 | 80–100 |
| Amaranth | Apr 12 | Jun 14 | Jun 21 | Sep 20 – Nov 8 | 90–120 |
| Arugula | May 3 | May 24 | Jun 7 | Jul 12 – Sep 13 | 30–50 |
| Asparagus | — | — | Jun 21 | — | 730–1095 |
| Beets | — | May 24 | — | Jul 19 – Aug 16 | 50–70 |
| Belgian Endive | May 3 | May 24 | Jun 7 | Sep 27 – Nov 22 | 110–150 |
| Bitter Melon | Apr 12 | Jun 14 | Jun 21 | Aug 23 – Oct 4 | 60–90 |
| Black Beans | — | Jun 14 | — | Sep 13 – Nov 1 | 90–120 |
| Bok Choy | May 3 | May 24 | Jun 7 | Jul 19 – Aug 23 | 40–60 |
| Broccoli | May 3 | May 24 | Jun 7 | Aug 9 – Sep 20 | 60–90 |
| Broccoli Rabe | May 3 | May 24 | Jun 7 | Jul 19 – Aug 23 | 40–60 |
| Brussels Sprouts | May 3 | May 24 | Jun 7 | Sep 6 – Nov 1 | 90–130 |
| Butternut Squash | May 3 | Jun 14 | Jun 21 | Sep 20 – Oct 25 | 85–110 |
| Cabbage | May 3 | May 24 | Jun 7 | Aug 9 – Oct 4 | 60–100 |
| Calabash | Apr 12 | Jun 14 | Jun 21 | Sep 13 – Nov 8 | 80–120 |
| Carrots | — | May 24 | — | Jul 26 – Aug 30 | 60–80 |
| Cauliflower | May 3 | May 24 | Jun 7 | Aug 2 – Oct 4 | 55–100 |
| Celeriac | May 3 | May 24 | Jun 7 | Sep 20 – Oct 25 | 100–120 |
| Celery | May 3 | May 24 | Jun 7 | Aug 30 – Oct 25 | 80–120 |
| Celtuce | May 3 | May 24 | Jun 7 | Aug 9 – Sep 20 | 60–90 |
| Chard | May 3 | May 24 | Jun 7 | Aug 2 – Sep 20 | 50–60 |
| Chickpeas | May 3 | May 24 | Jun 7 | Aug 30 – Oct 11 | 80–110 |
| Chicory | May 3 | May 24 | Jun 7 | Aug 9 – Sep 20 | 60–85 |
| Chinese Cabbage | May 3 | May 24 | Jun 7 | Aug 2 – Aug 30 | 50–70 |
| Christmas Lima Beans | Apr 12 | Jun 14 | Jun 21 | Sep 13 – Oct 18 | 80–100 |
| Collard Greens | May 3 | May 24 | Jun 7 | Aug 2 – Oct 4 | 55–75 |
| Corn | — | Jun 14 | — | Aug 16 – Oct 11 | 60–100 |
| Cowpeas | — | Jun 14 | — | Aug 16 – Sep 27 | 60–90 |
| Cress | May 3 | May 24 | Jun 7 | Jun 21 – Jul 12 | 14–21 |
| Crookneck Squash | May 3 | Jun 14 | Jun 21 | Aug 9 – Sep 6 | 45–60 |
| Crosne | — | May 24 | — | Oct 25 – Nov 8 | 150–200 |
| Cucumber | May 3 | Jun 14 | Jun 21 | Aug 16 – Oct 11 | 50–70 |
| Daikon | — | May 24 | — | Jul 19 – Aug 16 | 50–70 |
| Delicata Squash | May 3 | Jun 14 | Jun 21 | Sep 13 – Oct 18 | 80–100 |
| Edamame | — | Jun 14 | — | Aug 30 – Oct 11 | 75–100 |
| Eggplant | Mar 29 | Jun 14 | Jun 21 | Aug 30 – Nov 1 | 65–85 |
| Endive | May 3 | May 24 | Jun 7 | Jul 26 – Aug 30 | 45–65 |
| Escarole | May 3 | May 24 | Jun 7 | Aug 2 – Aug 30 | 50–70 |
| Fava Beans | May 3 | May 24 | Jun 7 | Aug 23 – Oct 4 | 75–100 |
| Fennel | Apr 12 | Jun 14 | Jun 21 | Aug 23 – Oct 4 | 60–90 |
| Garlic | — | — | — | — | 90–240 |
| Green Beans | — | Jun 14 | — | Aug 9 – Oct 4 | 50–65 |
| Horseradish | — | — | Jun 21 | Oct 25 – Dec 6 | 120–180 |
| Hot Peppers | Mar 29 | Jun 14 | Jun 21 | Aug 30 – Dec 6 | 70–120 |
| Hubbard Squash | May 3 | Jun 14 | Jun 21 | Oct 4 – Nov 8 | 100–120 |
| Kabocha | May 3 | Jun 14 | Jun 21 | Sep 20 – Oct 18 | 85–100 |
| Kai Lan | May 3 | May 24 | Jun 7 | Jul 26 – Aug 23 | 45–60 |
| Kale | May 3 | May 24 | Jun 7 | Aug 2 – Sep 27 | 50–70 |
| Kidney Beans | — | Jun 14 | — | Sep 13 – Oct 18 | 85–110 |
| Kohlrabi | May 3 | May 24 | Jun 7 | Jul 26 – Aug 30 | 45–65 |
| Komatsuna | May 3 | May 24 | Jun 7 | Jul 12 – Aug 16 | 35–50 |
| Leeks | May 3 | May 24 | Jun 7 | Sep 6 – Nov 22 | 90–150 |
| Lentils | May 3 | May 24 | Jun 7 | Aug 30 – Oct 11 | 80–110 |
| Lettuce | May 3 | May 24 | Jun 7 | Jul 12 – Sep 20 | 30–60 |
| Lima Beans | — | Jun 14 | — | Aug 16 – Sep 27 | 60–90 |
| Mache | May 3 | May 24 | Jun 7 | Jul 19 – Aug 23 | 40–60 |
| Melon | May 3 | Jun 14 | Jun 21 | Aug 30 – Oct 18 | 70–100 |
| Microgreens | May 3 | May 24 | Jun 7 | Jun 14 – Jul 12 | 7–21 |
| Mitsuba | May 3 | May 24 | May 31 | Jul 26 – Sep 20 | 50–70 |
| Mizuna | May 3 | May 24 | Jun 7 | Jul 12 – Aug 9 | 30–45 |
| Mustard Greens | May 3 | May 24 | Jun 7 | Jul 12 – Sep 13 | 30–50 |
| Napa Cabbage | May 3 | May 24 | Jun 7 | Aug 2 – Sep 6 | 55–75 |
| New Zealand Spinach | Apr 12 | Jun 14 | Jun 21 | Aug 16 – Sep 13 | 55–70 |
| Okra | Apr 12 | Jun 14 | Jun 21 | Aug 16 – Oct 11 | 50–65 |
| Onion | May 3 | May 24 | Jun 7 | Sep 6 – Oct 25 | 90–120 |
| Pac Choi | May 3 | May 24 | Jun 7 | Jul 19 – Aug 16 | 40–55 |
| Parsnip | — | May 24 | — | Sep 6 – Oct 18 | 100–130 |
| Patty Pan Squash | May 3 | Jun 14 | Jun 21 | Aug 9 – Sep 6 | 45–60 |
| Peas | May 3 | May 24 | Jun 7 | Aug 2 – Sep 27 | 55–70 |
| Peppers | Mar 29 | Jun 14 | Jun 21 | Aug 23 – Nov 1 | 60–90 |
| Pole Beans | Apr 12 | Jun 14 | Jun 21 | Aug 16 – Oct 11 | 55–70 |
| Potatoes | Apr 12 | Jun 14 | Jun 21 | Aug 30 – Nov 8 | 70–120 |
| Pumpkin | May 3 | Jun 14 | Jun 21 | Sep 20 – Nov 8 | 85–120 |
| Purslane | May 3 | May 24 | Jun 7 | Jul 19 – Aug 23 | 40–60 |
| Radicchio | May 3 | May 24 | Jun 7 | Aug 9 – Sep 13 | 60–80 |
| Radish | — | May 24 | — | Jun 21 – Jul 12 | 22–35 |
| Rhubarb | — | — | Jun 28 | — | 365–730 |
| Romanesco | May 3 | May 24 | Jun 7 | Aug 23 – Oct 4 | 75–100 |
| Rutabaga | — | May 24 | — | Aug 16 – Sep 20 | 80–100 |
| Salsify | — | May 24 | — | Sep 6 – Oct 18 | 100–130 |
| Savoy Cabbage | May 3 | May 24 | Jun 7 | Aug 16 – Oct 11 | 70–110 |
| Scallions | May 3 | May 24 | Jun 7 | Aug 2 – Aug 30 | 50–70 |
| Scarlet Runner Beans | Apr 12 | Jun 14 | Jun 21 | Aug 23 – Sep 27 | 60–80 |
| Shallot | May 3 | May 24 | Jun 7 | Sep 6 – Oct 25 | 90–120 |
| Shiso | Apr 19 | Jun 14 | Jun 21 | Aug 16 – Oct 11 | 50–70 |
| Snap Peas | Apr 12 | Jun 14 | Jun 21 | Aug 16 – Oct 11 | 55–70 |
| Snow Peas | May 3 | May 24 | Jun 7 | Aug 2 – Sep 27 | 50–65 |
| Soybeans | — | Jun 14 | — | Sep 6 – Nov 1 | 80–120 |
| Spaghetti Squash | May 3 | Jun 14 | Jun 21 | Sep 20 – Oct 18 | 85–100 |
| Spinach | May 3 | May 24 | Jun 7 | Jul 12 – Sep 13 | 35–50 |
| Squash (Summer) | May 3 | Jun 14 | Jun 21 | Aug 9 – Oct 11 | 45–65 |
| Squash (Winter) | May 3 | Jun 14 | Jun 21 | Sep 13 – Nov 8 | 80–120 |
| Sunchoke | — | — | Jun 21 | Oct 11 – Dec 6 | 110–150 |
| Sunflower | Apr 12 | Jun 14 | Jun 21 | Aug 30 – Oct 18 | 70–100 |
| Sweet Corn | — | Jun 14 | — | Aug 16 – Sep 27 | 60–90 |
| Sweet Potatoes | Apr 12 | Jun 14 | Jun 21 | Sep 20 – Nov 8 | 90–120 |
| Tatsoi | May 3 | May 24 | Jun 7 | Jul 12 – Aug 16 | 35–50 |
| Tomatillo | Apr 12 | Jun 14 | Jun 21 | Aug 23 – Nov 1 | 60–85 |
| Tomatoes | Apr 12 | Jun 14 | Jun 21 | Aug 23 – Nov 1 | 60–85 |
| Turnip | — | May 24 | — | Jul 5 – Aug 9 | 40–60 |
| Watercress | May 3 | May 24 | Jun 7 | Jul 19 – Aug 23 | 40–60 |
| Watermelon | May 3 | Jun 14 | Jun 21 | Aug 30 – Oct 18 | 70–100 |
| Wax Beans | — | Jun 14 | — | Aug 9 – Oct 4 | 50–65 |
| Winter Melon | Apr 12 | Jun 14 | Jun 21 | Sep 20 – Nov 8 | 90–120 |
| Yard Long Beans | Apr 12 | Jun 14 | Jun 21 | Aug 16 – Sep 27 | 55–80 |
| Zucchini | May 3 | Jun 14 | Jun 21 | Aug 9 – Oct 4 | 45–60 |
🍓 Fruits to Grow in Clark County
27 fruits that grow well in Zone 5b with planting dates for Clark County.
Show all 27 fruits with planting dates
| Plant | Start Indoors | Direct Sow | Transplant | Harvest | Days to Maturity |
|---|---|---|---|---|---|
| Alpine Strawberries | — | — | Jun 28 | Sep 27 – Dec 13 | 90–180 |
| Aronia | — | — | Jun 28 | — | 730–1095 |
| Blackberries | — | — | Jun 28 | — | 365–730 |
| Blueberries | — | — | Jun 28 | — | 730–1095 |
| Boysenberries | — | — | Jun 28 | — | 365–730 |
| Cantaloupe | — | — | Jun 28 | Sep 6 – Oct 11 | 70–90 |
| Che Fruit | — | — | Jun 28 | — | 1095–1825 |
| Cranberries | — | — | Jun 28 | — | 730–1095 |
| Currants | — | — | Jun 28 | — | 730–1095 |
| Elderberries | — | — | Jun 28 | — | 730–1095 |
| Goji Berries | — | — | Jun 28 | — | 730–1095 |
| Gooseberries | — | — | Jun 28 | — | 730–1095 |
| Grapes | — | — | Jun 28 | — | 730–1095 |
| Ground Cherry | — | — | Jun 28 | Sep 6 – Nov 1 | 65–80 |
| Hardy Kiwi | — | — | Jun 28 | — | 1095–1825 |
| Haskaps | — | — | Jun 28 | — | 730–1095 |
| Honeydew | — | — | Jun 28 | Sep 20 – Nov 1 | 80–110 |
| Jostaberry | — | — | Jun 28 | — | 730–1095 |
| Lingonberries | — | — | Jun 28 | — | 730–1095 |
| Medlar | — | — | Jun 28 | — | 1095–1825 |
| Mulberries | — | — | Jun 28 | — | 730–1825 |
| Pawpaw | — | — | Jun 28 | — | 1095–2555 |
| Persimmon | — | — | Jun 28 | — | 1095–2555 |
| Quince | — | — | Jun 28 | — | 1095–1825 |
| Raspberries | — | — | Jun 28 | — | 365–730 |
| Serviceberries | — | — | Jun 28 | — | 730–1095 |
| Strawberries | — | — | Jun 28 | Sep 27 – Dec 13 | 90–365 |
🌿 Herbs to Grow in Clark County
37 herbs that grow well in Zone 5b with planting dates for Clark County.
Show all 37 herbs with planting dates
| Plant | Start Indoors | Direct Sow | Transplant | Harvest | Days to Maturity |
|---|---|---|---|---|---|
| Angelica | May 3 | May 24 | May 31 | — | 365–730 |
| Anise | May 3 | May 24 | May 31 | Aug 30 – Nov 15 | 90–120 |
| Basil | Apr 19 | Jun 14 | Jun 21 | Aug 16 – Oct 18 | 50–75 |
| Bee Balm | — | — | Jun 14 | Sep 13 – Nov 29 | 90–120 |
| Borage | May 3 | May 24 | May 31 | Jul 26 – Sep 13 | 50–60 |
| Caraway | May 3 | May 24 | May 31 | — | 365–450 |
| Catnip | — | — | Jun 14 | Aug 16 – Oct 18 | 60–80 |
| Chamomile | May 3 | May 24 | May 31 | Aug 2 – Oct 11 | 60–90 |
| Chervil | May 3 | May 24 | May 31 | Jul 12 – Sep 13 | 40–60 |
| Chives | — | — | Jun 14 | Aug 16 – Oct 25 | 60–90 |
| Cilantro | May 3 | May 24 | May 31 | Jul 12 – Sep 13 | 40–60 |
| Comfrey | — | — | Jun 14 | Aug 16 – Oct 25 | 60–90 |
| Cumin | May 3 | May 24 | May 31 | Sep 13 – Nov 15 | 100–120 |
| Dill | May 3 | May 24 | May 31 | Jul 12 – Sep 13 | 40–60 |
| Echinacea | — | — | Jun 14 | Oct 18 – Nov 29 | 120–180 |
| Epazote | Apr 19 | Jun 14 | Jun 21 | Aug 9 – Oct 4 | 45–60 |
| Fennel (herb) | May 3 | May 24 | May 31 | Aug 2 – Oct 11 | 60–90 |
| Feverfew | — | — | Jun 14 | Sep 13 – Nov 29 | 90–120 |
| Garlic Chives | — | — | Jun 14 | Aug 16 – Oct 25 | 60–90 |
| Horehound | — | — | Jun 14 | Aug 30 – Oct 25 | 75–90 |
| Hyssop | — | — | Jun 14 | Aug 23 – Oct 25 | 70–90 |
| Lavender | — | — | Jun 14 | Sep 13 – Nov 29 | 90–200 |
| Lemon Balm | — | — | Jun 14 | Aug 16 – Oct 4 | 60–70 |
| Lemon Thyme | — | — | Jun 14 | Aug 23 – Oct 25 | 70–90 |
| Lovage | — | — | Jun 14 | Aug 23 – Oct 25 | 70–90 |
| Mint | — | — | Jun 14 | Aug 16 – Oct 25 | 60–90 |
| Oregano | — | — | Jun 14 | Aug 16 – Oct 25 | 60–90 |
| Parsley | May 3 | May 24 | May 31 | Aug 2 – Oct 4 | 60–80 |
| Rue | — | — | Jun 14 | Aug 23 – Oct 25 | 70–90 |
| Sage | — | — | Jun 14 | Aug 30 – Oct 25 | 75–90 |
| Savory | — | — | Jun 14 | Aug 9 – Oct 4 | 50–70 |
| Sorrel | May 3 | May 24 | May 31 | Jul 12 – Sep 13 | 40–60 |
| Tarragon | — | — | Jun 14 | Aug 16 – Oct 25 | 60–90 |
| Thai Basil | Apr 19 | Jun 14 | Jun 21 | Aug 16 – Oct 18 | 50–75 |
| Thyme | — | — | Jun 14 | Aug 23 – Oct 25 | 70–90 |
| Valerian | — | — | Jun 14 | Oct 18 – Nov 29 | 120–180 |
| Yarrow | — | — | Jun 14 | Sep 13 – Nov 29 | 90–120 |
Monthly Planting Guide for Clark County
Gardening Guides & Resources
Helpful guides from The Ultimate Homestead to improve your garden in Clark County.
Frequently Asked Questions
What planting zone is Clark County, ID?
Clark 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 Clark County, ID?
Based on 31 years of NOAA weather station data, the median last spring frost in Clark County falls around June 7. In 8 out of 10 years, last frost lands between May 8 and June 21 — a 44-day window of variability. Use June 21 as your conservative safe-to-plant date for frost-sensitive crops.
When is the first fall frost in Clark County, ID?
The median first fall frost in Clark County arrives around September 10. In cold years it can arrive as early as August 22; in mild years as late as October 4. Harvest or protect frost-sensitive crops — tomatoes, peppers, basil, squash — before this date.
How long is the growing season in Clark County?
Clark County has a frost-free growing season of approximately 95 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 8.39 days per decade.
What is the soil like in Clark County for gardening?
Clark County has predominantly Loam soil with a pH range of 6.8–7.8 and Moderately Well Drained drainage. Most vegetables and herbs grow well with standard composting and seasonal soil amendment.
What is grown commercially in Clark County?
Clark County has commercial agriculture that includes Hay, Potatoes, Wheat, Dairy, Barley. These crops reflect the local climate and soil conditions — what succeeds commercially often translates well to home gardens in the same area.
Is Clark County a good location for home gardening?
Clark County scores 34/100 (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 Clark County Garden Planner — Free
A 24-page printable planner built for Clark County (Zone 5b). 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