San Luis Obispo County, CA — Planting Guide
San Luis Obispo County, California gardeners: here's your May plan
Your garden in San Luis Obispo County, California is working on a schedule, even when you're not. Here's where you should be this May.
-
Start basil, peppers, and pole beans indoors
You're about 27 weeks out from your last frost — the perfect window to get these germinating indoors.
-
Collect basil, carrots, and cucumber at their peak
Don't tug. Use scissors or pruners for clean cuts — torn stems invite disease.
June will be here before you know it — start on
- First harvests: basil, carrots, and cucumber
San Luis Obispo County is in USDA Zone 10a. The average last spring frost is March 23 and the first fall frost is November 9, giving you a growing season of approximately 231 days.
At an elevation of 2,412 ft, San Luis Obispo County receives approximately 18.4 in of rainfall annually. Summer highs average 98°F with winter lows around 50°F. The predominant soil type is Loam.
Based on 31 years of NOAA climate station data, the last frost date here varies by 71 days year to year — ranging from February 4 in warm years to April 16 in cold years. The growing season is trending shorter by about 2.91 days per decade. San Luis Obispo County scores 40/100 (Moderate) on the Microclimate Index.
🌡️ Zone
10a (°F to °F min)
❄️ Last Frost
March 23
🍂 First Frost
November 9
📅 Growing Season
231 days
⛰️ Elevation
2,412 ft
🌧️ Annual Rainfall
18.4 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 in | 11 days | — | None |
| Feb | 3.9 in | 10 days | 0.4 in | Low |
| Mar | 2.8 in | 8 days | 1.5 in | Moderate |
| Apr | 1.6 in | 4 days | 2.7 in | High |
| May | 0.5 in | 2 days | 3.8 in | Critical |
| Jun | 0.1 in | 1 days | 4.2 in | Critical |
| Jul | 0 in | 0 days | 4.3 in | Critical |
| Aug | 0 in | 0 days | 4.3 in | Critical |
| Sep | 0.2 in | 0 days | 4.1 in | Critical |
| Oct | 0.8 in | 2 days | 3.5 in | Critical |
| Nov | 1.8 in | 5 days | 2.5 in | High |
| Dec | 2.8 in | 8 days | — | None |
Annual total: 18.5 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.
San Luis Obispo County Soil Profile
Soil Type
Loam
Soil pH
6.6-7.8
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) | Apr 16 | Dec 1 | 229 days |
| Cautious | Apr 4 | Nov 21 | 231 days |
| Average year | Mar 23 | Nov 9 | 231 days |
| Optimistic | Mar 5 | Nov 1 | 241 days |
| Aggressive (risky) | Feb 4 | Oct 26 | 264 days |
Not very — frost dates can vary by ±71 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 shorter here (about 2.9 days per decade). Use the "Conservative" dates and choose fast-maturing varieties.
Gardening Difficulty Score
San Luis Obispo County presents some gardening challenges. Choose adapted varieties and plan around frost dates.
Local Gardening Help in San Luis Obispo 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 San Luis Obispo County's climate and soil.
County Extension Office
San Luis Obispo County University of California Cooperative Extension Extension Office
Phone: 530-750-1200
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 San Luis Obispo County
Finding local nurseries & garden centers in San Luis Obispo County
Why Buy Local
Local nurseries carry plants that are proven to grow in your area. Staff can give you advice specific to San Luis Obispo 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 San Luis Obispo County CA" or "garden center San Luis Obispo 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 San Luis Obispo County CA" or check your extension office and local parks department. Facebook groups like "San Luis Obispo County Gardeners" or "California Gardening" are also excellent for local advice and plant swaps.
What to Plant After Your Harvest
After your first crops finish, use the remaining frost-free days to grow a second round.
Show 6 more succession options
Sunlight & Day Length
Monthly daylight hours and peak sun — critical for onion varieties, photoperiod-sensitive plants, and solar garden planning.
Longest Day
14.4 hours
Summer solstice daylight
Shortest Day
9.6 hours
Winter solstice daylight
Peak Sun Hours
13.4 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: Day-neutral onion varieties like Candy, Cabernet, and Sierra Blanca perform best in your day-length range.
View detailed monthly data
| Month | Daylight Hours | Peak Sun Hours | Day Length |
|---|---|---|---|
| January | 9.9 hr | 5.9 hr | Short day |
| February | 10.7 hr | 6.6 hr | Short day |
| March | 11.7 hr | 7.6 hr | Short day |
| April | 12.9 hr | 9.4 hr | Neutral |
| May | 13.9 hr | 10.9 hr | Neutral |
| June | 14.4 hr | 13 hr | Long day |
| July | 14.2 hr | 13.4 hr | Long day |
| August | 13.3 hr | 11.5 hr | Neutral |
| September | 12.2 hr | 10.2 hr | Neutral |
| October | 11.1 hr | 8.4 hr | Short day |
| November | 10.1 hr | 6.1 hr | Short day |
| December | 9.6 hr | 5.4 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 Apr through Nov.
Best Month to Compost
May
Microbial activity peaks when soil is warm.
Active Composting
9 months
Nearly year-round composting.
View detailed monthly data
| Month | Soil 4" Deep | Soil 8" Deep | Compost Activity | Time to Finish |
|---|---|---|---|---|
| Jan | 47°F | 54°F | 🐢 Slow | ~24 weeks |
| Feb | 48°F | 53°F | 🐢 Slow | ~24 weeks |
| Mar | 53°F | 57°F | ♻️ Active | ~14 weeks |
| Apr | 63°F | 61°F | ♻️ Active | ~14 weeks |
| May | 71°F | 70°F | 🔥 Peak | ~8 weeks |
| Jun | 80°F | 78°F | 🔥 Peak | ~8 weeks |
| Jul | 90°F | 85°F | 🔥 Peak | ~8 weeks |
| Aug | 89°F | 87°F | 🔥 Peak | ~8 weeks |
| Sep | 83°F | 83°F | 🔥 Peak | ~8 weeks |
| Oct | 75°F | 75°F | 🔥 Peak | ~8 weeks |
| Nov | 62°F | 67°F | ♻️ Active | ~14 weeks |
| Dec | 50°F | 57°F | 🐢 Slow | ~24 weeks |
Highlighted rows = soil 60°F+ (safe for warm-season transplants). Compost finishes fastest during peak activity months.
Pest & Disease Pressure in San Luis Obispo County
Computed from local climate patterns — warmer, humid conditions increase pest generations and fungal disease risk.
Insect Pest Pressure
High — expect multiple pest generations. Preventative measures essential.
Disease Risk
Low disease risk — dry conditions reduce fungal problems.
Seasonal Risk
View 6 common pests in your area
| Pest | Risk Level | Peak Months |
|---|---|---|
| Aphids | High | Feb, Mar, Apr, May, Jun, Jul, Aug, Sep, Oct, Nov |
| Whiteflies | High | Apr, May, Jun, Jul, Aug, Sep, Oct, Nov |
| Spider mites | High | May, Jun, Jul, Aug, Sep, Oct |
| Fire ants | High | Mar, Apr, May, Jun, Jul, Aug, Sep, Oct, Nov |
| Thrips | Moderate | Apr, May, Jun, Jul, Aug |
| Leaf miners | Low | Mar, Apr, May, Jun |
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 San Luis Obispo County
Cover crops protect bare soil, fix nitrogen, suppress weeds, and improve soil structure — with county-specific planting dates.
Spring Cover Crops (4 options) — Build soil before the main growing season
| Crop | Plant By | Terminate | N-Fixing | Soil Benefit |
|---|---|---|---|---|
| Buckwheat | Mar 31 | Sep 7 | — | Rapid growth, attracts pollinators, suppresses weeds |
| Cowpeas (southern peas) | Apr 1 | Sep 14 | ✓ Yes | Excellent nitrogen fixer for warm climates, edible |
| Sorghum-sudan grass | Mar 31 | Sep 14 | — | Massive biomass, breaks compaction, suppresses nematodes |
| White clover | Feb 25 | Aug 31 | ✓ 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 | Apr 20 | Oct 12 | — | Deep roots break compaction, attract pollinators and beneficial insects |
Fall Cover Crops (4 options) — Plant after harvest to protect soil over winter
| Crop | Plant By | Terminate | N-Fixing | Soil Benefit |
|---|---|---|---|---|
| Austrian winter peas | Sep 13 | Mar 9 | ✓ Yes | Fixes nitrogen, good for heavy clay soils |
| Crimson clover | Sep 16 | Mar 2 | ✓ Yes | Fixes nitrogen, attracts pollinators in spring |
| Daikon radish | Sep 18 | Mar 9 | — | Deep taproot breaks compaction, excellent for clay soils |
| Hairy vetch | Aug 16 | Mar 2 | ✓ Yes | Excellent nitrogen fixer, good for depleted soils |
Wind & Microclimate
Wind dries soil, stresses plants, and affects frost patterns. Understanding your exposure helps with garden placement.
Seasonal Wind Speed
Spring: 11 mph Summer: 11 mph
Fall: 8 mph Winter: 8 mph
Prevailing wind: W. Moderate wind — consider a temporary windbreak for young seedlings.
Windbreak Benefit
4.8/10
Moderately beneficial — a simple fence or trellis can protect delicate crops from wind stress.
Frost Pocket Risk
Moderate
Some terrain variation (826 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
9,220 gal
Per 1,000 sq ft of roof area (at 80% collection efficiency)
Recommended Setup
8 rain barrels (55 gal each)
For a typical 500 sq ft garden. Serious collectors: consider a 2,500 gal tank.
Legal Status
Unrestricted
Rainwater harvesting is fully legal in your state with no restrictions.
Best Collection Months
Jan, Feb, Mar, Dec
Highest rainfall months — your barrels will fill up quickly during these months.
Months to Draw From Storage
May, Jun, Jul, Aug, Sep, Oct
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 18.5 inches of rain per year
- A 1,000 sq ft roof can collect roughly 9,220 gallons annually
- Rainwater harvesting is fully legal in your state
- In your dry climate, every drop counts — consider a larger cistern system
- Position collection tanks in shade to reduce evaporation and algae growth
Soil & Growing Conditions in San Luis Obispo County
Soil Type
Loam
Soil pH 6.6–7.8 · Well Drained drainage
Native soil is well-suited to most vegetables and herbs with regular compost additions.
Watering Needs
Drought stress: 7.5/10
High drought stress. Consistent irrigation is essential — consider drip systems, heavy mulch, and drought-tolerant varieties.
Season Tips
231-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 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
Reduce heat stress and sun scorch in hot climates with UV-stabilized shade cloth.
Test your soil pH, nitrogen, phosphorus, and potassium levels before planting.
Get instant, accurate soil pH readings to fine-tune your amendments.
🥬 Vegetables to Grow in San Luis Obispo County
106 vegetables that grow well in Zone 10a with planting dates for San Luis Obispo County.
Show all 106 vegetables with planting dates
| Plant | Start Indoors | Direct Sow | Transplant | Harvest | Days to Maturity |
|---|---|---|---|---|---|
| Acorn Squash | Feb 23 | Mar 23 | Mar 30 | Jun 22 – Jul 27 | 80–100 |
| Amaranth | Feb 9 | Mar 23 | Mar 30 | Jun 29 – Aug 17 | 90–120 |
| Artichoke | — | — | Apr 6 | Aug 10 – Oct 19 | 120–180 |
| Arugula | Feb 23 | Mar 2 | Mar 23 | Apr 27 – Jun 29 | 30–50 |
| Asparagus | — | — | Apr 6 | — | 730–1095 |
| Beets | — | Mar 2 | — | Apr 27 – May 25 | 50–70 |
| Belgian Endive | Feb 23 | Mar 2 | Mar 23 | Jul 13 – Sep 7 | 110–150 |
| Bitter Melon | Feb 9 | Mar 23 | Mar 30 | Jun 1 – Jul 13 | 60–90 |
| Black Beans | — | Mar 30 | — | Jun 29 – Aug 17 | 90–120 |
| Bok Choy | Feb 23 | Mar 2 | Mar 23 | May 4 – Jun 8 | 40–60 |
| Broccoli | Feb 23 | Mar 2 | Mar 23 | May 25 – Jul 6 | 60–90 |
| Broccoli Rabe | Feb 23 | Mar 2 | Mar 23 | May 4 – Jun 8 | 40–60 |
| Brussels Sprouts | Feb 23 | Mar 2 | Mar 23 | Jun 22 – Aug 17 | 90–130 |
| Butternut Squash | Feb 23 | Mar 23 | Mar 30 | Jun 29 – Aug 3 | 85–110 |
| Cabbage | Feb 23 | Mar 2 | Mar 23 | May 25 – Jul 20 | 60–100 |
| Calabash | Feb 9 | Mar 23 | Mar 30 | Jun 22 – Aug 17 | 80–120 |
| Cardoon | — | — | Apr 6 | Aug 10 – Sep 21 | 120–150 |
| Carrots | — | Mar 2 | — | May 4 – Jun 8 | 60–80 |
| Cauliflower | Feb 23 | Mar 2 | Mar 23 | May 18 – Jul 20 | 55–100 |
| Celery | Feb 23 | Mar 2 | Mar 23 | Jun 15 – Aug 10 | 80–120 |
| Celtuce | Feb 23 | Mar 2 | Mar 23 | May 25 – Jul 6 | 60–90 |
| Chard | Feb 23 | Mar 2 | Mar 23 | May 18 – Jul 6 | 50–60 |
| Chayote | Feb 9 | Mar 23 | Mar 30 | Aug 3 – Oct 12 | 120–180 |
| Chickpeas | Feb 23 | Mar 2 | Mar 23 | Jun 15 – Jul 27 | 80–110 |
| Chicory | Feb 23 | Mar 2 | Mar 23 | May 25 – Jul 6 | 60–85 |
| Chinese Cabbage | Feb 23 | Mar 2 | Mar 23 | May 18 – Jun 15 | 50–70 |
| Christmas Lima Beans | Feb 9 | Mar 23 | Mar 30 | Jun 22 – Jul 27 | 80–100 |
| Collard Greens | Feb 23 | Mar 2 | Mar 23 | May 18 – Jul 20 | 55–75 |
| Corn | — | Mar 30 | — | Jun 1 – Jul 27 | 60–100 |
| Cowpeas | — | Mar 30 | — | Jun 1 – Jul 13 | 60–90 |
| Cress | Feb 23 | Mar 2 | Mar 23 | Apr 6 – Apr 27 | 14–21 |
| Crookneck Squash | Feb 23 | Mar 23 | Mar 30 | May 18 – Jun 15 | 45–60 |
| Cucumber | Feb 23 | Mar 23 | Mar 30 | May 25 – Jul 20 | 50–70 |
| Daikon | — | Mar 2 | — | Apr 27 – May 25 | 50–70 |
| Delicata Squash | Feb 23 | Mar 23 | Mar 30 | Jun 22 – Jul 27 | 80–100 |
| Edamame | — | Mar 30 | — | Jun 15 – Jul 27 | 75–100 |
| Eggplant | Feb 9 | Mar 23 | Mar 30 | Jun 8 – Aug 10 | 65–85 |
| Endive | Feb 23 | Mar 2 | Mar 23 | May 11 – Jun 15 | 45–65 |
| Escarole | Feb 23 | Mar 2 | Mar 23 | May 18 – Jun 15 | 50–70 |
| Fava Beans | Feb 23 | Mar 2 | Mar 23 | Jun 8 – Jul 20 | 75–100 |
| Fennel | Feb 9 | Mar 23 | Mar 30 | Jun 1 – Jul 13 | 60–90 |
| Ginger | Feb 9 | Mar 23 | Mar 30 | Nov 30 – Feb 8 | 240–300 |
| Green Beans | — | Mar 30 | — | May 25 – Jul 20 | 50–65 |
| Hot Peppers | Feb 9 | Mar 23 | Mar 30 | Jun 8 – Sep 14 | 70–120 |
| Hubbard Squash | Feb 23 | Mar 23 | Mar 30 | Jul 13 – Aug 17 | 100–120 |
| Jicama | Feb 9 | Mar 23 | Mar 30 | Aug 3 – Oct 12 | 120–180 |
| Kabocha | Feb 23 | Mar 23 | Mar 30 | Jun 29 – Jul 27 | 85–100 |
| Kai Lan | Feb 23 | Mar 2 | Mar 23 | May 11 – Jun 8 | 45–60 |
| Kale | Feb 23 | Mar 2 | Mar 23 | May 18 – Jul 13 | 50–70 |
| Kidney Beans | — | Mar 30 | — | Jun 29 – Aug 3 | 85–110 |
| Kohlrabi | Feb 23 | Mar 2 | Mar 23 | May 11 – Jun 15 | 45–65 |
| Komatsuna | Feb 23 | Mar 2 | Mar 23 | Apr 27 – Jun 1 | 35–50 |
| Leeks | Feb 23 | Mar 2 | Mar 23 | Jun 22 – Sep 7 | 90–150 |
| Lentils | Feb 23 | Mar 2 | Mar 23 | Jun 15 – Jul 27 | 80–110 |
| Lettuce | Feb 23 | Mar 2 | Mar 23 | Apr 27 – Jul 6 | 30–60 |
| Lima Beans | — | Mar 30 | — | Jun 1 – Jul 13 | 60–90 |
| Loofah | Feb 9 | Mar 23 | Mar 30 | Jul 13 – Sep 14 | 100–150 |
| Luffa | Feb 9 | Mar 23 | Mar 30 | Jun 29 – Sep 14 | 90–150 |
| Mache | Feb 23 | Mar 2 | Mar 23 | May 4 – Jun 8 | 40–60 |
| Malabar Spinach | Feb 9 | Mar 23 | Mar 30 | May 25 – Jun 22 | 55–70 |
| Melon | Feb 23 | Mar 23 | Mar 30 | Jun 8 – Jul 27 | 70–100 |
| Microgreens | Feb 23 | Mar 2 | Mar 23 | Mar 30 – Apr 27 | 7–21 |
| Mizuna | Feb 23 | Mar 2 | Mar 23 | Apr 27 – May 25 | 30–45 |
| Mustard Greens | Feb 23 | Mar 2 | Mar 23 | Apr 27 – Jun 29 | 30–50 |
| Napa Cabbage | Feb 23 | Mar 2 | Mar 23 | May 18 – Jun 22 | 55–75 |
| New Zealand Spinach | Feb 9 | Mar 23 | Mar 30 | May 25 – Jun 22 | 55–70 |
| Okra | Feb 9 | Mar 23 | Mar 30 | May 25 – Jul 20 | 50–65 |
| Onion | Feb 23 | Mar 2 | Mar 23 | Jun 22 – Aug 10 | 90–120 |
| Pac Choi | Feb 23 | Mar 2 | Mar 23 | May 4 – Jun 1 | 40–55 |
| Patty Pan Squash | Feb 23 | Mar 23 | Mar 30 | May 18 – Jun 15 | 45–60 |
| Peas | Feb 23 | Mar 2 | Mar 23 | May 18 – Jul 13 | 55–70 |
| Peppers | Feb 9 | Mar 23 | Mar 30 | Jun 1 – Aug 10 | 60–90 |
| Pole Beans | Feb 9 | Mar 23 | Mar 30 | May 25 – Jul 20 | 55–70 |
| Potatoes | Feb 9 | Mar 23 | Mar 30 | Jun 8 – Aug 17 | 70–120 |
| Pumpkin | Feb 23 | Mar 23 | Mar 30 | Jun 29 – Aug 17 | 85–120 |
| Purslane | Feb 23 | Mar 2 | Mar 23 | May 4 – Jun 8 | 40–60 |
| Radicchio | Feb 23 | Mar 2 | Mar 23 | May 25 – Jun 29 | 60–80 |
| Radish | — | Mar 2 | — | Mar 30 – Apr 20 | 22–35 |
| Romanesco | Feb 23 | Mar 2 | Mar 23 | Jun 8 – Jul 20 | 75–100 |
| Savoy Cabbage | Feb 23 | Mar 2 | Mar 23 | Jun 1 – Jul 27 | 70–110 |
| Scallions | Feb 23 | Mar 2 | Mar 23 | May 18 – Jun 15 | 50–70 |
| Scarlet Runner Beans | Feb 9 | Mar 23 | Mar 30 | Jun 1 – Jul 6 | 60–80 |
| Shallot | Feb 23 | Mar 2 | Mar 23 | Jun 22 – Aug 10 | 90–120 |
| Shiso | Feb 9 | Mar 30 | Mar 30 | May 25 – Jul 20 | 50–70 |
| Snap Peas | Feb 9 | Mar 23 | Mar 30 | May 25 – Jul 20 | 55–70 |
| Snow Peas | Feb 23 | Mar 2 | Mar 23 | May 18 – Jul 13 | 50–65 |
| Soybeans | — | Mar 30 | — | Jun 22 – Aug 17 | 80–120 |
| Spaghetti Squash | Feb 23 | Mar 23 | Mar 30 | Jun 29 – Jul 27 | 85–100 |
| Spinach | Feb 23 | Mar 2 | Mar 23 | Apr 27 – Jun 29 | 35–50 |
| Squash (Summer) | Feb 23 | Mar 23 | Mar 30 | May 18 – Jul 20 | 45–65 |
| Squash (Winter) | Feb 23 | Mar 23 | Mar 30 | Jun 22 – Aug 17 | 80–120 |
| Sunflower | Feb 9 | Mar 23 | Mar 30 | Jun 8 – Jul 27 | 70–100 |
| Sweet Corn | — | Mar 30 | — | Jun 1 – Jul 13 | 60–90 |
| Sweet Potatoes | Feb 9 | Mar 23 | Mar 30 | Jun 29 – Aug 17 | 90–120 |
| Tatsoi | Feb 23 | Mar 2 | Mar 23 | Apr 27 – Jun 1 | 35–50 |
| Tomatillo | Feb 9 | Mar 23 | Mar 30 | Jun 1 – Aug 10 | 60–85 |
| Tomatoes | Feb 9 | Mar 23 | Mar 30 | Jun 1 – Aug 10 | 60–85 |
| Turmeric | Feb 9 | Mar 23 | Mar 30 | Nov 30 – Feb 8 | 240–300 |
| Turnip | — | Mar 2 | — | Apr 13 – May 18 | 40–60 |
| Watercress | Feb 23 | Mar 2 | Mar 23 | May 4 – Jun 8 | 40–60 |
| Watermelon | Feb 23 | Mar 23 | Mar 30 | Jun 8 – Jul 27 | 70–100 |
| Wax Beans | — | Mar 30 | — | May 25 – Jul 20 | 50–65 |
| Winter Melon | Feb 9 | Mar 23 | Mar 30 | Jun 29 – Aug 17 | 90–120 |
| Yam | Feb 9 | Mar 23 | Mar 30 | Sep 28 – Mar 15 | 180–330 |
| Yard Long Beans | Feb 9 | Mar 23 | Mar 30 | May 25 – Jul 6 | 55–80 |
| Zucchini | Feb 23 | Mar 23 | Mar 30 | May 18 – Jul 13 | 45–60 |
🍓 Fruits to Grow in San Luis Obispo County
16 fruits that grow well in Zone 10a with planting dates for San Luis Obispo County.
Show all 16 fruits with planting dates
| Plant | Start Indoors | Direct Sow | Transplant | Harvest | Days to Maturity |
|---|---|---|---|---|---|
| Alpine Strawberries | — | — | Apr 6 | Jul 6 – Oct 19 | 90–180 |
| Blackberries | — | — | Apr 6 | — | 365–730 |
| Boysenberries | — | — | Apr 6 | — | 365–730 |
| Cantaloupe | — | — | Apr 6 | Jun 15 – Jul 20 | 70–90 |
| Che Fruit | — | — | Apr 6 | — | 1095–1825 |
| Dragon Fruit | — | — | Apr 6 | — | 365–730 |
| Figs | — | — | Apr 6 | — | 730–1825 |
| Goji Berries | — | — | Apr 6 | — | 730–1095 |
| Grapes | — | — | Apr 6 | — | 730–1095 |
| Ground Cherry | — | — | Apr 6 | Jun 15 – Aug 10 | 65–80 |
| Guava | — | — | Apr 6 | — | 365–730 |
| Honeydew | — | — | Apr 6 | Jun 29 – Aug 10 | 80–110 |
| Loquat | — | — | Apr 6 | — | 730–1825 |
| Passion Fruit | — | — | Apr 6 | — | 365–545 |
| Pomegranate | — | — | Apr 6 | — | 730–1095 |
| Strawberries | — | — | Apr 6 | Jul 6 – Apr 5 | 90–365 |
🌿 Herbs to Grow in San Luis Obispo County
23 herbs that grow well in Zone 10a with planting dates for San Luis Obispo County.
Show all 23 herbs with planting dates
| Plant | Start Indoors | Direct Sow | Transplant | Harvest | Days to Maturity |
|---|---|---|---|---|---|
| Anise | Feb 23 | Mar 2 | Mar 16 | Jun 15 – Aug 31 | 90–120 |
| Basil | Feb 9 | Mar 30 | Mar 30 | May 25 – Jul 27 | 50–75 |
| Borage | Feb 23 | Mar 2 | Mar 16 | May 11 – Jun 29 | 50–60 |
| Chervil | Feb 23 | Mar 2 | Mar 16 | Apr 27 – Jun 29 | 40–60 |
| Chives | — | — | Mar 30 | Jun 1 – Aug 10 | 60–90 |
| Cilantro | Feb 23 | Mar 2 | Mar 16 | Apr 27 – Jun 29 | 40–60 |
| Cumin | Feb 23 | Mar 2 | Mar 16 | Jun 29 – Aug 31 | 100–120 |
| Dill | Feb 23 | Mar 2 | Mar 16 | Apr 27 – Jun 29 | 40–60 |
| Epazote | Feb 9 | Mar 30 | Mar 30 | May 18 – Jul 13 | 45–60 |
| Fennel (herb) | Feb 23 | Mar 2 | Mar 16 | May 18 – Jul 27 | 60–90 |
| Garlic Chives | — | — | Mar 30 | Jun 1 – Aug 10 | 60–90 |
| Horehound | — | — | Mar 30 | Jun 15 – Aug 10 | 75–90 |
| Lemon Verbena | Feb 9 | Mar 30 | Mar 30 | Jun 1 – Aug 10 | 60–90 |
| Lemongrass | Feb 9 | Mar 30 | Mar 30 | Jun 15 – Sep 14 | 75–120 |
| Marjoram | — | — | Mar 30 | Jun 1 – Aug 10 | 60–90 |
| Mint | — | — | Mar 30 | Jun 1 – Aug 10 | 60–90 |
| Oregano | — | — | Mar 30 | Jun 1 – Aug 10 | 60–90 |
| Parsley | Feb 23 | Mar 2 | Mar 16 | May 18 – Jul 20 | 60–80 |
| Rosemary | — | — | Mar 30 | Jun 22 – Nov 9 | 80–180 |
| Sage | — | — | Mar 30 | Jun 15 – Aug 10 | 75–90 |
| Savory | — | — | Mar 30 | May 25 – Jul 20 | 50–70 |
| Stevia | Feb 9 | Mar 30 | Mar 30 | Jun 1 – Aug 10 | 60–90 |
| Thai Basil | Feb 9 | Mar 30 | Mar 30 | May 25 – Jul 27 | 50–75 |
Monthly Planting Guide for San Luis Obispo County
Gardening Guides & Resources
Helpful guides from The Ultimate Homestead to improve your garden in San Luis Obispo County.
Frequently Asked Questions
What planting zone is San Luis Obispo County, CA?
San Luis Obispo County is in USDA Hardiness Zone 10a. 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 San Luis Obispo County, CA?
Based on 31 years of NOAA weather station data, the median last spring frost in San Luis Obispo County falls around March 23. In 8 out of 10 years, last frost lands between February 4 and April 16 — a 71-day window of variability. Use April 16 as your conservative safe-to-plant date for frost-sensitive crops.
When is the first fall frost in San Luis Obispo County, CA?
The median first fall frost in San Luis Obispo County arrives around November 9. In cold years it can arrive as early as October 26; in mild years as late as December 1. Harvest or protect frost-sensitive crops — tomatoes, peppers, basil, squash — before this date.
How long is the growing season in San Luis Obispo County?
San Luis Obispo County has a frost-free growing season of approximately 231 days. This long season supports multiple succession plantings and warm-season crops that need extended heat, like sweet potatoes and melons. Climate records show the growing season is trending shorter by about 2.91 days per decade.
What is the soil like in San Luis Obispo County for gardening?
San Luis Obispo County has predominantly Loam soil with a pH range of 6.6–7.8 and Well Drained drainage. Most vegetables and herbs grow well with standard composting and seasonal soil amendment.
What is grown commercially in San Luis Obispo County?
San Luis Obispo County has commercial agriculture that includes Almonds, Grapes, Dairy. These crops reflect the local climate and soil conditions — what succeeds commercially often translates well to home gardens in the same area.
Is San Luis Obispo County a good location for home gardening?
San Luis Obispo County scores 40/100 (Moderate) 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 San Luis Obispo County Garden Planner — Free
A 24-page printable planner built for San Luis Obispo County (Zone 10a). 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