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Costilla County, CO — Planting Guide

Costilla County, Colorado Zone 5b May

Your May gardening checklist

May is a pivotal month for Costilla County, Colorado gardens. Focus on these tasks first and you'll set up the rest of the season for success.

Avg. last frost June 8
Avg. first frost September 16
Soil temp (4") 43°F
Watering High
Pest pressure Low
Daylight 14 hrs
  1. Seed carrots, kale, and lettuce outdoors

    Sow every 2 weeks for a continuous harvest. A single big planting means a single big glut.

Get ahead of June
  • Transplants going out: basil, cucumber, and kale
  • Direct-sowing: basil, cucumber, and green beans
  • First harvests: radish, cress, and microgreens

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Costilla County is in USDA Zone 5b. The average last spring frost is June 8 and the first fall frost is September 16, giving you a growing season of approximately 100 days.

At an elevation of 5,598 ft, Costilla County receives approximately 21 in of rainfall annually. Summer highs average 86°F with winter lows around 11°F. The predominant soil type is Loam.

Based on 31 years of NOAA climate station data, the last frost date here varies by 26 days year to year — ranging from May 24 in warm years to June 19 in cold years. Costilla County scores 49/100 (Moderate) on the Microclimate Index.

🌡️ Zone

5b (°F to °F min)

❄️ Last Frost

June 8

🍂 First Frost

September 16

📅 Growing Season

100 days

⛰️ Elevation

5,598 ft

🌧️ Annual Rainfall

21 in

Costilla County, CO Short season
100 days
Last Spring Frost June 8
100 growing days
First Fall Frost September 16

Monthly Watering Calendar

When you'll need to water your garden — based on average monthly rainfall vs. the ~1 inch/week most gardens need.

1"/wk 0" 1.3" 2.5" 3.8" 5" Jan 1.3" Feb 1.3" Mar 1.9" +2.3" Apr 2" +1.8" May 2.5" +3" Jun 1.3" +2.3" Jul 2" +1.8" Aug 2.5" +2.6" Sep 1.7" +2.4" Oct 1.9" Nov 1.3" Dec 1.4"
Rainfall sufficient Supplemental water needed Heavy watering required - - - 1"/week garden need
View detailed monthly data
MonthAvg RainfallRainy DaysExtra Water NeededWatering Effort
Jan 1.3 in 7 days None
Feb 1.3 in 5 days None
Mar 1.9 in 6 days None
Apr 2 in 7 days 2.3 in High
May 2.5 in 7 days 1.8 in High
Jun 1.3 in 4 days 3 in High
Jul 2 in 5 days 2.3 in High
Aug 2.5 in 7 days 1.8 in High
Sep 1.7 in 6 days 2.6 in High
Oct 1.9 in 5 days 2.4 in High
Nov 1.3 in 5 days None
Dec 1.4 in 6 days None

Annual total: 21.1 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.

Costilla County Soil Profile

Soil Type

Loam

Soil pH

6.2-8.3

Drainage

Well Drained

Frost Risk Probability

Based on 31 years of NOAA weather station data from 3 stations

Too early frost risk Safe to Plant Jun 8 → Sep 16 100 frost-free days Protect crops frost returns May Jun Jul Aug Sep Oct Safe: Jun 19 Protect by: Sep 29

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 19 Sep 29 102 days
Cautious Jun 13 Sep 21 100 days
Average year Jun 8 Sep 16 100 days
Optimistic May 30 Sep 11 104 days
Aggressive (risky) May 24 Sep 6 105 days
📊
How predictable are frost dates here?

Not very — frost dates can vary by ±26 days year-to-year. Use the "Conservative" row in the table below, and keep row covers handy for surprise late frosts.

⚠️
Is the growing season changing?

Slightly — seasons are trending a bit shorter (0.3 days/decade). Stay conservative with planting dates.

Gardening Difficulty Score

49 Moderate
Frost Timing Risk
10.0/10
Drought Risk
5.5/10
Soil Difficulty
1.0/10
Altitude Challenge
9.2/10
Climate Shift
1.3/10
Rainfall Challenge
3.6/10

Costilla County presents some gardening challenges. Choose adapted varieties and plan around frost dates.

Zone 5b Frost Countdown
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Loading...
Last Frost: Jun 8 First Frost: Sep 16

Local Gardening Help in Costilla 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 Costilla County's climate and soil.

County Extension Office

Costilla County Colorado State University Extension Extension Office

Phone: 970-491-6281

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.

Find Master Gardeners in CO →

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.

Request a Soil Test →

Services Available in Costilla County

Soil testing High-altitude gardening Water conservation Pest diagnostics
Finding local nurseries & garden centers in Costilla County

Why Buy Local

Local nurseries carry plants that are proven to grow in your area. Staff can give you advice specific to Costilla 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 Costilla County CO" or "garden center Costilla 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 Costilla County CO" or check your extension office and local parks department. Facebook groups like "Costilla County Gardeners" or "Colorado 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

14.6 hours

Summer solstice daylight

Shortest Day

9.4 hours

Winter solstice daylight

Peak Sun Hours

10 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.

14hr 12hr 3h 6h 10h 13h 16h Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Daylight hours (sunrise to sunset) Peak sun hours (direct sunlight after cloud cover) ▪ Gold zone = long day (14+ hr) ▪ Blue zone = short day (<12 hr)

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
MonthDaylight HoursPeak Sun HoursDay Length
January 9.7 hr 5.1 hr Short day
February 10.6 hr 6.4 hr Short day
March 11.7 hr 7.1 hr Short day
April 13 hr 7.5 hr Neutral
May 14 hr 8.8 hr Long day
June 14.6 hr 10 hr Long day
July 14.3 hr 9.6 hr Long day
August 13.4 hr 9.1 hr Neutral
September 12.2 hr 8.5 hr Neutral
October 11 hr 6.9 hr Short day
November 10 hr 5.5 hr Short day
December 9.4 hr 4.9 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 Aug.

Best Month to Compost

Jun

Microbial activity peaks when soil is warm.

Active Composting

4 months

Short season — insulate pile or use indoor vermicomposting.

60°F 70°F 20° 40° 60° 80° Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
4" depth 8" depth - - - 60°F (corn, beans) - - - 70°F (tomatoes, peppers)
View detailed monthly data
MonthSoil 4" DeepSoil 8" DeepCompost ActivityTime to Finish
Jan 6°F 17°F ❄️ Dormant ~36 weeks
Feb 9°F 15°F ❄️ Dormant ~36 weeks
Mar 17°F 18°F ❄️ Dormant ~36 weeks
Apr 28°F 29°F ❄️ Dormant ~36 weeks
May 43°F 38°F 🐢 Slow ~24 weeks
Jun 52°F 47°F ♻️ Active ~14 weeks
Jul 62°F 54°F ♻️ Active ~14 weeks
Aug 64°F 58°F ♻️ Active ~14 weeks
Sep 55°F 54°F ♻️ Active ~14 weeks
Oct 42°F 45°F 🐢 Slow ~24 weeks
Nov 26°F 33°F ❄️ Dormant ~36 weeks
Dec 17°F 22°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 Costilla County

Computed from local climate patterns — warmer, humid conditions increase pest generations and fungal disease risk.

Insect Pest Pressure

4 / 10

Moderate — common pests appear but manageable with monitoring.

Disease Risk

2.4 / 10

Low disease risk — dry conditions reduce fungal problems.

Seasonal Risk

Spring Low
Summer High
Fall Low
Winter Low
View 5 common pests in your area
PestRisk LevelPeak Months
Aphids Moderate May, Jun, Jul, Aug
Japanese beetles Moderate Jun, Jul, Aug
Squash bugs Moderate Jun, Jul, Aug
Tomato hornworms Low Jul, Aug
Cabbage loopers Low May, Jun, Jul, Aug
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 Costilla 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 8 Rapid growth, attracts pollinators, suppresses weeds
Sorghum-sudan grass Jun 10 Jul 15 Massive biomass, breaks compaction, suppresses nematodes
White clover May 14 Jul 15 ✓ 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 24 Sep 2 Deep roots break compaction, attract pollinators and beneficial insects
Fall Cover Crops (6 options) — Plant after harvest to protect soil over winter
Crop Plant By Terminate N-Fixing Soil Benefit
Austrian winter peas Jul 8 May 25 ✓ Yes Fixes nitrogen, good for heavy clay soils
Daikon radish Aug 3 May 18 Deep taproot breaks compaction, excellent for clay soils
Hairy vetch Jun 25 May 25 ✓ Yes Excellent nitrogen fixer, good for depleted soils
Oats Aug 9 May 25 Quick biomass, winterkills in cold zones — no spring tillage needed
Winter rye Jun 21 May 18 Suppresses weeds, prevents erosion, breaks up compacted soil
Winter wheat Jun 23 May 18 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: 14 mph   Summer: 12 mph

Fall: 13 mph   Winter: 15 mph

Prevailing wind: W. Windy area — plant a windbreak hedge on the W side of your garden.

Windbreak Benefit

7.1/10

Strongly recommended — a windbreak (fence, hedge, or row of tall crops like corn or sunflowers) will significantly improve garden yields.

Frost Pocket Risk

Moderate

Some terrain variation (794 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

10,516 gal

Per 1,000 sq ft of roof area (at 80% collection efficiency)

Recommended Setup

7 rain barrels (55 gal each)

For a typical 500 sq ft garden. Serious collectors: consider a 1,750 gal tank.

Legal Status

Limited

Your state has quantity limits on rainwater collection — check local regulations before installing large systems.

Best Collection Months

Apr, May, Jul, Aug

Highest rainfall months — your barrels will fill up quickly during these months.

Months to Draw From Storage

Feb, Jun, Nov

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 21.1 inches of rain per year
  • A 1,000 sq ft roof can collect roughly 10,516 gallons annually
  • Check CO state regulations — rainwater harvesting has quantity limits
  • Stock up on stored water before your dry season (Feb, Jun, Nov)
  • Use a first-flush diverter to keep roof debris out of your collection

Soil & Growing Conditions in Costilla County

Soil Type

Loam

Soil pH 6.2–8.3 · Excessively Drained drainage

Good candidate for raised beds to maximise drainage and extend the season.

Watering Needs

Drought stress: 5.5/10

Moderate drought pressure. Drip irrigation and mulching are highly recommended to maintain soil moisture through summer.

Season Tips

100-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.

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.

Instant PDF download. No spam, unsubscribe any time.

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Recommended for Your Garden

🧪
Soil Test Kit $12-25

Test your soil pH, nitrogen, phosphorus, and potassium levels before planting.

📏
Digital pH Meter $10-20

Get instant, accurate soil pH readings to fine-tune your amendments.

🍂
Organic Compost $8-30

Boost soil fertility and structure with rich, well-aged organic compost.

🥬 Vegetables to Grow in Costilla County

106 vegetables that grow well in Zone 5b with planting dates for Costilla County.

Show all 106 vegetables with planting dates
Plant Start Indoors Direct Sow Transplant Harvest Days to Maturity
Acorn Squash May 4 Jun 15 Jun 22 Sep 14 – Oct 19 80–100
Amaranth Apr 13 Jun 15 Jun 22 Sep 21 – Nov 9 90–120
Arugula May 4 May 25 Jun 8 Jul 13 – Sep 14 30–50
Asparagus Jun 22 730–1095
Beets May 25 Jul 20 – Aug 17 50–70
Belgian Endive May 4 May 25 Jun 8 Sep 28 – Nov 23 110–150
Bitter Melon Apr 13 Jun 15 Jun 22 Aug 24 – Oct 5 60–90
Black Beans Jun 15 Sep 14 – Nov 2 90–120
Bok Choy May 4 May 25 Jun 8 Jul 20 – Aug 24 40–60
Broccoli May 4 May 25 Jun 8 Aug 10 – Sep 21 60–90
Broccoli Rabe May 4 May 25 Jun 8 Jul 20 – Aug 24 40–60
Brussels Sprouts May 4 May 25 Jun 8 Sep 7 – Nov 2 90–130
Butternut Squash May 4 Jun 15 Jun 22 Sep 21 – Oct 26 85–110
Cabbage May 4 May 25 Jun 8 Aug 10 – Oct 5 60–100
Calabash Apr 13 Jun 15 Jun 22 Sep 14 – Nov 9 80–120
Carrots May 25 Jul 27 – Aug 31 60–80
Cauliflower May 4 May 25 Jun 8 Aug 3 – Oct 5 55–100
Celeriac May 4 May 25 Jun 8 Sep 21 – Oct 26 100–120
Celery May 4 May 25 Jun 8 Aug 31 – Oct 26 80–120
Celtuce May 4 May 25 Jun 8 Aug 10 – Sep 21 60–90
Chard May 4 May 25 Jun 8 Aug 3 – Sep 21 50–60
Chickpeas May 4 May 25 Jun 8 Aug 31 – Oct 12 80–110
Chicory May 4 May 25 Jun 8 Aug 10 – Sep 21 60–85
Chinese Cabbage May 4 May 25 Jun 8 Aug 3 – Aug 31 50–70
Christmas Lima Beans Apr 13 Jun 15 Jun 22 Sep 14 – Oct 19 80–100
Collard Greens May 4 May 25 Jun 8 Aug 3 – Oct 5 55–75
Corn Jun 15 Aug 17 – Oct 12 60–100
Cowpeas Jun 15 Aug 17 – Sep 28 60–90
Cress May 4 May 25 Jun 8 Jun 22 – Jul 13 14–21
Crookneck Squash May 4 Jun 15 Jun 22 Aug 10 – Sep 7 45–60
Crosne May 25 Oct 26 – Nov 9 150–200
Cucumber May 4 Jun 15 Jun 22 Aug 17 – Oct 12 50–70
Daikon May 25 Jul 20 – Aug 17 50–70
Delicata Squash May 4 Jun 15 Jun 22 Sep 14 – Oct 19 80–100
Edamame Jun 15 Aug 31 – Oct 12 75–100
Eggplant Mar 30 Jun 15 Jun 22 Aug 31 – Nov 2 65–85
Endive May 4 May 25 Jun 8 Jul 27 – Aug 31 45–65
Escarole May 4 May 25 Jun 8 Aug 3 – Aug 31 50–70
Fava Beans May 4 May 25 Jun 8 Aug 24 – Oct 5 75–100
Fennel Apr 13 Jun 15 Jun 22 Aug 24 – Oct 5 60–90
Garlic 90–240
Green Beans Jun 15 Aug 10 – Oct 5 50–65
Horseradish Jun 22 Oct 26 – Dec 7 120–180
Hot Peppers Mar 30 Jun 15 Jun 22 Aug 31 – Dec 7 70–120
Hubbard Squash May 4 Jun 15 Jun 22 Oct 5 – Nov 9 100–120
Kabocha May 4 Jun 15 Jun 22 Sep 21 – Oct 19 85–100
Kai Lan May 4 May 25 Jun 8 Jul 27 – Aug 24 45–60
Kale May 4 May 25 Jun 8 Aug 3 – Sep 28 50–70
Kidney Beans Jun 15 Sep 14 – Oct 19 85–110
Kohlrabi May 4 May 25 Jun 8 Jul 27 – Aug 31 45–65
Komatsuna May 4 May 25 Jun 8 Jul 13 – Aug 17 35–50
Leeks May 4 May 25 Jun 8 Sep 7 – Nov 23 90–150
Lentils May 4 May 25 Jun 8 Aug 31 – Oct 12 80–110
Lettuce May 4 May 25 Jun 8 Jul 13 – Sep 21 30–60
Lima Beans Jun 15 Aug 17 – Sep 28 60–90
Mache May 4 May 25 Jun 8 Jul 20 – Aug 24 40–60
Melon May 4 Jun 15 Jun 22 Aug 31 – Oct 19 70–100
Microgreens May 4 May 25 Jun 8 Jun 15 – Jul 13 7–21
Mitsuba May 4 May 25 Jun 1 Jul 27 – Sep 21 50–70
Mizuna May 4 May 25 Jun 8 Jul 13 – Aug 10 30–45
Mustard Greens May 4 May 25 Jun 8 Jul 13 – Sep 14 30–50
Napa Cabbage May 4 May 25 Jun 8 Aug 3 – Sep 7 55–75
New Zealand Spinach Apr 13 Jun 15 Jun 22 Aug 17 – Sep 14 55–70
Okra Apr 13 Jun 15 Jun 22 Aug 17 – Oct 12 50–65
Onion May 4 May 25 Jun 8 Sep 7 – Oct 26 90–120
Pac Choi May 4 May 25 Jun 8 Jul 20 – Aug 17 40–55
Parsnip May 25 Sep 7 – Oct 19 100–130
Patty Pan Squash May 4 Jun 15 Jun 22 Aug 10 – Sep 7 45–60
Peas May 4 May 25 Jun 8 Aug 3 – Sep 28 55–70
Peppers Mar 30 Jun 15 Jun 22 Aug 24 – Nov 2 60–90
Pole Beans Apr 13 Jun 15 Jun 22 Aug 17 – Oct 12 55–70
Potatoes Apr 13 Jun 15 Jun 22 Aug 31 – Nov 9 70–120
Pumpkin May 4 Jun 15 Jun 22 Sep 21 – Nov 9 85–120
Purslane May 4 May 25 Jun 8 Jul 20 – Aug 24 40–60
Radicchio May 4 May 25 Jun 8 Aug 10 – Sep 14 60–80
Radish May 25 Jun 22 – Jul 13 22–35
Rhubarb Jun 29 365–730
Romanesco May 4 May 25 Jun 8 Aug 24 – Oct 5 75–100
Rutabaga May 25 Aug 17 – Sep 21 80–100
Salsify May 25 Sep 7 – Oct 19 100–130
Savoy Cabbage May 4 May 25 Jun 8 Aug 17 – Oct 12 70–110
Scallions May 4 May 25 Jun 8 Aug 3 – Aug 31 50–70
Scarlet Runner Beans Apr 13 Jun 15 Jun 22 Aug 24 – Sep 28 60–80
Shallot May 4 May 25 Jun 8 Sep 7 – Oct 26 90–120
Shiso Apr 20 Jun 15 Jun 22 Aug 17 – Oct 12 50–70
Snap Peas Apr 13 Jun 15 Jun 22 Aug 17 – Oct 12 55–70
Snow Peas May 4 May 25 Jun 8 Aug 3 – Sep 28 50–65
Soybeans Jun 15 Sep 7 – Nov 2 80–120
Spaghetti Squash May 4 Jun 15 Jun 22 Sep 21 – Oct 19 85–100
Spinach May 4 May 25 Jun 8 Jul 13 – Sep 14 35–50
Squash (Summer) May 4 Jun 15 Jun 22 Aug 10 – Oct 12 45–65
Squash (Winter) May 4 Jun 15 Jun 22 Sep 14 – Nov 9 80–120
Sunchoke Jun 22 Oct 12 – Dec 7 110–150
Sunflower Apr 13 Jun 15 Jun 22 Aug 31 – Oct 19 70–100
Sweet Corn Jun 15 Aug 17 – Sep 28 60–90
Sweet Potatoes Apr 13 Jun 15 Jun 22 Sep 21 – Nov 9 90–120
Tatsoi May 4 May 25 Jun 8 Jul 13 – Aug 17 35–50
Tomatillo Apr 13 Jun 15 Jun 22 Aug 24 – Nov 2 60–85
Tomatoes Apr 13 Jun 15 Jun 22 Aug 24 – Nov 2 60–85
Turnip May 25 Jul 6 – Aug 10 40–60
Watercress May 4 May 25 Jun 8 Jul 20 – Aug 24 40–60
Watermelon May 4 Jun 15 Jun 22 Aug 31 – Oct 19 70–100
Wax Beans Jun 15 Aug 10 – Oct 5 50–65
Winter Melon Apr 13 Jun 15 Jun 22 Sep 21 – Nov 9 90–120
Yard Long Beans Apr 13 Jun 15 Jun 22 Aug 17 – Sep 28 55–80
Zucchini May 4 Jun 15 Jun 22 Aug 10 – Oct 5 45–60

🍓 Fruits to Grow in Costilla County

27 fruits that grow well in Zone 5b with planting dates for Costilla County.

Show all 27 fruits with planting dates
Plant Start Indoors Direct Sow Transplant Harvest Days to Maturity
Alpine Strawberries Jun 29 Sep 28 – Dec 14 90–180
Aronia Jun 29 730–1095
Blackberries Jun 29 365–730
Blueberries Jun 29 730–1095
Boysenberries Jun 29 365–730
Cantaloupe Jun 29 Sep 7 – Oct 12 70–90
Che Fruit Jun 29 1095–1825
Cranberries Jun 29 730–1095
Currants Jun 29 730–1095
Elderberries Jun 29 730–1095
Goji Berries Jun 29 730–1095
Gooseberries Jun 29 730–1095
Grapes Jun 29 730–1095
Ground Cherry Jun 29 Sep 7 – Nov 2 65–80
Hardy Kiwi Jun 29 1095–1825
Haskaps Jun 29 730–1095
Honeydew Jun 29 Sep 21 – Nov 2 80–110
Jostaberry Jun 29 730–1095
Lingonberries Jun 29 730–1095
Medlar Jun 29 1095–1825
Mulberries Jun 29 730–1825
Pawpaw Jun 29 1095–2555
Persimmon Jun 29 1095–2555
Quince Jun 29 1095–1825
Raspberries Jun 29 365–730
Serviceberries Jun 29 730–1095
Strawberries Jun 29 Sep 28 – Dec 14 90–365

🌿 Herbs to Grow in Costilla County

37 herbs that grow well in Zone 5b with planting dates for Costilla County.

Show all 37 herbs with planting dates
Plant Start Indoors Direct Sow Transplant Harvest Days to Maturity
Angelica May 4 May 25 Jun 1 365–730
Anise May 4 May 25 Jun 1 Aug 31 – Nov 16 90–120
Basil Apr 20 Jun 15 Jun 22 Aug 17 – Oct 19 50–75
Bee Balm Jun 15 Sep 14 – Nov 30 90–120
Borage May 4 May 25 Jun 1 Jul 27 – Sep 14 50–60
Caraway May 4 May 25 Jun 1 365–450
Catnip Jun 15 Aug 17 – Oct 19 60–80
Chamomile May 4 May 25 Jun 1 Aug 3 – Oct 12 60–90
Chervil May 4 May 25 Jun 1 Jul 13 – Sep 14 40–60
Chives Jun 15 Aug 17 – Oct 26 60–90
Cilantro May 4 May 25 Jun 1 Jul 13 – Sep 14 40–60
Comfrey Jun 15 Aug 17 – Oct 26 60–90
Cumin May 4 May 25 Jun 1 Sep 14 – Nov 16 100–120
Dill May 4 May 25 Jun 1 Jul 13 – Sep 14 40–60
Echinacea Jun 15 Oct 19 – Nov 30 120–180
Epazote Apr 20 Jun 15 Jun 22 Aug 10 – Oct 5 45–60
Fennel (herb) May 4 May 25 Jun 1 Aug 3 – Oct 12 60–90
Feverfew Jun 15 Sep 14 – Nov 30 90–120
Garlic Chives Jun 15 Aug 17 – Oct 26 60–90
Horehound Jun 15 Aug 31 – Oct 26 75–90
Hyssop Jun 15 Aug 24 – Oct 26 70–90
Lavender Jun 15 Sep 14 – Nov 30 90–200
Lemon Balm Jun 15 Aug 17 – Oct 5 60–70
Lemon Thyme Jun 15 Aug 24 – Oct 26 70–90
Lovage Jun 15 Aug 24 – Oct 26 70–90
Mint Jun 15 Aug 17 – Oct 26 60–90
Oregano Jun 15 Aug 17 – Oct 26 60–90
Parsley May 4 May 25 Jun 1 Aug 3 – Oct 5 60–80
Rue Jun 15 Aug 24 – Oct 26 70–90
Sage Jun 15 Aug 31 – Oct 26 75–90
Savory Jun 15 Aug 10 – Oct 5 50–70
Sorrel May 4 May 25 Jun 1 Jul 13 – Sep 14 40–60
Tarragon Jun 15 Aug 17 – Oct 26 60–90
Thai Basil Apr 20 Jun 15 Jun 22 Aug 17 – Oct 19 50–75
Thyme Jun 15 Aug 24 – Oct 26 70–90
Valerian Jun 15 Oct 19 – Nov 30 120–180
Yarrow Jun 15 Sep 14 – Nov 30 90–120
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Monthly Planting Guide for Costilla County

Gardening Guides & Resources

Helpful guides from The Ultimate Homestead to improve your garden in Costilla County.

Frequently Asked Questions

What planting zone is Costilla County, CO?

Costilla County is in USDA Hardiness Zone 5b. 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 Costilla County, CO?

Based on 31 years of NOAA weather station data, the median last spring frost in Costilla County falls around June 8. In 8 out of 10 years, last frost lands between May 24 and June 19 — a 26-day window of variability. Use June 19 as your conservative safe-to-plant date for frost-sensitive crops.

When is the first fall frost in Costilla County, CO?

The median first fall frost in Costilla County arrives around September 16. In cold years it can arrive as early as September 6; in mild years as late as September 29. Harvest or protect frost-sensitive crops — tomatoes, peppers, basil, squash — before this date.

How long is the growing season in Costilla County?

Costilla County has a frost-free growing season of approximately 100 days. Focus on short-season varieties and start warm-season crops indoors 6–8 weeks before last frost.

What is the soil like in Costilla County for gardening?

Costilla County has predominantly Loam soil with a pH range of 6.2–8.3 and Excessively Drained drainage. Most vegetables and herbs grow well with standard composting and seasonal soil amendment.

What is grown commercially in Costilla County?

Costilla County has commercial agriculture that includes Cattle, Hay, Wheat. These crops reflect the local climate and soil conditions — what succeeds commercially often translates well to home gardens in the same area.

Is Costilla County a good location for home gardening?

Costilla County scores 49/100 (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 Costilla County Garden Planner — Free

A 24-page printable planner built for Costilla County (Zone 5b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

Instant PDF download. No spam, unsubscribe any time.

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Composting Guide for Homesteaders

Composting Guide for Homesteaders

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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
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Data sources: USDA Plant Hardiness Zone Map (2023), NOAA GHCN-D daily station data (1994–2024) from 3 weather stations in or near Costilla County (31 years of records). Frost dates represent 50% probability averages; local conditions vary by elevation and microclimate. Last updated: May 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.