Los Alamos County, NM — Planting Guide
Los Alamos County is in USDA Zone 6a. The average last spring frost is May 10 and the first fall frost is October 7, giving you a growing season of approximately 150 days.
At an elevation of 5,220 ft, Los Alamos County receives approximately 12.1 in of rainfall annually. Summer highs average 87°F with winter lows around 25°F. The predominant soil type is Sandy Loam.
Based on 31 years of NOAA climate station data, the last frost date here varies by 33 days year to year — ranging from April 23 in warm years to May 26 in cold years. The growing season is trending longer by about 2.28 days per decade. Los Alamos County scores 21/100 (Challenging) on the Microclimate Index.
🌡️ Zone
6a (-10°F to -5°F min)
❄️ Last Frost
May 10
🍂 First Frost
October 7
📅 Growing Season
150 days
⛰️ Elevation
5,220 ft
🌧️ Annual Rainfall
12.1 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 | 0.9 in | 3 days | — | None |
| Feb | 0.6 in | 2 days | — | None |
| Mar | 0.8 in | 2 days | 3.5 in | Critical |
| Apr | 0.4 in | 1 days | 3.9 in | Critical |
| May | 0.3 in | 1 days | 4 in | Critical |
| Jun | 0.4 in | 2 days | 3.9 in | Critical |
| Jul | 1.9 in | 6 days | 2.4 in | High |
| Aug | 2.4 in | 7 days | 1.9 in | High |
| Sep | 1.7 in | 5 days | 2.6 in | High |
| Oct | 1.1 in | 2 days | 3.2 in | Critical |
| Nov | 0.7 in | 1 days | — | None |
| Dec | 0.8 in | 2 days | — | None |
Annual total: 12 in. Gardens typically need ~1 inch of water per week during the growing season. Months marked "None" for extra water are outside the active growing season for your zone — most gardens are dormant and don't need irrigation during those months.
Los Alamos County Soil Profile
Soil Type
Sandy Loam
Soil pH
7-8.6
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 26 | Oct 23 | 150 days |
| Cautious | May 16 | Oct 11 | 148 days |
| Average year | May 10 | Oct 7 | 150 days |
| Optimistic | May 2 | Sep 28 | 149 days |
| Aggressive (risky) | Apr 23 | Sep 20 | 150 days |
Not very — frost dates can vary by ±33 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 2.3 days per decade). Spring is arriving earlier than it used to. Good news for gardeners.
Gardening Difficulty Score
Los Alamos County has challenging growing conditions. Season extension and careful variety selection are essential.
Local Gardening Help in Los Alamos 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 Los Alamos County's climate and soil.
County Extension Office
Los Alamos County New Mexico State University Extension Extension Office
Phone: 575-646-3015
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 Los Alamos County
Finding local nurseries & garden centers in Los Alamos County
Why Buy Local
Local nurseries carry plants that are proven to grow in your area. Staff can give you advice specific to Los Alamos 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 Los Alamos County NM" or "garden center Los Alamos 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 Los Alamos County NM" or check your extension office and local parks department. Facebook groups like "Los Alamos County Gardeners" or "New Mexico 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
13.3 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 | 9.8 hr | 7.1 hr | Short day |
| February | 10.7 hr | 8.2 hr | Short day |
| March | 11.7 hr | 8.7 hr | Short day |
| April | 12.9 hr | 10.5 hr | Neutral |
| May | 13.9 hr | 12.3 hr | Neutral |
| June | 14.4 hr | 13.3 hr | Long day |
| July | 14.2 hr | 10.7 hr | Long day |
| August | 13.4 hr | 9.8 hr | Neutral |
| September | 12.2 hr | 9.4 hr | Neutral |
| October | 11.1 hr | 9 hr | Short day |
| November | 10.1 hr | 7.4 hr | Short day |
| December | 9.6 hr | 6.9 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 Jul through Sep.
Best Month to Compost
Jul
Microbial activity peaks when soil is warm.
Active Composting
4 months
Short season — insulate pile or use indoor vermicomposting.
View detailed monthly data
| Month | Soil 4" Deep | Soil 8" Deep | Compost Activity | Time to Finish |
|---|---|---|---|---|
| Jan | 17°F | 25°F | ❄️ Dormant | ~36 weeks |
| Feb | 16°F | 23°F | ❄️ Dormant | ~36 weeks |
| Mar | 27°F | 30°F | ❄️ Dormant | ~36 weeks |
| Apr | 38°F | 37°F | ❄️ Dormant | ~36 weeks |
| May | 49°F | 46°F | 🐢 Slow | ~24 weeks |
| Jun | 59°F | 55°F | ♻️ Active | ~14 weeks |
| Jul | 65°F | 60°F | 🔥 Peak | ~8 weeks |
| Aug | 67°F | 63°F | 🔥 Peak | ~8 weeks |
| Sep | 61°F | 61°F | ♻️ Active | ~14 weeks |
| Oct | 49°F | 52°F | 🐢 Slow | ~24 weeks |
| Nov | 34°F | 40°F | ❄️ Dormant | ~36 weeks |
| Dec | 22°F | 31°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 Los Alamos County
Computed from local climate patterns — warmer, humid conditions increase pest generations and fungal disease risk.
Insect Pest Pressure
Moderate — common pests appear but manageable with monitoring.
Disease Risk
Low disease risk — dry conditions reduce fungal problems.
Seasonal Risk
View 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 | Moderate | Jun, Jul, Aug, Sep |
Organic pest management tips
- Maintain healthy soil with regular compost additions to build natural pest resistance
- Practice crop rotation annually to break pest cycles
- Encourage beneficial insects with flowering herbs like dill, fennel, and yarrow
Cover Crops for Los Alamos County
Cover crops protect bare soil, fix nitrogen, suppress weeds, and improve soil structure — with county-specific planting dates.
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 2 | Apr 26 | ✓ Yes | Fixes nitrogen, good for heavy clay soils |
| Crimson clover | Jul 30 | Apr 26 | ✓ Yes | Fixes nitrogen, attracts pollinators in spring |
| Daikon radish | Aug 17 | Apr 26 | — | Deep taproot breaks compaction, excellent for clay soils |
| Hairy vetch | Jul 14 | Apr 26 | ✓ Yes | Excellent nitrogen fixer, good for depleted soils |
| Oats | Sep 8 | Apr 19 | — | Quick biomass, winterkills in cold zones — no spring tillage needed |
| Winter rye | Jul 7 | Apr 19 | — | Suppresses weeds, prevents erosion, breaks up compacted soil |
| Winter wheat | Jun 30 | Apr 19 | — | Erosion control, weed suppression, good biomass |
Spring Cover Crops (3 options) — Build soil before the main growing season
| Crop | Plant By | Terminate | N-Fixing | Soil Benefit |
|---|---|---|---|---|
| Buckwheat | May 21 | Aug 5 | — | Rapid growth, attracts pollinators, suppresses weeds |
| Sorghum-sudan grass | May 20 | Jul 29 | — | Massive biomass, breaks compaction, suppresses nematodes |
| White clover | Apr 9 | Aug 5 | ✓ 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 21 | Sep 16 | — | Deep roots break compaction, attract pollinators and beneficial insects |
Wind & Microclimate
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: 9 mph Winter: 12 mph
Prevailing wind: SW. Moderate wind — consider a temporary windbreak for young seedlings.
Windbreak Benefit
5.4/10
Moderately beneficial — a simple fence or trellis can protect delicate crops from wind stress.
Frost Pocket Risk
High
Hilly terrain with 1,187 ft of elevation range — cold air pools in low spots. Avoid planting frost-sensitive crops in valleys.
Rainwater Harvesting Potential
How much water you can collect, when to collect it, and what size system you need for your garden.
Annual Collection
5,980 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 2,000 gal tank.
Legal Status
Unrestricted
Rainwater harvesting is fully legal in your state with no restrictions.
Best Collection Months
Jul, Aug, Sep, Oct
Highest rainfall months — your barrels will fill up quickly during these months.
Months to Draw From Storage
Jan, Feb, Mar, Apr, May, Jun, Nov, Dec
Dry months when you'll rely on stored water — size your storage for this gap.
Rainwater collection tips for your area
- Your county receives approximately 12.0 inches of rain per year
- A 1,000 sq ft roof can collect roughly 5,980 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 Los Alamos County
Soil Type
Sandy Loam
Soil pH 7–8.6 · Excessively Drained drainage
Raised beds strongly recommended here — native soil drainage or texture limits in-ground options.
Watering Needs
Drought stress: 9.5/10
Very high drought stress. Irrigation is critical for garden success. Focus on water-efficient techniques and drought-adapted crops.
Season Tips
150-day frost-free season
Start warm-season crops indoors and focus on short-season varieties. Cold frames extend your season by 3–4 weeks in fall.
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
Retain moisture and nutrients in sandy soils with expanded vermiculite.
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 Los Alamos County
108 vegetables that grow well in Zone 6a with planting dates for Los Alamos County.
Show all 108 vegetables with planting dates
| Plant | Start Indoors | Direct Sow | Transplant | Harvest | Days to Maturity |
|---|---|---|---|---|---|
| Acorn Squash | Apr 5 | May 17 | May 24 | Aug 16 – Sep 20 | 80–100 |
| Amaranth | Mar 15 | May 17 | May 24 | Aug 23 – Oct 11 | 90–120 |
| Arugula | Apr 5 | Apr 26 | May 10 | Jun 14 – Aug 16 | 30–50 |
| Asparagus | — | — | May 24 | — | 730–1095 |
| Beets | — | Apr 26 | — | Jun 21 – Jul 19 | 50–70 |
| Belgian Endive | Apr 5 | Apr 26 | May 10 | Aug 30 – Oct 25 | 110–150 |
| Bitter Melon | Mar 15 | May 17 | May 24 | Jul 26 – Sep 6 | 60–90 |
| Black Beans | — | May 17 | — | Aug 16 – Oct 4 | 90–120 |
| Bok Choy | Apr 5 | Apr 26 | May 10 | Jun 21 – Jul 26 | 40–60 |
| Broccoli | Apr 5 | Apr 26 | May 10 | Jul 12 – Aug 23 | 60–90 |
| Broccoli Rabe | Apr 5 | Apr 26 | May 10 | Jun 21 – Jul 26 | 40–60 |
| Brussels Sprouts | Apr 5 | Apr 26 | May 10 | Aug 9 – Oct 4 | 90–130 |
| Butternut Squash | Apr 5 | May 17 | May 24 | Aug 23 – Sep 27 | 85–110 |
| Cabbage | Apr 5 | Apr 26 | May 10 | Jul 12 – Sep 6 | 60–100 |
| Calabash | Mar 15 | May 17 | May 24 | Aug 16 – Oct 11 | 80–120 |
| Carrots | — | Apr 26 | — | Jun 28 – Aug 2 | 60–80 |
| Cauliflower | Apr 5 | Apr 26 | May 10 | Jul 5 – Sep 6 | 55–100 |
| Celeriac | Apr 5 | Apr 26 | May 10 | Aug 23 – Sep 27 | 100–120 |
| Celery | Apr 5 | Apr 26 | May 10 | Aug 2 – Sep 27 | 80–120 |
| Celtuce | Apr 5 | Apr 26 | May 10 | Jul 12 – Aug 23 | 60–90 |
| Chard | Apr 5 | Apr 26 | May 10 | Jul 5 – Aug 23 | 50–60 |
| Chickpeas | Apr 5 | Apr 26 | May 10 | Aug 2 – Sep 13 | 80–110 |
| Chicory | Apr 5 | Apr 26 | May 10 | Jul 12 – Aug 23 | 60–85 |
| Chinese Cabbage | Apr 5 | Apr 26 | May 10 | Jul 5 – Aug 2 | 50–70 |
| Christmas Lima Beans | Mar 15 | May 17 | May 24 | Aug 16 – Sep 20 | 80–100 |
| Collard Greens | Apr 5 | Apr 26 | May 10 | Jul 5 – Sep 6 | 55–75 |
| Corn | — | May 17 | — | Jul 19 – Sep 13 | 60–100 |
| Cowpeas | — | May 17 | — | Jul 19 – Aug 30 | 60–90 |
| Cress | Apr 5 | Apr 26 | May 10 | May 24 – Jun 14 | 14–21 |
| Crookneck Squash | Apr 5 | May 17 | May 24 | Jul 12 – Aug 9 | 45–60 |
| Crosne | — | Apr 26 | — | Sep 27 – Nov 8 | 150–200 |
| Cucumber | Apr 5 | May 17 | May 24 | Jul 19 – Sep 13 | 50–70 |
| Daikon | — | Apr 26 | — | Jun 21 – Jul 19 | 50–70 |
| Delicata Squash | Apr 5 | May 17 | May 24 | Aug 16 – Sep 20 | 80–100 |
| Edamame | — | May 17 | — | Aug 2 – Sep 13 | 75–100 |
| Eggplant | Mar 1 | May 17 | May 24 | Aug 2 – Oct 4 | 65–85 |
| Endive | Apr 5 | Apr 26 | May 10 | Jun 28 – Aug 2 | 45–65 |
| Escarole | Apr 5 | Apr 26 | May 10 | Jul 5 – Aug 2 | 50–70 |
| Fava Beans | Apr 5 | Apr 26 | May 10 | Jul 26 – Sep 6 | 75–100 |
| Fennel | Mar 15 | May 17 | May 24 | Jul 26 – Sep 6 | 60–90 |
| Garlic | — | — | — | — | 90–240 |
| Green Beans | — | May 17 | — | Jul 12 – Sep 6 | 50–65 |
| Horseradish | — | — | May 24 | Sep 27 – Dec 6 | 120–180 |
| Hot Peppers | Mar 1 | May 17 | May 24 | Aug 2 – Nov 8 | 70–120 |
| Hubbard Squash | Apr 5 | May 17 | May 24 | Sep 6 – Oct 11 | 100–120 |
| Kabocha | Apr 5 | May 17 | May 24 | Aug 23 – Sep 20 | 85–100 |
| Kai Lan | Apr 5 | Apr 26 | May 10 | Jun 28 – Jul 26 | 45–60 |
| Kale | Apr 5 | Apr 26 | May 10 | Jul 5 – Aug 30 | 50–70 |
| Kidney Beans | — | May 17 | — | Aug 16 – Sep 20 | 85–110 |
| Kohlrabi | Apr 5 | Apr 26 | May 10 | Jun 28 – Aug 2 | 45–65 |
| Komatsuna | Apr 5 | Apr 26 | May 10 | Jun 14 – Jul 19 | 35–50 |
| Leeks | Apr 5 | Apr 26 | May 10 | Aug 9 – Oct 25 | 90–150 |
| Lentils | Apr 5 | Apr 26 | May 10 | Aug 2 – Sep 13 | 80–110 |
| Lettuce | Apr 5 | Apr 26 | May 10 | Jun 14 – Aug 23 | 30–60 |
| Lima Beans | — | May 17 | — | Jul 19 – Aug 30 | 60–90 |
| Loofah | Mar 15 | May 17 | May 24 | Sep 6 – Nov 8 | 100–150 |
| Luffa | Mar 15 | May 17 | May 24 | Aug 23 – Nov 8 | 90–150 |
| Mache | Apr 5 | Apr 26 | May 10 | Jun 21 – Jul 26 | 40–60 |
| Melon | Apr 5 | May 17 | May 24 | Aug 2 – Sep 20 | 70–100 |
| Microgreens | Apr 5 | Apr 26 | May 10 | May 17 – Jun 14 | 7–21 |
| Mitsuba | Apr 5 | Apr 26 | May 3 | Jun 28 – Aug 23 | 50–70 |
| Mizuna | Apr 5 | Apr 26 | May 10 | Jun 14 – Jul 12 | 30–45 |
| Mustard Greens | Apr 5 | Apr 26 | May 10 | Jun 14 – Aug 16 | 30–50 |
| Napa Cabbage | Apr 5 | Apr 26 | May 10 | Jul 5 – Aug 9 | 55–75 |
| New Zealand Spinach | Mar 15 | May 17 | May 24 | Jul 19 – Aug 16 | 55–70 |
| Okra | Mar 15 | May 17 | May 24 | Jul 19 – Sep 13 | 50–65 |
| Onion | Apr 5 | Apr 26 | May 10 | Aug 9 – Sep 27 | 90–120 |
| Pac Choi | Apr 5 | Apr 26 | May 10 | Jun 21 – Jul 19 | 40–55 |
| Parsnip | — | Apr 26 | — | Aug 9 – Sep 20 | 100–130 |
| Patty Pan Squash | Apr 5 | May 17 | May 24 | Jul 12 – Aug 9 | 45–60 |
| Peas | Apr 5 | Apr 26 | May 10 | Jul 5 – Aug 30 | 55–70 |
| Peppers | Mar 1 | May 17 | May 24 | Jul 26 – Oct 4 | 60–90 |
| Pole Beans | Mar 15 | May 17 | May 24 | Jul 19 – Sep 13 | 55–70 |
| Potatoes | Mar 15 | May 17 | May 24 | Aug 2 – Oct 11 | 70–120 |
| Pumpkin | Apr 5 | May 17 | May 24 | Aug 23 – Oct 11 | 85–120 |
| Purslane | Apr 5 | Apr 26 | May 10 | Jun 21 – Jul 26 | 40–60 |
| Radicchio | Apr 5 | Apr 26 | May 10 | Jul 12 – Aug 16 | 60–80 |
| Radish | — | Apr 26 | — | May 24 – Jun 14 | 22–35 |
| Rhubarb | — | — | May 31 | — | 365–730 |
| Romanesco | Apr 5 | Apr 26 | May 10 | Jul 26 – Sep 6 | 75–100 |
| Rutabaga | — | Apr 26 | — | Jul 19 – Aug 23 | 80–100 |
| Salsify | — | Apr 26 | — | Aug 9 – Sep 20 | 100–130 |
| Savoy Cabbage | Apr 5 | Apr 26 | May 10 | Jul 19 – Sep 13 | 70–110 |
| Scallions | Apr 5 | Apr 26 | May 10 | Jul 5 – Aug 2 | 50–70 |
| Scarlet Runner Beans | Mar 15 | May 17 | May 24 | Jul 26 – Aug 30 | 60–80 |
| Shallot | Apr 5 | Apr 26 | May 10 | Aug 9 – Sep 27 | 90–120 |
| Shiso | Mar 22 | May 17 | May 24 | Jul 19 – Sep 13 | 50–70 |
| Snap Peas | Mar 15 | May 17 | May 24 | Jul 19 – Sep 13 | 55–70 |
| Snow Peas | Apr 5 | Apr 26 | May 10 | Jul 5 – Aug 30 | 50–65 |
| Soybeans | — | May 17 | — | Aug 9 – Oct 4 | 80–120 |
| Spaghetti Squash | Apr 5 | May 17 | May 24 | Aug 23 – Sep 20 | 85–100 |
| Spinach | Apr 5 | Apr 26 | May 10 | Jun 14 – Aug 16 | 35–50 |
| Squash (Summer) | Apr 5 | May 17 | May 24 | Jul 12 – Sep 13 | 45–65 |
| Squash (Winter) | Apr 5 | May 17 | May 24 | Aug 16 – Oct 11 | 80–120 |
| Sunchoke | — | — | May 24 | Sep 13 – Nov 8 | 110–150 |
| Sunflower | Mar 15 | May 17 | May 24 | Aug 2 – Sep 20 | 70–100 |
| Sweet Corn | — | May 17 | — | Jul 19 – Aug 30 | 60–90 |
| Sweet Potatoes | Mar 15 | May 17 | May 24 | Aug 23 – Oct 11 | 90–120 |
| Tatsoi | Apr 5 | Apr 26 | May 10 | Jun 14 – Jul 19 | 35–50 |
| Tomatillo | Mar 15 | May 17 | May 24 | Jul 26 – Oct 4 | 60–85 |
| Tomatoes | Mar 15 | May 17 | May 24 | Jul 26 – Oct 4 | 60–85 |
| Turnip | — | Apr 26 | — | Jun 7 – Jul 12 | 40–60 |
| Watercress | Apr 5 | Apr 26 | May 10 | Jun 21 – Jul 26 | 40–60 |
| Watermelon | Apr 5 | May 17 | May 24 | Aug 2 – Sep 20 | 70–100 |
| Wax Beans | — | May 17 | — | Jul 12 – Sep 6 | 50–65 |
| Winter Melon | Mar 15 | May 17 | May 24 | Aug 23 – Oct 11 | 90–120 |
| Yard Long Beans | Mar 15 | May 17 | May 24 | Jul 19 – Aug 30 | 55–80 |
| Zucchini | Apr 5 | May 17 | May 24 | Jul 12 – Sep 6 | 45–60 |
🍓 Fruits to Grow in Los Alamos County
27 fruits that grow well in Zone 6a with planting dates for Los Alamos County.
Show all 27 fruits with planting dates
| Plant | Start Indoors | Direct Sow | Transplant | Harvest | Days to Maturity |
|---|---|---|---|---|---|
| Alpine Strawberries | — | — | May 31 | Aug 30 – Dec 13 | 90–180 |
| Aronia | — | — | May 31 | — | 730–1095 |
| Blackberries | — | — | May 31 | — | 365–730 |
| Blueberries | — | — | May 31 | — | 730–1095 |
| Boysenberries | — | — | May 31 | — | 365–730 |
| Cantaloupe | — | — | May 31 | Aug 9 – Sep 13 | 70–90 |
| Che Fruit | — | — | May 31 | — | 1095–1825 |
| Cranberries | — | — | May 31 | — | 730–1095 |
| Currants | — | — | May 31 | — | 730–1095 |
| Elderberries | — | — | May 31 | — | 730–1095 |
| Goji Berries | — | — | May 31 | — | 730–1095 |
| Gooseberries | — | — | May 31 | — | 730–1095 |
| Grapes | — | — | May 31 | — | 730–1095 |
| Ground Cherry | — | — | May 31 | Aug 9 – Oct 4 | 65–80 |
| Hardy Kiwi | — | — | May 31 | — | 1095–1825 |
| Haskaps | — | — | May 31 | — | 730–1095 |
| Honeydew | — | — | May 31 | Aug 23 – Oct 4 | 80–110 |
| Jostaberry | — | — | May 31 | — | 730–1095 |
| Lingonberries | — | — | May 31 | — | 730–1095 |
| Medlar | — | — | May 31 | — | 1095–1825 |
| Mulberries | — | — | May 31 | — | 730–1825 |
| Pawpaw | — | — | May 31 | — | 1095–2555 |
| Persimmon | — | — | May 31 | — | 1095–2555 |
| Quince | — | — | May 31 | — | 1095–1825 |
| Raspberries | — | — | May 31 | — | 365–730 |
| Serviceberries | — | — | May 31 | — | 730–1095 |
| Strawberries | — | — | May 31 | Aug 30 – Dec 13 | 90–365 |
🌿 Herbs to Grow in Los Alamos County
38 herbs that grow well in Zone 6a with planting dates for Los Alamos County.
Show all 38 herbs with planting dates
| Plant | Start Indoors | Direct Sow | Transplant | Harvest | Days to Maturity |
|---|---|---|---|---|---|
| Angelica | Apr 5 | Apr 26 | May 3 | — | 365–730 |
| Anise | Apr 5 | Apr 26 | May 3 | Aug 2 – Oct 18 | 90–120 |
| Basil | Mar 22 | May 17 | May 24 | Jul 19 – Sep 20 | 50–75 |
| Bee Balm | — | — | May 17 | Aug 16 – Nov 1 | 90–120 |
| Borage | Apr 5 | Apr 26 | May 3 | Jun 28 – Aug 16 | 50–60 |
| Caraway | Apr 5 | Apr 26 | May 3 | — | 365–450 |
| Catnip | — | — | May 17 | Jul 19 – Sep 20 | 60–80 |
| Chamomile | Apr 5 | Apr 26 | May 3 | Jul 5 – Sep 13 | 60–90 |
| Chervil | Apr 5 | Apr 26 | May 3 | Jun 14 – Aug 16 | 40–60 |
| Chives | — | — | May 17 | Jul 19 – Sep 27 | 60–90 |
| Cilantro | Apr 5 | Apr 26 | May 3 | Jun 14 – Aug 16 | 40–60 |
| Comfrey | — | — | May 17 | Jul 19 – Sep 27 | 60–90 |
| Cumin | Apr 5 | Apr 26 | May 3 | Aug 16 – Oct 18 | 100–120 |
| Dill | Apr 5 | Apr 26 | May 3 | Jun 14 – Aug 16 | 40–60 |
| Echinacea | — | — | May 17 | Sep 20 – Nov 29 | 120–180 |
| Epazote | Mar 22 | May 17 | May 24 | Jul 12 – Sep 6 | 45–60 |
| Fennel (herb) | Apr 5 | Apr 26 | May 3 | Jul 5 – Sep 13 | 60–90 |
| Feverfew | — | — | May 17 | Aug 16 – Nov 1 | 90–120 |
| Garlic Chives | — | — | May 17 | Jul 19 – Sep 27 | 60–90 |
| Horehound | — | — | May 17 | Aug 2 – Sep 27 | 75–90 |
| Hyssop | — | — | May 17 | Jul 26 – Sep 27 | 70–90 |
| Lavender | — | — | May 17 | Aug 16 – Nov 29 | 90–200 |
| Lemon Balm | — | — | May 17 | Jul 19 – Sep 6 | 60–70 |
| Lemon Thyme | — | — | May 17 | Jul 26 – Sep 27 | 70–90 |
| Lovage | — | — | May 17 | Jul 26 – Sep 27 | 70–90 |
| Marjoram | — | — | May 17 | Jul 19 – Sep 27 | 60–90 |
| Mint | — | — | May 17 | Jul 19 – Sep 27 | 60–90 |
| Oregano | — | — | May 17 | Jul 19 – Sep 27 | 60–90 |
| Parsley | Apr 5 | Apr 26 | May 3 | Jul 5 – Sep 6 | 60–80 |
| Rue | — | — | May 17 | Jul 26 – Sep 27 | 70–90 |
| Sage | — | — | May 17 | Aug 2 – Sep 27 | 75–90 |
| Savory | — | — | May 17 | Jul 12 – Sep 6 | 50–70 |
| Sorrel | Apr 5 | Apr 26 | May 3 | Jun 14 – Aug 16 | 40–60 |
| Tarragon | — | — | May 17 | Jul 19 – Sep 27 | 60–90 |
| Thai Basil | Mar 22 | May 17 | May 24 | Jul 19 – Sep 20 | 50–75 |
| Thyme | — | — | May 17 | Jul 26 – Sep 27 | 70–90 |
| Valerian | — | — | May 17 | Sep 20 – Nov 29 | 120–180 |
| Yarrow | — | — | May 17 | Aug 16 – Nov 1 | 90–120 |
Monthly Planting Guide for Los Alamos County
Gardening Guides & Resources
Helpful guides from The Ultimate Homestead to improve your garden in Los Alamos County.
Frequently Asked Questions
What planting zone is Los Alamos County, NM?
Los Alamos 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 Los Alamos County, NM?
Based on 31 years of NOAA weather station data, the median last spring frost in Los Alamos County falls around May 10. In 8 out of 10 years, last frost lands between April 23 and May 26 — a 33-day window of variability. Use May 26 as your conservative safe-to-plant date for frost-sensitive crops.
When is the first fall frost in Los Alamos County, NM?
The median first fall frost in Los Alamos County arrives around October 7. In cold years it can arrive as early as September 20; in mild years as late as October 23. Harvest or protect frost-sensitive crops — tomatoes, peppers, basil, squash — before this date.
How long is the growing season in Los Alamos County?
Los Alamos County has a frost-free growing season of approximately 150 days. This is enough time for most warm-season crops including tomatoes, peppers, and squash with proper timing. Climate records show the growing season is trending longer by about 2.28 days per decade.
What is the soil like in Los Alamos County for gardening?
Los Alamos County has predominantly Sandy Loam soil with a pH range of 7–8.6 and Excessively Drained drainage. The native soil conditions make raised beds a particularly good investment here — they let you control drainage and fertility independent of the ground soil.
What is grown commercially in Los Alamos County?
Los Alamos County has commercial agriculture that includes Hay, Cattle, Cotton, Pecans, Dairy. These crops reflect the local climate and soil conditions — what succeeds commercially often translates well to home gardens in the same area.
Is Los Alamos County a good location for home gardening?
Los Alamos County scores 21/100 (Challenging) on our Microclimate Index, which combines frost reliability, drought pressure, soil challenge, elevation risk, and long-term climate trend. Gardening here benefits from close attention to frost timing and season extension due to the challenging microclimate factors.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Los Alamos 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.
