Harmony, CA — Planting Guide for June
Free PDF, personalized for your town's frost dates & climate. Drop your email — we'll send the link.
June in San Luis Obispo County, California — your action list
Here's what deserves your attention in San Luis Obispo County, California this month. Everything below is tailored to Zone 10a and timed around your local frost dates.
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Start begonias, geraniums, and vinca (annual) under lights
Bottom-water once the first true leaves appear — it keeps stems dry and knocks back damping-off.
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Harvest basil, carrots, and cucumber as they ripen
Check every 1–2 days. Many of these get tough or go to seed if you wait too long.
Get ahead of July
- First harvests: basil, cucumber, and green beans
Harmony gardens in a dry climate (only 0" annual precipitation). Watering strategy matters more here than in most of the country — drip irrigation, deep mulching, and morning watering aren't optional, they're table stakes. The flip side: pest and disease pressure are far lower than in humid regions, and your soil temperatures climb fast in spring so you can plant heat-lovers earlier than the zone map suggests.
Soils trend Loam — the gold standard for vegetables. Add 2–3" of compost annually to maintain it and you'll outgrow most of your neighbors.
Harmony averages 28.3 drought weeks per year (US Drought Monitor, 2000–present, trend worsening). Treat irrigation as a year-round system, not a summer add-on.
🌡️ USDA Zone
10a (30°F to 35°F min)
❄️ Avg. Last Frost
March 23
🍂 Avg. First Frost
November 9
📅 Growing Season
231 days
🌧️ Climate
Arid 0.1" annual
💨 Wind
Moderate 6.4 mph avg
🥶 Frost Tier
Rare 70% frost-free years
🏜️ Drought
28.3 wk/yr trend worsening
📍 ZIP Codes
1 ZIP
Monthly Watering Calendar for Harmony
When you'll need to water your garden — based on average monthly rainfall vs. the ~1 inch/week most gardens need.
The practical takeaway: Watering by the calendar wastes water. Watering by the soil moisture (or by a free rain gauge) cuts your water use 30%+ and produces healthier roots. Harmony's 0" annual baseline is the starting point.
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.
Harmony 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 in Harmony
Monthly daylight hours and peak sun — critical for onion varieties, photoperiod-sensitive plants, and solar garden planning.
Quick context: Lettuce and cilantro "bolt" (go to seed) when days lengthen. Knowing your day-length curve helps you time spring plantings to harvest before the bolting trigger hits. Harmony's daylight ranges shape the planting calendar.
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 in Harmony
Monthly soil temps tell you when to plant warm-season crops, and when your compost pile is actively working.
What this means for you: Cold soil = stunted starts. A bean seed planted in 55°F soil rots before it germinates. Same seed in 65°F soil sprouts in 5 days. Harmony's soil temperature pattern shows you the difference month to month.
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 Harmony
Computed from local climate patterns — warmer, humid conditions increase pest generations and fungal disease risk.
What this means for you: Pest pressure scales with warmth and humidity. Hot humid Harmony 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
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 Harmony
Cover crops protect bare soil, fix nitrogen, suppress weeds, and improve soil structure — with planting dates calibrated for your area.
For new gardeners: Cover crops are the experienced gardener's secret weapon. Harmony's climate determines which species thrive: clover and vetch in mild winters, cereal rye and Austrian peas in cold ones.
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 in Harmony
What this means for you: Why care about wind? Above about 10 mph, evaporation jumps and pollinators struggle to land on flowers. Harmony's 6.4 mph average means you can plant tall crops without much support, but it doesn't mean ignore wind — a 20+ mph storm still snaps unstaked tomatoes.
Wind dries soil, stresses plants, and affects frost patterns. Understanding your exposure helps with garden placement.
Seasonal Wind Speed
Spring: 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 in Harmony
How much water you can collect, when to collect it, and what size system you need for your garden.
What this means for you: A gravity-fed rain barrel ($75) is the easy entry. A larger cistern ($500-1500) covers a whole growing season. Harmony's 0" annual rainfall determines whether the larger system is overkill or essential.
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
🥬 Vegetables to Grow in Harmony
105 vegetables matched to Zone 10a with planting dates calibrated for Harmony.
Show all 105 vegetables with dates
| Plant | Start Indoors | Direct Sow | Transplant | Fall Plant | 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 | Sep 14 | Apr 27 – Jun 29 | 30–50 |
| Asparagus | — | — | Apr 6 | — | — | 730–1095 |
| Beets | — | Mar 2 | — | Sep 14 | Apr 27 – May 25 | 50–70 |
| Belgian Endive | Feb 23 | Mar 2 | Mar 23 | Sep 14 | 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 | Sep 14 | May 4 – Jun 8 | 40–60 |
| Broccoli | Feb 23 | Mar 2 | Mar 23 | Sep 14 | May 25 – Jul 6 | 60–90 |
| Broccoli Rabe | Feb 23 | Mar 2 | Mar 23 | Sep 14 | May 4 – Jun 8 | 40–60 |
| Brussels Sprouts | Feb 23 | Mar 2 | Mar 23 | Sep 14 | 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 | Sep 14 | 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 | — | Sep 14 | May 4 – Jun 8 | 60–80 |
| Cauliflower | Feb 23 | Mar 2 | Mar 23 | Sep 14 | May 18 – Jul 20 | 55–100 |
| Celery | Feb 23 | Mar 2 | Mar 23 | Sep 14 | Jun 15 – Aug 10 | 80–120 |
| Celtuce | Feb 23 | Mar 2 | Mar 23 | Sep 14 | May 25 – Jul 6 | 60–90 |
| Chard | Feb 23 | Mar 2 | Mar 23 | Sep 14 | 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 | Sep 14 | Jun 15 – Jul 27 | 80–110 |
| Chicory | Feb 23 | Mar 2 | Mar 23 | Sep 14 | May 25 – Jul 6 | 60–85 |
| Chinese Cabbage | Feb 23 | Mar 2 | Mar 23 | Sep 14 | 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 | Sep 14 | 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 | Sep 14 | 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 | — | Sep 14 | 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 | Sep 14 | May 11 – Jun 15 | 45–65 |
| Escarole | Feb 23 | Mar 2 | Mar 23 | Sep 14 | May 18 – Jun 15 | 50–70 |
| Fava Beans | Feb 23 | Mar 2 | Mar 23 | Sep 14 | 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 | Sep 14 | May 11 – Jun 8 | 45–60 |
| Kale | Feb 23 | Mar 2 | Mar 23 | Sep 14 | May 18 – Jul 13 | 50–70 |
| Kidney Beans | — | Mar 30 | — | — | Jun 29 – Aug 3 | 85–110 |
| Kohlrabi | Feb 23 | Mar 2 | Mar 23 | Sep 14 | May 11 – Jun 15 | 45–65 |
| Komatsuna | Feb 23 | Mar 2 | Mar 23 | Sep 14 | Apr 27 – Jun 1 | 35–50 |
| Leeks | Feb 23 | Mar 2 | Mar 23 | Sep 14 | Jun 22 – Sep 7 | 90–150 |
| Lentils | Feb 23 | Mar 2 | Mar 23 | Sep 14 | Jun 15 – Jul 27 | 80–110 |
| Lettuce | Feb 23 | Mar 2 | Mar 23 | Sep 14 | 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 | Sep 14 | 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 | Sep 14 | Mar 30 – Apr 27 | 7–21 |
| Mizuna | Feb 23 | Mar 2 | Mar 23 | Sep 14 | Apr 27 – May 25 | 30–45 |
| Mustard Greens | Feb 23 | Mar 2 | Mar 23 | Sep 14 | Apr 27 – Jun 29 | 30–50 |
| Napa Cabbage | Feb 23 | Mar 2 | Mar 23 | Sep 14 | 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 | Sep 14 | Jun 22 – Aug 10 | 90–120 |
| Pac Choi | Feb 23 | Mar 2 | Mar 23 | Sep 14 | 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 | Sep 14 | 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 | Sep 14 | May 4 – Jun 8 | 40–60 |
| Radicchio | Feb 23 | Mar 2 | Mar 23 | Sep 14 | May 25 – Jun 29 | 60–80 |
| Radish | — | Mar 2 | — | Sep 14 | Mar 30 – Apr 20 | 22–35 |
| Romanesco | Feb 23 | Mar 2 | Mar 23 | Sep 14 | Jun 8 – Jul 20 | 75–100 |
| Savoy Cabbage | Feb 23 | Mar 2 | Mar 23 | Sep 14 | Jun 1 – Jul 27 | 70–110 |
| Scallions | Feb 23 | Mar 2 | Mar 23 | Sep 14 | 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 | Sep 14 | 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 | Sep 14 | 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 | Sep 14 | 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 |
| 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 | Sep 14 | 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 | — | Sep 14 | Apr 13 – May 18 | 40–60 |
| Watercress | Feb 23 | Mar 2 | Mar 23 | Sep 14 | 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 Harmony
16 fruits matched to Zone 10a with planting dates calibrated for Harmony.
Show all 16 fruits with dates
| Plant | Start Indoors | Direct Sow | Transplant | Fall Plant | 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 Harmony
23 herbs matched to Zone 10a with planting dates calibrated for Harmony.
Show all 23 herbs with dates
| Plant | Start Indoors | Direct Sow | Transplant | Fall Plant | Harvest | Days to Maturity |
|---|---|---|---|---|---|---|
| Anise | Feb 23 | Mar 2 | Mar 16 | Sep 14 | 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 | Sep 14 | May 11 – Jun 29 | 50–60 |
| Chervil | Feb 23 | Mar 2 | Mar 16 | Sep 14 | Apr 27 – Jun 29 | 40–60 |
| Chives | — | — | Mar 30 | — | Jun 1 – Aug 10 | 60–90 |
| Cilantro | Feb 23 | Mar 2 | Mar 16 | Sep 14 | Apr 27 – Jun 29 | 40–60 |
| Cumin | Feb 23 | Mar 2 | Mar 16 | Sep 14 | Jun 29 – Aug 31 | 100–120 |
| Dill | Feb 23 | Mar 2 | Mar 16 | Sep 14 | 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 | Sep 14 | 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 | Sep 14 | 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 |
🌸 Flowers to Grow in Harmony
31 flowers matched to Zone 10a with planting dates calibrated for Harmony.
Show all 31 flowers with dates
| Plant | Start Indoors | Direct Sow | Transplant | Fall Plant | Bloom | Days to Maturity |
|---|---|---|---|---|---|---|
| Ageratum | Feb 9 | Feb 16 | Feb 16 | — | Apr 13 – Oct 26 | 60–75 |
| Anemones | — | — | — | Sep 28 | Sep 28 – Oct 26 | 90–120 |
| Bachelor's Button | — | Jan 12 | Feb 9 | Aug 17 | Apr 6 – Jul 13 | 60–90 |
| Begonias | Jan 12 | — | Feb 9 | — | Apr 20 – Nov 16 | 70–90 |
| Calendula | — | Jan 12 | Feb 9 | Aug 3 | Mar 23 – Jun 29 | 50–70 |
| California Poppy | — | — | — | Aug 3 | Oct 12 – Feb 1 | 60–90 |
| Celosia | Feb 23 | Feb 16 | Feb 16 | — | Apr 20 – Nov 23 | 60–90 |
| Cosmos | Feb 23 | Feb 9 | Feb 9 | — | Apr 20 – Nov 2 | 60–90 |
| Dahlias | — | Mar 23 | Mar 23 | — | Jun 1 – Dec 28 | 70–120 |
| Daylily | Feb 9 | — | Feb 23 | — | May 4 – Nov 16 | 60–90 |
| Dianthus | Jan 26 | Jan 12 | Jan 12 | — | Mar 2 – Apr 20 | 60–80 |
| Freesia | — | — | — | Sep 28 | Sep 28 – Nov 2 | 84–112 |
| Gaillardia (Blanket Flower) | Feb 16 | Feb 23 | Feb 23 | — | May 4 – Nov 2 | 70–100 |
| Geraniums | Jan 12 | — | Feb 9 | — | Apr 20 – Nov 16 | 70–100 |
| Gladiolus | — | Mar 23 | Mar 23 | — | Jun 1 – Dec 28 | 70–100 |
| Impatiens | Jan 26 | — | Feb 16 | — | Apr 27 – Nov 9 | 60–75 |
| Larkspur | — | — | — | Sep 14 | Nov 23 – Feb 1 | 60–90 |
| Marigolds | Feb 16 | Feb 16 | Feb 16 | — | Apr 13 – Oct 19 | 50–70 |
| Nasturtium | Feb 23 | Feb 9 | Feb 9 | — | Apr 6 – Nov 2 | 55–65 |
| Pansy | — | Division | Feb 9 | Aug 3 | Mar 23 – Jun 1 | 70–90 |
| Petunia | Jan 26 | — | Feb 23 | — | May 4 – Nov 2 | 70–90 |
| Portulaca | Feb 23 | Feb 16 | Feb 16 | — | Apr 6 – Nov 9 | 50–70 |
| Ranunculus | — | — | — | Sep 28 | Sep 28 – Oct 26 | 90–120 |
| Roses | Jan 26 | — | Feb 23 | — | May 4 – Nov 16 | 90–180 |
| Salvia | Jan 26 | — | Feb 9 | — | Apr 20 – Nov 2 | 70–90 |
| Sedum (Stonecrop) | Feb 9 | — | Feb 23 | — | Jun 15 – Aug 10 | 60–90 |
| Snapdragon | — | Jan 12 | Feb 9 | Aug 3 | Apr 13 – Sep 7 | 70–100 |
| Sunflower | Mar 2 | Feb 9 | Feb 9 | — | May 4 – Nov 2 | 70–100 |
| Sweet Alyssum | — | Jan 12 | Feb 9 | Aug 17 | Mar 9 – Jun 1 | 45–60 |
| Vinca (Annual) | Jan 12 | — | Feb 9 | — | Apr 20 – Nov 30 | 70–90 |
| Zinnia | Feb 23 | Feb 9 | Feb 9 | — | Apr 20 – Nov 2 | 60–70 |
Monthly Planting Guide for Harmony
ZIP Codes in Harmony
Click any ZIP to see its specific frost, soil, and climate measurements (some ZIPs differ noticeably from the town aggregate):
Gardening Guides & Resources
Helpful guides from The Ultimate Homestead to improve your garden in San Luis Obispo County.
Your San Luis Obispo County Garden Planner — Free
A 22-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