Jefferson County, OR — Planting Guide
Jefferson County is in USDA Zone 6a. The average last spring frost is June 9 and the first fall frost is September 19, giving you a growing season of approximately 102 days.
At an elevation of 21 ft, Jefferson County receives approximately 36.1 in of rainfall annually. Summer highs average 79°F with winter lows around 26°F. The predominant soil type is Silt Loam.
Based on 30 years of NOAA climate station data, the last frost date here varies by 36 days year to year — ranging from May 17 in warm years to June 22 in cold years. The growing season is trending longer by about 4.51 days per decade. Jefferson County scores 61/100 (Good) on the Microclimate Index.
🌡️ Zone
6a (-10°F to -5°F min)
❄️ Last Frost
June 9
🍂 First Frost
September 19
📅 Growing Season
102 days
⛰️ Elevation
21 ft
🌧️ Annual Rainfall
36.1 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 | 4.8 in | 20 days | — | None |
| Feb | 3.7 in | 14 days | — | None |
| Mar | 3.7 in | 15 days | 0.6 in | Moderate |
| Apr | 2.9 in | 11 days | 1.4 in | Moderate |
| May | 1.8 in | 9 days | 2.5 in | High |
| Jun | 1.6 in | 6 days | 2.7 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 | 5 days | 2.7 in | High |
| Oct | 3.2 in | 12 days | 1.1 in | Moderate |
| Nov | 6.1 in | 16 days | — | None |
| Dec | 5.5 in | 19 days | — | None |
Annual total: 36 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
5.3-6.7
Drainage
Well Drained
Frost Risk Probability
Based on 30 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 22 | Oct 6 | 106 days |
| Cautious | Jun 16 | Sep 26 | 102 days |
| Average year | Jun 9 | Sep 19 | 102 days |
| Optimistic | May 30 | Sep 10 | 103 days |
| Aggressive (risky) | May 17 | Aug 31 | 106 days |
Not very — frost dates can vary by ±36 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 4.5 days per decade). Spring is arriving earlier than it used to. Good news for gardeners.
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 Oregon State University Extension Extension Office
Phone: 541-737-2713
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 OR" 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 OR" or check your extension office and local parks department. Facebook groups like "Jefferson County Gardeners" or "Oregon 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
15.4 hours
Summer solstice daylight
Shortest Day
8.6 hours
Winter solstice daylight
Peak Sun Hours
10.9 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 | 2.2 hr | Short day |
| February | 10.2 hr | 3.2 hr | Short day |
| March | 11.6 hr | 3.9 hr | Short day |
| April | 13.3 hr | 5.6 hr | Neutral |
| May | 14.6 hr | 7.3 hr | Long day |
| June | 15.4 hr | 8.4 hr | Long day |
| July | 15.1 hr | 10.9 hr | Long day |
| August | 13.9 hr | 9.2 hr | Neutral |
| September | 12.3 hr | 6.8 hr | Neutral |
| October | 10.7 hr | 4 hr | Short day |
| November | 9.3 hr | 2.4 hr | Short day |
| December | 8.6 hr | 1.9 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 warm enough from May through Oct.
Best Month to Compost
Jun
Microbial activity peaks when soil is warm.
Active Composting
7 months
Solid season. Piles go dormant in winter.
View detailed monthly data
| Month | Soil 4" Deep | Soil 8" Deep | Compost Activity | Time to Finish |
|---|---|---|---|---|
| Jan | 29°F | 39°F | ❄️ Dormant | ~36 weeks |
| Feb | 30°F | 37°F | ❄️ Dormant | ~36 weeks |
| Mar | 39°F | 41°F | ❄️ Dormant | ~36 weeks |
| Apr | 52°F | 49°F | ♻️ Active | ~14 weeks |
| May | 61°F | 59°F | ♻️ Active | ~14 weeks |
| Jun | 74°F | 67°F | 🔥 Peak | ~8 weeks |
| Jul | 79°F | 74°F | 🔥 Peak | ~8 weeks |
| Aug | 80°F | 78°F | 🔥 Peak | ~8 weeks |
| Sep | 76°F | 74°F | 🔥 Peak | ~8 weeks |
| Oct | 63°F | 66°F | ♻️ Active | ~14 weeks |
| Nov | 50°F | 54°F | 🐢 Slow | ~24 weeks |
| Dec | 36°F | 45°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 Jefferson 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
Moderate — watch for mildew and blight during wet periods.
Seasonal Risk
View 6 common pests in your area
| Pest | Risk Level | Peak Months |
|---|---|---|
| Aphids | Moderate | Apr, May, Jun, Jul, Aug, Sep |
| Japanese beetles | Moderate | Jun, Jul, Aug |
| Squash vine borers | Moderate | Jun, Jul |
| Tomato hornworms | Moderate | Jun, Jul, Aug |
| Cucumber beetles | Moderate | May, Jun, Jul |
| Stink bugs | Low | Jun, Jul, Aug, Sep |
Organic pest management tips
- Use row covers on susceptible crops during peak pest months
- Apply neem oil preventatively every 7-14 days during active pest season
- Interplant with strong-scented herbs (basil, marigold) to confuse pests
- Hand-pick larger pests (beetles, caterpillars) in early morning when they're sluggish
- Practice crop rotation — never plant the same family in the same spot within 3 years
Cover Crops for Jefferson County
Cover crops protect bare soil, fix nitrogen, suppress weeds, and improve soil structure — with county-specific planting dates.
Spring Cover Crops (3 options) — Build soil before the main growing season
| Crop | Plant By | Terminate | N-Fixing | Soil Benefit |
|---|---|---|---|---|
| Buckwheat | Jun 15 | Jul 18 | — | Rapid growth, attracts pollinators, suppresses weeds |
| Sorghum-sudan grass | Jun 19 | Jul 11 | — | Massive biomass, breaks compaction, suppresses nematodes |
| White clover | May 15 | Jul 18 | ✓ 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 21 | Aug 22 | — | 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 | Jul 26 | May 19 | ✓ Yes | Fixes nitrogen, good for heavy clay soils |
| Crimson clover | Jul 16 | May 26 | ✓ Yes | Fixes nitrogen, attracts pollinators in spring |
| Daikon radish | Aug 11 | May 19 | — | Deep taproot breaks compaction, excellent for clay soils |
| Hairy vetch | Jun 30 | May 26 | ✓ Yes | Excellent nitrogen fixer, good for depleted soils |
| Oats | Aug 12 | May 26 | — | Quick biomass, winterkills in cold zones — no spring tillage needed |
| Winter rye | Jun 20 | May 19 | — | Suppresses weeds, prevents erosion, breaks up compacted soil |
| Winter wheat | Jun 26 | May 19 | — | 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: 9 mph Summer: 9 mph
Fall: 8 mph Winter: 11 mph
Prevailing wind: SW. Moderate wind — consider a temporary windbreak for young seedlings.
Windbreak Benefit
5/10
Moderately beneficial — a simple fence or trellis can protect delicate crops from wind stress.
Frost Pocket Risk
Moderate
Some terrain variation (582 ft range). Garden on slopes or higher ground if possible to avoid late-season frost pockets.
Rainwater Harvesting Potential
How much water you can collect, when to collect it, and what size system you need for your garden.
Annual Collection
17,942 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 36.0 inches of rain per year
- A 1,000 sq ft roof can collect roughly 17,942 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 5.3–6.7 · Well Drained drainage
Good candidate for raised beds to maximise drainage and extend the season.
Watering Needs
Drought stress: 3.5/10
Low-to-moderate drought stress. Plan to water 1–2 times per week during peak summer. (36.1 in. annual rainfall)
Season Tips
102-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.
Free Garden Planner
Plan your entire garden season — organize planting dates, track what you're growing, and know exactly when to start seeds, transplant, and harvest.
Recommended for Your Garden
Test your soil pH, nitrogen, phosphorus, and potassium levels before planting.
Get instant, accurate soil pH readings to fine-tune your amendments.
Boost soil fertility and structure with rich, well-aged organic compost.
🥬 Vegetables to Grow in Jefferson County
108 vegetables that grow well in Zone 6a with planting dates for Jefferson County.
Show all 108 vegetables with planting dates
| Plant | Start Indoors | Direct Sow | Transplant | Harvest | Days to Maturity |
|---|---|---|---|---|---|
| Acorn Squash | May 5 | Jun 16 | Jun 23 | Sep 15 – Oct 20 | 80–100 |
| Amaranth | Apr 14 | Jun 16 | Jun 23 | Sep 22 – Nov 10 | 90–120 |
| Arugula | May 5 | May 26 | Jun 9 | Jul 14 – Sep 15 | 30–50 |
| Asparagus | — | — | Jun 23 | — | 730–1095 |
| Beets | — | May 26 | — | Jul 21 – Aug 18 | 50–70 |
| Belgian Endive | May 5 | May 26 | Jun 9 | Sep 29 – Nov 24 | 110–150 |
| Bitter Melon | Apr 14 | Jun 16 | Jun 23 | Aug 25 – Oct 6 | 60–90 |
| Black Beans | — | Jun 16 | — | Sep 15 – Nov 3 | 90–120 |
| Bok Choy | May 5 | May 26 | Jun 9 | Jul 21 – Aug 25 | 40–60 |
| Broccoli | May 5 | May 26 | Jun 9 | Aug 11 – Sep 22 | 60–90 |
| Broccoli Rabe | May 5 | May 26 | Jun 9 | Jul 21 – Aug 25 | 40–60 |
| Brussels Sprouts | May 5 | May 26 | Jun 9 | Sep 8 – Nov 3 | 90–130 |
| Butternut Squash | May 5 | Jun 16 | Jun 23 | Sep 22 – Oct 27 | 85–110 |
| Cabbage | May 5 | May 26 | Jun 9 | Aug 11 – Oct 6 | 60–100 |
| Calabash | Apr 14 | Jun 16 | Jun 23 | Sep 15 – Nov 10 | 80–120 |
| Carrots | — | May 26 | — | Jul 28 – Sep 1 | 60–80 |
| Cauliflower | May 5 | May 26 | Jun 9 | Aug 4 – Oct 6 | 55–100 |
| Celeriac | May 5 | May 26 | Jun 9 | Sep 22 – Oct 27 | 100–120 |
| Celery | May 5 | May 26 | Jun 9 | Sep 1 – Oct 27 | 80–120 |
| Celtuce | May 5 | May 26 | Jun 9 | Aug 11 – Sep 22 | 60–90 |
| Chard | May 5 | May 26 | Jun 9 | Aug 4 – Sep 22 | 50–60 |
| Chickpeas | May 5 | May 26 | Jun 9 | Sep 1 – Oct 13 | 80–110 |
| Chicory | May 5 | May 26 | Jun 9 | Aug 11 – Sep 22 | 60–85 |
| Chinese Cabbage | May 5 | May 26 | Jun 9 | Aug 4 – Sep 1 | 50–70 |
| Christmas Lima Beans | Apr 14 | Jun 16 | Jun 23 | Sep 15 – Oct 20 | 80–100 |
| Collard Greens | May 5 | May 26 | Jun 9 | Aug 4 – Oct 6 | 55–75 |
| Corn | — | Jun 16 | — | Aug 18 – Oct 13 | 60–100 |
| Cowpeas | — | Jun 16 | — | Aug 18 – Sep 29 | 60–90 |
| Cress | May 5 | May 26 | Jun 9 | Jun 23 – Jul 14 | 14–21 |
| Crookneck Squash | May 5 | Jun 16 | Jun 23 | Aug 11 – Sep 8 | 45–60 |
| Crosne | — | May 26 | — | Oct 27 – Dec 8 | 150–200 |
| Cucumber | May 5 | Jun 16 | Jun 23 | Aug 18 – Oct 13 | 50–70 |
| Daikon | — | May 26 | — | Jul 21 – Aug 18 | 50–70 |
| Delicata Squash | May 5 | Jun 16 | Jun 23 | Sep 15 – Oct 20 | 80–100 |
| Edamame | — | Jun 16 | — | Sep 1 – Oct 13 | 75–100 |
| Eggplant | Mar 31 | Jun 16 | Jun 23 | Sep 1 – Nov 3 | 65–85 |
| Endive | May 5 | May 26 | Jun 9 | Jul 28 – Sep 1 | 45–65 |
| Escarole | May 5 | May 26 | Jun 9 | Aug 4 – Sep 1 | 50–70 |
| Fava Beans | May 5 | May 26 | Jun 9 | Aug 25 – Oct 6 | 75–100 |
| Fennel | Apr 14 | Jun 16 | Jun 23 | Aug 25 – Oct 6 | 60–90 |
| Garlic | — | — | — | — | 90–240 |
| Green Beans | — | Jun 16 | — | Aug 11 – Oct 6 | 50–65 |
| Horseradish | — | — | Jun 23 | Oct 27 – Jan 5 | 120–180 |
| Hot Peppers | Mar 31 | Jun 16 | Jun 23 | Sep 1 – Dec 8 | 70–120 |
| Hubbard Squash | May 5 | Jun 16 | Jun 23 | Oct 6 – Nov 10 | 100–120 |
| Kabocha | May 5 | Jun 16 | Jun 23 | Sep 22 – Oct 20 | 85–100 |
| Kai Lan | May 5 | May 26 | Jun 9 | Jul 28 – Aug 25 | 45–60 |
| Kale | May 5 | May 26 | Jun 9 | Aug 4 – Sep 29 | 50–70 |
| Kidney Beans | — | Jun 16 | — | Sep 15 – Oct 20 | 85–110 |
| Kohlrabi | May 5 | May 26 | Jun 9 | Jul 28 – Sep 1 | 45–65 |
| Komatsuna | May 5 | May 26 | Jun 9 | Jul 14 – Aug 18 | 35–50 |
| Leeks | May 5 | May 26 | Jun 9 | Sep 8 – Nov 24 | 90–150 |
| Lentils | May 5 | May 26 | Jun 9 | Sep 1 – Oct 13 | 80–110 |
| Lettuce | May 5 | May 26 | Jun 9 | Jul 14 – Sep 22 | 30–60 |
| Lima Beans | — | Jun 16 | — | Aug 18 – Sep 29 | 60–90 |
| Loofah | Apr 14 | Jun 16 | Jun 23 | Oct 6 – Dec 8 | 100–150 |
| Luffa | Apr 14 | Jun 16 | Jun 23 | Sep 22 – Dec 8 | 90–150 |
| Mache | May 5 | May 26 | Jun 9 | Jul 21 – Aug 25 | 40–60 |
| Melon | May 5 | Jun 16 | Jun 23 | Sep 1 – Oct 20 | 70–100 |
| Microgreens | May 5 | May 26 | Jun 9 | Jun 16 – Jul 14 | 7–21 |
| Mitsuba | May 5 | May 26 | Jun 2 | Jul 28 – Sep 22 | 50–70 |
| Mizuna | May 5 | May 26 | Jun 9 | Jul 14 – Aug 11 | 30–45 |
| Mustard Greens | May 5 | May 26 | Jun 9 | Jul 14 – Sep 15 | 30–50 |
| Napa Cabbage | May 5 | May 26 | Jun 9 | Aug 4 – Sep 8 | 55–75 |
| New Zealand Spinach | Apr 14 | Jun 16 | Jun 23 | Aug 18 – Sep 15 | 55–70 |
| Okra | Apr 14 | Jun 16 | Jun 23 | Aug 18 – Oct 13 | 50–65 |
| Onion | May 5 | May 26 | Jun 9 | Sep 8 – Oct 27 | 90–120 |
| Pac Choi | May 5 | May 26 | Jun 9 | Jul 21 – Aug 18 | 40–55 |
| Parsnip | — | May 26 | — | Sep 8 – Oct 20 | 100–130 |
| Patty Pan Squash | May 5 | Jun 16 | Jun 23 | Aug 11 – Sep 8 | 45–60 |
| Peas | May 5 | May 26 | Jun 9 | Aug 4 – Sep 29 | 55–70 |
| Peppers | Mar 31 | Jun 16 | Jun 23 | Aug 25 – Nov 3 | 60–90 |
| Pole Beans | Apr 14 | Jun 16 | Jun 23 | Aug 18 – Oct 13 | 55–70 |
| Potatoes | Apr 14 | Jun 16 | Jun 23 | Sep 1 – Nov 10 | 70–120 |
| Pumpkin | May 5 | Jun 16 | Jun 23 | Sep 22 – Nov 10 | 85–120 |
| Purslane | May 5 | May 26 | Jun 9 | Jul 21 – Aug 25 | 40–60 |
| Radicchio | May 5 | May 26 | Jun 9 | Aug 11 – Sep 15 | 60–80 |
| Radish | — | May 26 | — | Jun 23 – Jul 14 | 22–35 |
| Rhubarb | — | — | Jun 30 | — | 365–730 |
| Romanesco | May 5 | May 26 | Jun 9 | Aug 25 – Oct 6 | 75–100 |
| Rutabaga | — | May 26 | — | Aug 18 – Sep 22 | 80–100 |
| Salsify | — | May 26 | — | Sep 8 – Oct 20 | 100–130 |
| Savoy Cabbage | May 5 | May 26 | Jun 9 | Aug 18 – Oct 13 | 70–110 |
| Scallions | May 5 | May 26 | Jun 9 | Aug 4 – Sep 1 | 50–70 |
| Scarlet Runner Beans | Apr 14 | Jun 16 | Jun 23 | Aug 25 – Sep 29 | 60–80 |
| Shallot | May 5 | May 26 | Jun 9 | Sep 8 – Oct 27 | 90–120 |
| Shiso | Apr 21 | Jun 16 | Jun 23 | Aug 18 – Oct 13 | 50–70 |
| Snap Peas | Apr 14 | Jun 16 | Jun 23 | Aug 18 – Oct 13 | 55–70 |
| Snow Peas | May 5 | May 26 | Jun 9 | Aug 4 – Sep 29 | 50–65 |
| Soybeans | — | Jun 16 | — | Sep 8 – Nov 3 | 80–120 |
| Spaghetti Squash | May 5 | Jun 16 | Jun 23 | Sep 22 – Oct 20 | 85–100 |
| Spinach | May 5 | May 26 | Jun 9 | Jul 14 – Sep 15 | 35–50 |
| Squash (Summer) | May 5 | Jun 16 | Jun 23 | Aug 11 – Oct 13 | 45–65 |
| Squash (Winter) | May 5 | Jun 16 | Jun 23 | Sep 15 – Nov 10 | 80–120 |
| Sunchoke | — | — | Jun 23 | Oct 13 – Dec 8 | 110–150 |
| Sunflower | Apr 14 | Jun 16 | Jun 23 | Sep 1 – Oct 20 | 70–100 |
| Sweet Corn | — | Jun 16 | — | Aug 18 – Sep 29 | 60–90 |
| Sweet Potatoes | Apr 14 | Jun 16 | Jun 23 | Sep 22 – Nov 10 | 90–120 |
| Tatsoi | May 5 | May 26 | Jun 9 | Jul 14 – Aug 18 | 35–50 |
| Tomatillo | Apr 14 | Jun 16 | Jun 23 | Aug 25 – Nov 3 | 60–85 |
| Tomatoes | Apr 14 | Jun 16 | Jun 23 | Aug 25 – Nov 3 | 60–85 |
| Turnip | — | May 26 | — | Jul 7 – Aug 11 | 40–60 |
| Watercress | May 5 | May 26 | Jun 9 | Jul 21 – Aug 25 | 40–60 |
| Watermelon | May 5 | Jun 16 | Jun 23 | Sep 1 – Oct 20 | 70–100 |
| Wax Beans | — | Jun 16 | — | Aug 11 – Oct 6 | 50–65 |
| Winter Melon | Apr 14 | Jun 16 | Jun 23 | Sep 22 – Nov 10 | 90–120 |
| Yard Long Beans | Apr 14 | Jun 16 | Jun 23 | Aug 18 – Sep 29 | 55–80 |
| Zucchini | May 5 | Jun 16 | Jun 23 | Aug 11 – Oct 6 | 45–60 |
🍓 Fruits to Grow in Jefferson County
27 fruits that grow well in Zone 6a with planting dates for Jefferson County.
Show all 27 fruits with planting dates
| Plant | Start Indoors | Direct Sow | Transplant | Harvest | Days to Maturity |
|---|---|---|---|---|---|
| Alpine Strawberries | — | — | Jun 30 | Sep 29 – Jan 12 | 90–180 |
| Aronia | — | — | Jun 30 | — | 730–1095 |
| Blackberries | — | — | Jun 30 | — | 365–730 |
| Blueberries | — | — | Jun 30 | — | 730–1095 |
| Boysenberries | — | — | Jun 30 | — | 365–730 |
| Cantaloupe | — | — | Jun 30 | Sep 8 – Oct 13 | 70–90 |
| Che Fruit | — | — | Jun 30 | — | 1095–1825 |
| Cranberries | — | — | Jun 30 | — | 730–1095 |
| Currants | — | — | Jun 30 | — | 730–1095 |
| Elderberries | — | — | Jun 30 | — | 730–1095 |
| Goji Berries | — | — | Jun 30 | — | 730–1095 |
| Gooseberries | — | — | Jun 30 | — | 730–1095 |
| Grapes | — | — | Jun 30 | — | 730–1095 |
| Ground Cherry | — | — | Jun 30 | Sep 8 – Nov 3 | 65–80 |
| Hardy Kiwi | — | — | Jun 30 | — | 1095–1825 |
| Haskaps | — | — | Jun 30 | — | 730–1095 |
| Honeydew | — | — | Jun 30 | Sep 22 – Nov 3 | 80–110 |
| Jostaberry | — | — | Jun 30 | — | 730–1095 |
| Lingonberries | — | — | Jun 30 | — | 730–1095 |
| Medlar | — | — | Jun 30 | — | 1095–1825 |
| Mulberries | — | — | Jun 30 | — | 730–1825 |
| Pawpaw | — | — | Jun 30 | — | 1095–2555 |
| Persimmon | — | — | Jun 30 | — | 1095–2555 |
| Quince | — | — | Jun 30 | — | 1095–1825 |
| Raspberries | — | — | Jun 30 | — | 365–730 |
| Serviceberries | — | — | Jun 30 | — | 730–1095 |
| Strawberries | — | — | Jun 30 | Sep 29 – Jan 12 | 90–365 |
🌿 Herbs to Grow in Jefferson County
38 herbs that grow well in Zone 6a with planting dates for Jefferson County.
Show all 38 herbs with planting dates
| Plant | Start Indoors | Direct Sow | Transplant | Harvest | Days to Maturity |
|---|---|---|---|---|---|
| Angelica | May 5 | May 26 | Jun 2 | — | 365–730 |
| Anise | May 5 | May 26 | Jun 2 | Sep 1 – Nov 17 | 90–120 |
| Basil | Apr 21 | Jun 16 | Jun 23 | Aug 18 – Oct 20 | 50–75 |
| Bee Balm | — | — | Jun 16 | Sep 15 – Dec 1 | 90–120 |
| Borage | May 5 | May 26 | Jun 2 | Jul 28 – Sep 15 | 50–60 |
| Caraway | May 5 | May 26 | Jun 2 | — | 365–450 |
| Catnip | — | — | Jun 16 | Aug 18 – Oct 20 | 60–80 |
| Chamomile | May 5 | May 26 | Jun 2 | Aug 4 – Oct 13 | 60–90 |
| Chervil | May 5 | May 26 | Jun 2 | Jul 14 – Sep 15 | 40–60 |
| Chives | — | — | Jun 16 | Aug 18 – Oct 27 | 60–90 |
| Cilantro | May 5 | May 26 | Jun 2 | Jul 14 – Sep 15 | 40–60 |
| Comfrey | — | — | Jun 16 | Aug 18 – Oct 27 | 60–90 |
| Cumin | May 5 | May 26 | Jun 2 | Sep 15 – Nov 17 | 100–120 |
| Dill | May 5 | May 26 | Jun 2 | Jul 14 – Sep 15 | 40–60 |
| Echinacea | — | — | Jun 16 | Oct 20 – Dec 29 | 120–180 |
| Epazote | Apr 21 | Jun 16 | Jun 23 | Aug 11 – Oct 6 | 45–60 |
| Fennel (herb) | May 5 | May 26 | Jun 2 | Aug 4 – Oct 13 | 60–90 |
| Feverfew | — | — | Jun 16 | Sep 15 – Dec 1 | 90–120 |
| Garlic Chives | — | — | Jun 16 | Aug 18 – Oct 27 | 60–90 |
| Horehound | — | — | Jun 16 | Sep 1 – Oct 27 | 75–90 |
| Hyssop | — | — | Jun 16 | Aug 25 – Oct 27 | 70–90 |
| Lavender | — | — | Jun 16 | Sep 15 – Dec 29 | 90–200 |
| Lemon Balm | — | — | Jun 16 | Aug 18 – Oct 6 | 60–70 |
| Lemon Thyme | — | — | Jun 16 | Aug 25 – Oct 27 | 70–90 |
| Lovage | — | — | Jun 16 | Aug 25 – Oct 27 | 70–90 |
| Marjoram | — | — | Jun 16 | Aug 18 – Oct 27 | 60–90 |
| Mint | — | — | Jun 16 | Aug 18 – Oct 27 | 60–90 |
| Oregano | — | — | Jun 16 | Aug 18 – Oct 27 | 60–90 |
| Parsley | May 5 | May 26 | Jun 2 | Aug 4 – Oct 6 | 60–80 |
| Rue | — | — | Jun 16 | Aug 25 – Oct 27 | 70–90 |
| Sage | — | — | Jun 16 | Sep 1 – Oct 27 | 75–90 |
| Savory | — | — | Jun 16 | Aug 11 – Oct 6 | 50–70 |
| Sorrel | May 5 | May 26 | Jun 2 | Jul 14 – Sep 15 | 40–60 |
| Tarragon | — | — | Jun 16 | Aug 18 – Oct 27 | 60–90 |
| Thai Basil | Apr 21 | Jun 16 | Jun 23 | Aug 18 – Oct 20 | 50–75 |
| Thyme | — | — | Jun 16 | Aug 25 – Oct 27 | 70–90 |
| Valerian | — | — | Jun 16 | Oct 20 – Dec 29 | 120–180 |
| Yarrow | — | — | Jun 16 | Sep 15 – Dec 1 | 90–120 |
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, OR?
Jefferson 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 Jefferson County, OR?
Based on 30 years of NOAA weather station data, the median last spring frost in Jefferson County falls around June 9. In 8 out of 10 years, last frost lands between May 17 and June 22 — a 36-day window of variability. Use June 22 as your conservative safe-to-plant date for frost-sensitive crops.
When is the first fall frost in Jefferson County, OR?
The median first fall frost in Jefferson County arrives around September 19. In cold years it can arrive as early as August 31; in mild years as late as October 6. 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 102 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 4.51 days per decade.
What is the soil like in Jefferson County for gardening?
Jefferson County has predominantly Silt Loam soil with a pH range of 5.3–6.7 and Well 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, Apples, Potatoes, Cattle. 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 61/100 (Good) on our Microclimate Index, which combines frost reliability, drought pressure, soil challenge, elevation risk, and long-term climate trend. Conditions here are moderate — most common crops grow well with standard timing and care.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Jefferson County gardeners in Zone 6a organize planting dates, track what's growing, and never miss a planting window.
Get Your Free Garden Planner →Free download. Plan your entire garden season in minutes.
