Jefferson County, WA — Planting Guide
Top priorities for Jefferson County, Washington gardeners in June
Each item below is timed to Jefferson County, Washington's frost dates and soil temperatures. Skip nothing, stress about nothing.
-
Fire up the seed-starting tray: basil, peppers, and pole beans
Bottom-water once the first true leaves appear — it keeps stems dry and knocks back damping-off.
-
Pick basil, carrots, and cucumber
Check every 1–2 days. Many of these get tough or go to seed if you wait too long.
July prep starts now
- First harvests: basil, carrots, and cucumber
Jefferson County is in USDA Zone 8b. The average last spring frost is April 14 and the first fall frost is October 29, giving you a growing season of approximately 198 days.
At an elevation of 205 ft, Jefferson County receives approximately 40.7 in of rainfall annually. Summer highs average 88°F with winter lows around 44°F. The predominant soil type is Silt Loam.
Based on 31 years of NOAA climate station data, the last frost date here varies by 47 days year to year — ranging from March 23 in warm years to May 9 in cold years. Jefferson County scores 76/100 (Good) on the Microclimate Index.
🌡️ Zone
8b (15°F to 20°F min)
❄️ Last Frost
April 14
🍂 First Frost
October 29
📅 Growing Season
198 days
⛰️ Elevation
205 ft
🌧️ Annual Rainfall
40.7 in
Monthly Watering Calendar for Jefferson County
When you'll need to water your garden — based on average monthly rainfall vs. the ~1 inch/week most gardens need.
Quick context: The 1-inch-per-week rule applies to most vegetable crops. Jefferson County averages 41" a year — divide by 52 and compare to that 1" target. Some months are above, some below; that's where the calendar earns its keep.
View detailed monthly data
| Month | Avg Rainfall | Rainy Days | Extra Water Needed | Watering Effort |
|---|---|---|---|---|
| Jan | 6.4 in | 20 days | — | None |
| Feb | 4.7 in | 17 days | — | Low |
| Mar | 3.9 in | 15 days | 0.4 in | Low |
| Apr | 2.6 in | 11 days | 1.7 in | High |
| May | 2.1 in | 9 days | 2.2 in | High |
| Jun | 1.5 in | 7 days | 2.8 in | High |
| Jul | 0.5 in | 2 days | 3.8 in | Critical |
| Aug | 0.6 in | 3 days | 3.7 in | Critical |
| Sep | 1.6 in | 4 days | 2.7 in | High |
| Oct | 3.5 in | 9 days | 0.8 in | Moderate |
| Nov | 6.3 in | 18 days | — | Low |
| Dec | 7.1 in | 19 days | — | None |
Annual total: 40.8 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.
Jefferson County Soil Profile
Soil Type
Silt Loam
Soil pH
5.7-6.8
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) | May 9 | Nov 19 | 194 days |
| Cautious | Apr 28 | Nov 6 | 192 days |
| Average year | Apr 14 | Oct 29 | 198 days |
| Optimistic | Apr 6 | Oct 23 | 200 days |
| Aggressive (risky) | Mar 23 | Oct 11 | 202 days |
Not very — frost dates can vary by ±47 days year-to-year. Use the "Conservative" row in the table below, and keep row covers handy for surprise late frosts.
Gardening Difficulty Score
Jefferson County offers good growing conditions. A little planning around frost dates goes a long way.
Local Gardening Help in Jefferson 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 Jefferson County's climate and soil.
County Extension Office
Jefferson County Washington State University Extension Extension Office
Phone: 509-335-2811
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 Jefferson County
Finding local nurseries & garden centers in Jefferson County
Why Buy Local
Local nurseries carry plants that are proven to grow in your area. Staff can give you advice specific to Jefferson 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 Jefferson County WA" or "garden center Jefferson 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 Jefferson County WA" or check your extension office and local parks department. Facebook groups like "Jefferson County Gardeners" or "Washington 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 Jefferson County
Monthly daylight hours and peak sun — critical for onion varieties, photoperiod-sensitive plants, and solar garden planning.
For new gardeners: The longest day at Jefferson County's latitude gets longer the further north you go. Strawberries, garlic, onions all care. The shortest day gets shorter — which limits winter growing for greens without artificial light.
Longest Day
15.8 hours
Summer solstice daylight
Shortest Day
8.2 hours
Winter solstice daylight
Peak Sun Hours
10.4 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 | 2.2 hr | Short day |
| February | 10 hr | 3.1 hr | Short day |
| March | 11.6 hr | 4.2 hr | Short day |
| April | 13.4 hr | 5.9 hr | Neutral |
| May | 14.9 hr | 7.4 hr | Long day |
| June | 15.8 hr | 8.6 hr | Long day |
| July | 15.4 hr | 10.4 hr | Long day |
| August | 14.1 hr | 9.3 hr | Long day |
| September | 12.3 hr | 6.9 hr | Neutral |
| October | 10.6 hr | 4 hr | Short day |
| November | 9 hr | 2.2 hr | Short day |
| December | 8.2 hr | 1.8 hr | Short day |
Peak sun hours factor in typical cloud cover — use these for solar panel and shade-planning calculations.
Soil Temperature & Composting in Jefferson County
Monthly soil temps tell you when to plant warm-season crops, and when your compost pile is actively working.
The practical takeaway: Air temperature lies. Your air can be 70°F in April but the soil 4 inches down is still 50°F — too cold for tomatoes or peppers to root properly. Jefferson County's soil temperature curve tells you the real planting window. A $5 soil thermometer pays for itself in one season.
Plant Warm Crops When
Soil reaches 60°F+
Soil warm enough from May through Oct.
Best Month to Compost
May
Microbial activity peaks when soil is warm.
Active Composting
10 months
Nearly year-round composting.
View detailed monthly data
| Month | Soil 4" Deep | Soil 8" Deep | Compost Activity | Time to Finish |
|---|---|---|---|---|
| Jan | 45°F | 51°F | 🐢 Slow | ~24 weeks |
| Feb | 45°F | 51°F | 🐢 Slow | ~24 weeks |
| Mar | 51°F | 53°F | ♻️ Active | ~14 weeks |
| Apr | 59°F | 59°F | ♻️ Active | ~14 weeks |
| May | 69°F | 68°F | 🔥 Peak | ~8 weeks |
| Jun | 80°F | 77°F | 🔥 Peak | ~8 weeks |
| Jul | 86°F | 82°F | 🔥 Peak | ~8 weeks |
| Aug | 88°F | 87°F | 🔥 Peak | ~8 weeks |
| Sep | 84°F | 81°F | 🔥 Peak | ~8 weeks |
| Oct | 73°F | 73°F | 🔥 Peak | ~8 weeks |
| Nov | 60°F | 66°F | ♻️ Active | ~14 weeks |
| Dec | 50°F | 56°F | ♻️ Active | ~14 weeks |
Highlighted rows = soil 60°F+ (safe for warm-season transplants). Compost finishes fastest during peak activity months.
Pest & Disease Pressure in Jefferson County
Computed from local climate patterns — warmer, humid conditions increase pest generations and fungal disease risk.
For new gardeners: Pest pressure scales with warmth and humidity. Hot humid Jefferson County sees year-round bugs and fungal disease; cold dry regions see almost none. A high pest score means crop rotation, resistant varieties, and a weekly pest-watch routine from day one.
Insect Pest Pressure
High — expect multiple pest generations. Preventative measures essential.
Disease Risk
High fungal/bacterial risk. Space plants for airflow, water at soil level.
Seasonal Risk
View 6 common pests in your area
| Pest | Risk Level | Peak Months |
|---|---|---|
| Aphids | High | Mar, Apr, May, Jun, Jul, Aug, Sep, Oct, Nov |
| Squash vine borers | High | May, Jun, Jul |
| Stink bugs | High | Apr, May, Jun, Jul, Aug, Sep, Oct |
| Whiteflies | Moderate | May, Jun, Jul, Aug, Sep, Oct |
| Spider mites | Moderate | Jun, Jul, Aug, Sep |
| Fire ants | Low | Mar, Apr, May, Jun, Jul, Aug, Sep, Oct |
Organic pest management tips
- Install physical barriers: floating row covers, copper tape for slugs, mesh netting
- Apply Bt (Bacillus thuringiensis) for caterpillar control — safe for beneficial insects
- Use kaolin clay spray to deter a wide range of insects on fruiting crops
- Release beneficial insects: ladybugs for aphids, parasitic wasps for caterpillars
- Apply neem oil weekly during high-pressure months
- Mulch heavily (3-4 inches) to reduce soil-borne disease splash
Cover Crops for Jefferson County
Cover crops protect bare soil, fix nitrogen, suppress weeds, and improve soil structure — with planting dates calibrated for your area.
The practical takeaway: Why not just leave bare soil? Weed seeds, erosion, nutrient leaching, and crust formation. A cover crop solves all of these for the cost of seeds and one mowing.
Spring Cover Crops (4 options) — Build soil before the main growing season
| Crop | Plant By | Terminate | N-Fixing | Soil Benefit |
|---|---|---|---|---|
| Buckwheat | Apr 21 | Aug 20 | — | Rapid growth, attracts pollinators, suppresses weeds |
| Cowpeas (southern peas) | Apr 16 | Aug 20 | ✓ Yes | Excellent nitrogen fixer for warm climates, edible |
| Sorghum-sudan grass | Apr 15 | Aug 20 | — | Massive biomass, breaks compaction, suppresses nematodes |
| White clover | Mar 18 | Sep 3 | ✓ 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 1 | Oct 8 | — | Deep roots break compaction, attract pollinators and beneficial insects |
Fall Cover Crops (7 options) — Plant after harvest to protect soil over winter
| Crop | Plant By | Terminate | N-Fixing | Soil Benefit |
|---|---|---|---|---|
| Austrian winter peas | Aug 30 | Mar 24 | ✓ Yes | Fixes nitrogen, good for heavy clay soils |
| Crimson clover | Aug 26 | Mar 31 | ✓ Yes | Fixes nitrogen, attracts pollinators in spring |
| Daikon radish | Sep 12 | Mar 31 | — | Deep taproot breaks compaction, excellent for clay soils |
| Hairy vetch | Aug 22 | Mar 24 | ✓ Yes | Excellent nitrogen fixer, good for depleted soils |
| Oats | Sep 23 | Mar 31 | — | Quick biomass, winterkills in cold zones — no spring tillage needed |
| Winter rye | Jul 30 | Mar 24 | — | Suppresses weeds, prevents erosion, breaks up compacted soil |
| Winter wheat | Aug 4 | Mar 24 | — | Erosion control, weed suppression, good biomass |
Wind & Microclimate in Jefferson County
Quick context: New gardeners under-plan for wind. Jefferson County averages 10.0 mph — fine for most days. But every region has its windy days, and the first time a row of unstaked peppers leans over after a storm is a lesson you only need once.
Wind dries soil, stresses plants, and affects frost patterns. Understanding your exposure helps with garden placement.
Seasonal Wind Speed
Spring: 13 mph Summer: 10 mph
Fall: 10 mph Winter: 14 mph
Prevailing wind: SW. Moderate wind — consider a temporary windbreak for young seedlings.
Windbreak Benefit
6.9/10
Moderately beneficial — a simple fence or trellis can protect delicate crops from wind stress.
Frost Pocket Risk
Moderate
Some terrain variation (574 ft range). Garden on slopes or higher ground if possible to avoid late-season frost pockets.
Rainwater Harvesting in Jefferson County
How much water you can collect, when to collect it, and what size system you need for your garden.
Why it matters: Building a rainwater system is mostly about doing the math: roof area × annual rainfall × 0.6 = gallons you could realistically capture. For Jefferson County, that's your 41" times your roof.
Annual Collection
20,334 gal
Per 1,000 sq ft of roof area (at 80% collection efficiency)
Recommended Setup
6 rain barrels (55 gal each)
For a typical 500 sq ft garden. Serious collectors: consider a 2,250 gal tank.
Legal Status
Unrestricted
Rainwater harvesting is fully legal in your state with no restrictions.
Best Collection Months
Jan, Feb, Nov, Dec
Highest rainfall months — your barrels will fill up quickly during these months.
Months to Draw From Storage
Jul, Aug
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 40.8 inches of rain per year
- A 1,000 sq ft roof can collect roughly 20,334 gallons annually
- Rainwater harvesting is fully legal in your state
- Use a first-flush diverter to keep roof debris out of your collection
Soil & Growing Conditions in Jefferson County
Soil Type
Silt Loam
Soil pH 5.7–6.8 · Excessively Drained drainage
Native soil is well-suited to most vegetables and herbs with regular compost additions.
Watering Needs
Drought stress: 3.5/10
Low-to-moderate drought stress. Plan to water 1–2 times per week during peak summer. (40.7 in. annual rainfall)
Season Tips
198-day frost-free season
Plenty of time for warm-season crops. Start heat-lovers indoors 6–8 weeks before last frost to maximise your harvest window.
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 Jefferson County
114 vegetables that grow well in Zone 8b with planting dates for Jefferson County.
Show all 114 vegetables with planting dates
| Plant | Start Indoors | Direct Sow | Transplant | Fall Plant | Harvest | Days to Maturity |
|---|---|---|---|---|---|---|
| Acorn Squash | Mar 17 | Apr 21 | Apr 28 | — | Jul 21 – Aug 25 | 80–100 |
| Amaranth | Feb 24 | Apr 21 | Apr 28 | — | Jul 28 – Sep 15 | 90–120 |
| Artichoke | — | — | Apr 28 | — | Sep 1 – Nov 10 | 120–180 |
| Arugula | Mar 10 | Mar 31 | Apr 14 | Aug 20 | May 19 – Jul 21 | 30–50 |
| Asparagus | — | — | Apr 28 | — | — | 730–1095 |
| Beets | — | Mar 31 | — | Aug 20 | May 26 – Jun 23 | 50–70 |
| Belgian Endive | Mar 10 | Mar 31 | Apr 14 | Aug 20 | Aug 4 – Sep 29 | 110–150 |
| Bitter Melon | Feb 24 | Apr 21 | Apr 28 | — | Jun 30 – Aug 11 | 60–90 |
| Black Beans | — | Apr 21 | — | — | Jul 21 – Sep 8 | 90–120 |
| Bok Choy | Mar 10 | Mar 31 | Apr 14 | Aug 20 | May 26 – Jun 30 | 40–60 |
| Broccoli | Mar 10 | Mar 31 | Apr 14 | Aug 20 | Jun 16 – Jul 28 | 60–90 |
| Broccoli Rabe | Mar 10 | Mar 31 | Apr 14 | Aug 20 | May 26 – Jun 30 | 40–60 |
| Brussels Sprouts | Mar 10 | Mar 31 | Apr 14 | Aug 20 | Jul 14 – Sep 8 | 90–130 |
| Butternut Squash | Mar 17 | Apr 21 | Apr 28 | — | Jul 28 – Sep 1 | 85–110 |
| Cabbage | Mar 10 | Mar 31 | Apr 14 | Aug 20 | Jun 16 – Aug 11 | 60–100 |
| Calabash | Feb 24 | Apr 21 | Apr 28 | — | Jul 21 – Sep 15 | 80–120 |
| Cardoon | — | — | Apr 28 | — | Sep 1 – Oct 13 | 120–150 |
| Carrots | — | Mar 31 | — | Aug 20 | Jun 2 – Jul 7 | 60–80 |
| Cauliflower | Mar 10 | Mar 31 | Apr 14 | Aug 20 | Jun 9 – Aug 11 | 55–100 |
| Celeriac | Mar 10 | Mar 31 | Apr 14 | Aug 20 | Jul 28 – Sep 1 | 100–120 |
| Celery | Mar 10 | Mar 31 | Apr 14 | Aug 20 | Jul 7 – Sep 1 | 80–120 |
| Celtuce | Mar 10 | Mar 31 | Apr 14 | Aug 20 | Jun 16 – Jul 28 | 60–90 |
| Chard | Mar 10 | Mar 31 | Apr 14 | Aug 20 | Jun 9 – Jul 28 | 50–60 |
| Chayote | Feb 24 | Apr 21 | Apr 28 | — | Sep 1 – Nov 10 | 120–180 |
| Chickpeas | Mar 10 | Mar 31 | Apr 14 | Aug 20 | Jul 7 – Aug 18 | 80–110 |
| Chicory | Mar 10 | Mar 31 | Apr 14 | Aug 20 | Jun 16 – Jul 28 | 60–85 |
| Chinese Cabbage | Mar 10 | Mar 31 | Apr 14 | Aug 20 | Jun 9 – Jul 7 | 50–70 |
| Christmas Lima Beans | Feb 24 | Apr 21 | Apr 28 | — | Jul 21 – Aug 25 | 80–100 |
| Collard Greens | Mar 10 | Mar 31 | Apr 14 | Aug 20 | Jun 9 – Aug 11 | 55–75 |
| Corn | — | Apr 21 | — | — | Jun 23 – Aug 18 | 60–100 |
| Cowpeas | — | Apr 21 | — | — | Jun 23 – Aug 4 | 60–90 |
| Cress | Mar 10 | Mar 31 | Apr 14 | Aug 20 | Apr 28 – May 19 | 14–21 |
| Crookneck Squash | Mar 17 | Apr 21 | Apr 28 | — | Jun 16 – Jul 14 | 45–60 |
| Crosne | — | Mar 31 | — | Aug 20 | Sep 1 – Nov 3 | 150–200 |
| Cucumber | Mar 17 | Apr 21 | Apr 28 | — | Jun 23 – Aug 18 | 50–70 |
| Daikon | — | Mar 31 | — | Aug 20 | May 26 – Jun 23 | 50–70 |
| Delicata Squash | Mar 17 | Apr 21 | Apr 28 | — | Jul 21 – Aug 25 | 80–100 |
| Edamame | — | Apr 21 | — | — | Jul 7 – Aug 18 | 75–100 |
| Eggplant | Feb 10 | Apr 21 | Apr 28 | — | Jul 7 – Sep 8 | 65–85 |
| Endive | Mar 10 | Mar 31 | Apr 14 | Aug 20 | Jun 2 – Jul 7 | 45–65 |
| Escarole | Mar 10 | Mar 31 | Apr 14 | Aug 20 | Jun 9 – Jul 7 | 50–70 |
| Fava Beans | Mar 10 | Mar 31 | Apr 14 | Aug 20 | Jun 30 – Aug 11 | 75–100 |
| Fennel | Feb 24 | Apr 21 | Apr 28 | — | Jun 30 – Aug 11 | 60–90 |
| Garlic | — | — | — | Sep 17 | Dec 17 – Jun 3 | 90–240 |
| Ginger | Feb 24 | Apr 21 | Apr 28 | — | Dec 29 – Jan 12 | 240–300 |
| Green Beans | — | Apr 21 | — | — | Jun 16 – Aug 11 | 50–65 |
| Horseradish | — | — | Apr 28 | — | Sep 1 – Nov 10 | 120–180 |
| Hot Peppers | Feb 10 | Apr 21 | Apr 28 | — | Jul 7 – Oct 13 | 70–120 |
| Hubbard Squash | Mar 17 | Apr 21 | Apr 28 | — | Aug 11 – Sep 15 | 100–120 |
| Jicama | Feb 24 | Apr 21 | Apr 28 | — | Sep 1 – Nov 10 | 120–180 |
| Kabocha | Mar 17 | Apr 21 | Apr 28 | — | Jul 28 – Aug 25 | 85–100 |
| Kai Lan | Mar 10 | Mar 31 | Apr 14 | Aug 20 | Jun 2 – Jun 30 | 45–60 |
| Kale | Mar 10 | Mar 31 | Apr 14 | Aug 20 | Jun 9 – Aug 4 | 50–70 |
| Kidney Beans | — | Apr 21 | — | — | Jul 21 – Aug 25 | 85–110 |
| Kohlrabi | Mar 10 | Mar 31 | Apr 14 | Aug 20 | Jun 2 – Jul 7 | 45–65 |
| Komatsuna | Mar 10 | Mar 31 | Apr 14 | Aug 20 | May 19 – Jun 23 | 35–50 |
| Leeks | Mar 10 | Mar 31 | Apr 14 | Aug 20 | Jul 14 – Sep 29 | 90–150 |
| Lentils | Mar 10 | Mar 31 | Apr 14 | Aug 20 | Jul 7 – Aug 18 | 80–110 |
| Lettuce | Mar 10 | Mar 31 | Apr 14 | Aug 20 | May 19 – Jul 28 | 30–60 |
| Lima Beans | — | Apr 21 | — | — | Jun 23 – Aug 4 | 60–90 |
| Loofah | Feb 24 | Apr 21 | Apr 28 | — | Aug 11 – Oct 13 | 100–150 |
| Luffa | Feb 24 | Apr 21 | Apr 28 | — | Jul 28 – Oct 13 | 90–150 |
| Mache | Mar 10 | Mar 31 | Apr 14 | Aug 20 | May 26 – Jun 30 | 40–60 |
| Malabar Spinach | Feb 24 | Apr 21 | Apr 28 | — | Jun 23 – Jul 21 | 55–70 |
| Melon | Mar 17 | Apr 21 | Apr 28 | — | Jul 7 – Aug 25 | 70–100 |
| Microgreens | Mar 10 | Mar 31 | Apr 14 | Aug 20 | Apr 21 – May 19 | 7–21 |
| Mitsuba | Mar 10 | Mar 31 | Apr 7 | Aug 20 | Jun 2 – Jul 28 | 50–70 |
| Mizuna | Mar 10 | Mar 31 | Apr 14 | Aug 20 | May 19 – Jun 16 | 30–45 |
| Mustard Greens | Mar 10 | Mar 31 | Apr 14 | Aug 20 | May 19 – Jul 21 | 30–50 |
| Napa Cabbage | Mar 10 | Mar 31 | Apr 14 | Aug 20 | Jun 9 – Jul 14 | 55–75 |
| New Zealand Spinach | Feb 24 | Apr 21 | Apr 28 | — | Jun 23 – Jul 21 | 55–70 |
| Okra | Feb 24 | Apr 21 | Apr 28 | — | Jun 23 – Aug 18 | 50–65 |
| Onion | Mar 10 | Mar 31 | Apr 14 | Aug 20 | Jul 14 – Sep 1 | 90–120 |
| Pac Choi | Mar 10 | Mar 31 | Apr 14 | Aug 20 | May 26 – Jun 23 | 40–55 |
| Parsnip | — | Mar 31 | — | Aug 20 | Jul 14 – Aug 25 | 100–130 |
| Patty Pan Squash | Mar 17 | Apr 21 | Apr 28 | — | Jun 16 – Jul 14 | 45–60 |
| Peas | Mar 10 | Mar 31 | Apr 14 | Aug 20 | Jun 9 – Aug 4 | 55–70 |
| Peppers | Feb 10 | Apr 21 | Apr 28 | — | Jun 30 – Sep 8 | 60–90 |
| Pole Beans | Feb 24 | Apr 21 | Apr 28 | — | Jun 23 – Aug 18 | 55–70 |
| Potatoes | Feb 24 | Apr 21 | Apr 28 | — | Jul 7 – Sep 15 | 70–120 |
| Pumpkin | Mar 17 | Apr 21 | Apr 28 | — | Jul 28 – Sep 15 | 85–120 |
| Purslane | Mar 10 | Mar 31 | Apr 14 | Aug 20 | May 26 – Jun 30 | 40–60 |
| Radicchio | Mar 10 | Mar 31 | Apr 14 | Aug 20 | Jun 16 – Jul 21 | 60–80 |
| Radish | — | Mar 31 | — | Aug 20 | Apr 28 – May 19 | 22–35 |
| Rhubarb | — | — | May 5 | — | — | 365–730 |
| Romanesco | Mar 10 | Mar 31 | Apr 14 | Aug 20 | Jun 30 – Aug 11 | 75–100 |
| Rutabaga | — | Mar 31 | — | Aug 20 | Jun 23 – Jul 28 | 80–100 |
| Salsify | — | Mar 31 | — | Aug 20 | Jul 14 – Aug 25 | 100–130 |
| Savoy Cabbage | Mar 10 | Mar 31 | Apr 14 | Aug 20 | Jun 23 – Aug 18 | 70–110 |
| Scallions | Mar 10 | Mar 31 | Apr 14 | Aug 20 | Jun 9 – Jul 7 | 50–70 |
| Scarlet Runner Beans | Feb 24 | Apr 21 | Apr 28 | — | Jun 30 – Aug 4 | 60–80 |
| Shallot | Mar 10 | Mar 31 | Apr 14 | Aug 20 | Jul 14 – Sep 1 | 90–120 |
| Shiso | Feb 24 | Apr 21 | Apr 28 | — | Jun 23 – Aug 18 | 50–70 |
| Snap Peas | Feb 24 | Apr 21 | Apr 28 | — | Jun 23 – Aug 18 | 55–70 |
| Snow Peas | Mar 10 | Mar 31 | Apr 14 | Aug 20 | Jun 9 – Aug 4 | 50–65 |
| Soybeans | — | Apr 21 | — | — | Jul 14 – Sep 8 | 80–120 |
| Spaghetti Squash | Mar 17 | Apr 21 | Apr 28 | — | Jul 28 – Aug 25 | 85–100 |
| Spinach | Mar 10 | Mar 31 | Apr 14 | Aug 20 | May 19 – Jul 21 | 35–50 |
| Squash (Summer) | Mar 17 | Apr 21 | Apr 28 | — | Jun 16 – Aug 18 | 45–65 |
| Squash (Winter) | Mar 17 | Apr 21 | Apr 28 | — | Jul 21 – Sep 15 | 80–120 |
| Sunchoke | — | — | Apr 28 | — | Aug 18 – Oct 13 | 110–150 |
| Sweet Corn | — | Apr 21 | — | — | Jun 23 – Aug 4 | 60–90 |
| Sweet Potatoes | Feb 24 | Apr 21 | Apr 28 | — | Jul 28 – Sep 15 | 90–120 |
| Tatsoi | Mar 10 | Mar 31 | Apr 14 | Aug 20 | May 19 – Jun 23 | 35–50 |
| Tomatillo | Feb 24 | Apr 21 | Apr 28 | — | Jun 30 – Sep 8 | 60–85 |
| Tomatoes | Feb 24 | Apr 21 | Apr 28 | — | Jun 30 – Sep 8 | 60–85 |
| Turmeric | Feb 24 | Apr 21 | Apr 28 | — | Dec 29 – Jan 12 | 240–300 |
| Turnip | — | Mar 31 | — | Aug 20 | May 12 – Jun 16 | 40–60 |
| Watercress | Mar 10 | Mar 31 | Apr 14 | Aug 20 | May 26 – Jun 30 | 40–60 |
| Watermelon | Mar 17 | Apr 21 | Apr 28 | — | Jul 7 – Aug 25 | 70–100 |
| Wax Beans | — | Apr 21 | — | — | Jun 16 – Aug 11 | 50–65 |
| Winter Melon | Feb 24 | Apr 21 | Apr 28 | — | Jul 28 – Sep 15 | 90–120 |
| Yard Long Beans | Feb 24 | Apr 21 | Apr 28 | — | Jun 23 – Aug 4 | 55–80 |
| Zucchini | Mar 17 | Apr 21 | Apr 28 | — | Jun 16 – Aug 11 | 45–60 |
🍓 Fruits to Grow in Jefferson County
27 fruits that grow well in Zone 8b with planting dates for Jefferson County.
Show all 27 fruits with planting dates
| Plant | Start Indoors | Direct Sow | Transplant | Fall Plant | Harvest | Days to Maturity |
|---|---|---|---|---|---|---|
| Alpine Strawberries | — | — | May 5 | — | Aug 4 – Nov 17 | 90–180 |
| Aronia | — | — | May 5 | — | — | 730–1095 |
| Blackberries | — | — | May 5 | — | — | 365–730 |
| Blueberries | — | — | May 5 | — | — | 730–1095 |
| Boysenberries | — | — | May 5 | — | — | 365–730 |
| Cantaloupe | — | — | May 5 | — | Jul 14 – Aug 18 | 70–90 |
| Che Fruit | — | — | May 5 | — | — | 1095–1825 |
| Elderberries | — | — | May 5 | — | — | 730–1095 |
| Figs | — | — | May 5 | — | — | 730–1825 |
| Goji Berries | — | — | May 5 | — | — | 730–1095 |
| Gooseberries | — | — | May 5 | — | — | 730–1095 |
| Grapes | — | — | May 5 | — | — | 730–1095 |
| Ground Cherry | — | — | May 5 | — | Jul 14 – Sep 8 | 65–80 |
| Hardy Kiwi | — | — | May 5 | — | — | 1095–1825 |
| Honeydew | — | — | May 5 | — | Jul 28 – Sep 8 | 80–110 |
| Jostaberry | — | — | May 5 | — | — | 730–1095 |
| Kiwi | — | — | May 5 | — | — | 1095–1825 |
| Loquat | — | — | May 5 | — | — | 730–1825 |
| Medlar | — | — | May 5 | — | — | 1095–1825 |
| Mulberries | — | — | May 5 | — | — | 730–1825 |
| Pawpaw | — | — | May 5 | — | — | 1095–2555 |
| Persimmon | — | — | May 5 | — | — | 1095–2555 |
| Pomegranate | — | — | May 5 | — | — | 730–1095 |
| Quince | — | — | May 5 | — | — | 1095–1825 |
| Raspberries | — | — | May 5 | — | — | 365–730 |
| Serviceberries | — | — | May 5 | — | — | 730–1095 |
| Strawberries | — | — | May 5 | — | Aug 4 – Jan 19 | 90–365 |
🌿 Herbs to Grow in Jefferson County
39 herbs that grow well in Zone 8b with planting dates for Jefferson County.
Show all 39 herbs with planting dates
| Plant | Start Indoors | Direct Sow | Transplant | Fall Plant | Harvest | Days to Maturity |
|---|---|---|---|---|---|---|
| Angelica | Mar 10 | Mar 31 | Apr 7 | Aug 20 | — | 365–730 |
| Anise | Mar 10 | Mar 31 | Apr 7 | Aug 20 | Jul 7 – Sep 22 | 90–120 |
| Basil | Feb 24 | Apr 21 | Apr 28 | — | Jun 23 – Aug 25 | 50–75 |
| Bee Balm | — | — | Apr 21 | — | Jul 21 – Oct 6 | 90–120 |
| Borage | Mar 10 | Mar 31 | Apr 7 | Aug 20 | Jun 2 – Jul 21 | 50–60 |
| Caraway | Mar 10 | Mar 31 | Apr 7 | Aug 20 | — | 365–450 |
| Catnip | — | — | Apr 21 | — | Jun 23 – Aug 25 | 60–80 |
| Chamomile | Mar 10 | Mar 31 | Apr 7 | Aug 20 | Jun 9 – Aug 18 | 60–90 |
| Chervil | Mar 10 | Mar 31 | Apr 7 | Aug 20 | May 19 – Jul 21 | 40–60 |
| Chives | — | — | Apr 21 | — | Jun 23 – Sep 1 | 60–90 |
| Cilantro | Mar 10 | Mar 31 | Apr 7 | Aug 20 | May 19 – Jul 21 | 40–60 |
| Comfrey | — | — | Apr 21 | — | Jun 23 – Sep 1 | 60–90 |
| Cumin | Mar 10 | Mar 31 | Apr 7 | Aug 20 | Jul 21 – Sep 22 | 100–120 |
| Dill | Mar 10 | Mar 31 | Apr 7 | Aug 20 | May 19 – Jul 21 | 40–60 |
| Epazote | Feb 24 | Apr 21 | Apr 28 | — | Jun 16 – Aug 11 | 45–60 |
| Fennel (herb) | Mar 10 | Mar 31 | Apr 7 | Aug 20 | Jun 9 – Aug 18 | 60–90 |
| Feverfew | — | — | Apr 21 | — | Jul 21 – Oct 6 | 90–120 |
| Garlic Chives | — | — | Apr 21 | — | Jun 23 – Sep 1 | 60–90 |
| Horehound | — | — | Apr 21 | — | Jul 7 – Sep 1 | 75–90 |
| Hyssop | — | — | Apr 21 | — | Jun 30 – Sep 1 | 70–90 |
| Lemon Balm | — | — | Apr 21 | — | Jun 23 – Aug 11 | 60–70 |
| Lemon Thyme | — | — | Apr 21 | — | Jun 30 – Sep 1 | 70–90 |
| Lemon Verbena | Feb 24 | Apr 21 | Apr 28 | — | Jun 30 – Sep 8 | 60–90 |
| Lemongrass | Feb 24 | Apr 21 | Apr 28 | — | Jul 14 – Oct 13 | 75–120 |
| Lovage | — | — | Apr 21 | — | Jun 30 – Sep 1 | 70–90 |
| Marjoram | — | — | Apr 21 | — | Jun 23 – Sep 1 | 60–90 |
| Mint | — | — | Apr 21 | — | Jun 23 – Sep 1 | 60–90 |
| Oregano | — | — | Apr 21 | — | Jun 23 – Sep 1 | 60–90 |
| Parsley | Mar 10 | Mar 31 | Apr 7 | Aug 20 | Jun 9 – Aug 11 | 60–80 |
| Rosemary | — | — | Apr 21 | — | Jul 14 – Dec 1 | 80–180 |
| Rue | — | — | Apr 21 | — | Jun 30 – Sep 1 | 70–90 |
| Sage | — | — | Apr 21 | — | Jul 7 – Sep 1 | 75–90 |
| Savory | — | — | Apr 21 | — | Jun 16 – Aug 11 | 50–70 |
| Sorrel | Mar 10 | Mar 31 | Apr 7 | Aug 20 | May 19 – Jul 21 | 40–60 |
| Stevia | Feb 24 | Apr 21 | Apr 28 | — | Jun 30 – Sep 8 | 60–90 |
| Tarragon | — | — | Apr 21 | — | Jun 23 – Sep 1 | 60–90 |
| Thai Basil | Feb 24 | Apr 21 | Apr 28 | — | Jun 23 – Aug 25 | 50–75 |
| Thyme | — | — | Apr 21 | — | Jun 30 – Sep 1 | 70–90 |
| Valerian | — | — | Apr 21 | — | Aug 25 – Dec 1 | 120–180 |
🌸 Flowers to Grow in Jefferson County
54 flowers that grow well in Zone 8b with planting dates for Jefferson County.
Show all 54 flowers with planting dates
| Plant | Start Indoors | Direct Sow | Transplant | Fall Plant | Bloom | Days to Maturity |
|---|---|---|---|---|---|---|
| Ageratum | Mar 3 | Mar 31 | Mar 31 | — | May 26 – Oct 27 | 60–75 |
| Alliums | — | — | — | Oct 1 | Oct 29 – Nov 19 | 28–42 |
| Anemones | — | — | — | Sep 3 | Sep 10 – Oct 8 | 90–120 |
| Astilbe | Feb 17 | — | Apr 14 | — | Jun 23 – Aug 11 | 70–100 |
| Bachelor's Button | — | Feb 24 | Mar 24 | Sep 3 | May 26 – Sep 22 | 60–90 |
| Begonias | Feb 3 | — | Mar 31 | — | Jun 9 – Nov 10 | 70–90 |
| Black-eyed Susan | Feb 17 | Mar 31 | Apr 14 | — | Jun 23 – Nov 17 | 60–80 |
| Bleeding Hearts | Feb 17 | — | Apr 14 | — | Jun 2 – Jun 30 | 60–90 |
| Calendula | — | Feb 24 | Mar 24 | Aug 20 | May 12 – Oct 6 | 50–70 |
| California Poppy | — | — | — | Aug 20 | Oct 29 – Feb 18 | 60–90 |
| Celosia | Mar 17 | Mar 31 | Mar 31 | — | Jun 2 – Nov 10 | 60–90 |
| Columbine | Feb 17 | Apr 14 | Apr 14 | — | Jun 2 – Jun 30 | 70–100 |
| Coreopsis | Feb 17 | Mar 31 | Apr 14 | — | Jun 16 – Nov 10 | 60–80 |
| Cosmos | Mar 17 | Mar 24 | Mar 24 | — | Jun 2 – Nov 3 | 60–90 |
| Crocus | — | — | — | Oct 1 | Sep 3 – Sep 24 | 10–20 |
| Daffodils | — | — | — | Oct 1 | Sep 10 – Oct 8 | 20–40 |
| Dahlias | Mar 24 | Apr 14 | Apr 14 | — | Jun 23 – Dec 8 | 70–120 |
| Daylily | Feb 17 | — | Apr 14 | — | Jun 23 – Nov 24 | 60–90 |
| Dianthus | Feb 17 | Feb 24 | Mar 3 | — | Apr 21 – Jun 30 | 60–80 |
| Echinacea (Purple Coneflower) | Feb 17 | Apr 14 | Apr 14 | — | Jun 23 – Nov 10 | 70–90 |
| Foxglove | Feb 17 | Apr 7 | Apr 7 | — | May 26 – Jun 23 | 80–120 |
| Freesia | — | — | — | Sep 17 | Oct 8 – Nov 12 | 84–112 |
| Gaillardia (Blanket Flower) | Mar 3 | Mar 31 | Mar 31 | — | Jun 9 – Nov 24 | 70–100 |
| Geraniums | Feb 3 | — | Mar 31 | — | Jun 9 – Nov 10 | 70–100 |
| Gladiolus | — | Apr 14 | Apr 14 | — | Jun 23 – Dec 8 | 70–100 |
| Hostas | Feb 10 | — | Apr 14 | — | Jun 23 – Oct 27 | 60–90 |
| Hyacinths | — | — | — | Oct 1 | Sep 24 – Oct 15 | 14–28 |
| Hydrangeas | Feb 10 | — | Apr 7 | — | Jun 16 – Oct 20 | 90–150 |
| Impatiens | Feb 17 | — | Apr 7 | — | Jun 16 – Nov 17 | 60–75 |
| Irises | — | Division | Apr 7 | — | May 26 – Jun 30 | 60–100 |
| Larkspur | — | — | — | Aug 20 | Oct 29 – Feb 18 | 60–90 |
| Lavender | Feb 17 | — | Apr 14 | — | Jun 23 – Sep 29 | 90–120 |
| Lilies | — | Division | Apr 7 | — | Jun 16 – Oct 6 | 70–120 |
| Lobelia | Feb 17 | — | Mar 3 | — | Apr 28 – Jun 9 | 70–80 |
| Lupine | Feb 17 | Apr 14 | Apr 14 | — | Jun 2 – Jun 30 | 75–100 |
| Marigolds | Mar 10 | Mar 31 | Mar 31 | — | May 26 – Oct 13 | 50–70 |
| Nasturtium | Mar 17 | Mar 31 | Mar 31 | — | May 26 – Nov 10 | 55–65 |
| Pansy | Feb 3 | — | Mar 24 | Aug 20 | May 19 – Sep 8 | 70–90 |
| Peonies | — | Division | Apr 14 | — | Jun 9 – Jul 7 | 90–120 |
| Petunia | Feb 17 | — | Apr 7 | — | Jun 16 – Nov 3 | 70–90 |
| Phlox | Feb 17 | Apr 14 | Apr 14 | — | Jun 23 – Sep 1 | 80–110 |
| Portulaca | Mar 17 | Mar 31 | Mar 31 | — | May 19 – Oct 27 | 50–70 |
| Ranunculus | — | — | — | Sep 3 | Sep 17 – Oct 15 | 90–120 |
| Roses | Feb 10 | — | Apr 7 | — | Jun 16 – Nov 17 | 90–180 |
| Salvia | Feb 17 | — | Mar 31 | — | Jun 9 – Nov 10 | 70–90 |
| Sedum (Stonecrop) | Feb 17 | — | Apr 14 | — | Aug 4 – Oct 27 | 60–90 |
| Snapdragon | Feb 3 | Mar 3 | Mar 24 | Aug 20 | Jun 2 – Oct 6 | 70–100 |
| Sunflower | Mar 24 | Mar 31 | Mar 31 | — | Jun 23 – Nov 10 | 70–100 |
| Sweet Alyssum | Mar 3 | Mar 3 | Mar 24 | Sep 3 | May 5 – Sep 8 | 45–60 |
| Sweet Pea | — | — | — | Aug 27 | Nov 5 – Jan 14 | 65–85 |
| Tulips | — | — | — | Oct 1 | Sep 17 – Oct 15 | 15–30 |
| Vinca (Annual) | Feb 3 | — | Mar 31 | — | Jun 9 – Nov 10 | 70–90 |
| Yarrow | Feb 17 | Mar 31 | Apr 14 | — | Jun 16 – Nov 10 | 60–90 |
| Zinnia | Mar 17 | Mar 31 | Mar 31 | — | Jun 9 – Nov 10 | 60–70 |
Monthly Planting Guide for Jefferson County
Gardening Guides & Resources
Helpful guides from The Ultimate Homestead to improve your garden in Jefferson County.
Frequently Asked Questions
What planting zone is Jefferson County, WA?
Jefferson County is in USDA Hardiness Zone 8b. 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 Jefferson County, WA?
Based on 31 years of NOAA weather station data, the median last spring frost in Jefferson County falls around April 14. In 8 out of 10 years, last frost lands between March 23 and May 9 — a 47-day window of variability. Use May 9 as your conservative safe-to-plant date for frost-sensitive crops.
When is the first fall frost in Jefferson County, WA?
The median first fall frost in Jefferson County arrives around October 29. In cold years it can arrive as early as October 11; in mild years as late as November 19. Harvest or protect frost-sensitive crops — tomatoes, peppers, basil, squash — before this date.
How long is the growing season in Jefferson County?
Jefferson County has a frost-free growing season of approximately 198 days. This is enough time for most warm-season crops including tomatoes, peppers, and squash with proper timing.
What is the soil like in Jefferson County for gardening?
Jefferson County has predominantly Silt Loam soil with a pH range of 5.7–6.8 and Excessively Drained drainage. Most vegetables and herbs grow well with standard composting and seasonal soil amendment.
What is grown commercially in Jefferson County?
Jefferson County has commercial agriculture that includes Wheat, Hay, Apples, Potatoes, Hops. These crops reflect the local climate and soil conditions — what succeeds commercially often translates well to home gardens in the same area.
Is Jefferson County a good location for home gardening?
Jefferson County scores 76/100 (Good) on our Microclimate Index, which combines frost reliability, drought pressure, soil challenge, elevation risk, and long-term climate trend. This is an above-average location for home gardening with relatively predictable growing conditions.
Your Jefferson County Garden Planner — Free
A 22-page printable planner built for Jefferson County (Zone 8b). 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