Delta County, CO — Planting Guide
Delta County is in USDA Zone 6a. The average last spring frost is May 1 and the first fall frost is October 8, giving you a growing season of approximately 160 days.
At an elevation of 4,470 ft, Delta County receives approximately 13.4 in of rainfall annually. Summer highs average 87°F with winter lows around 27°F. The predominant soil type is Loam.
Based on 31 years of NOAA climate station data, the last frost date here varies by 30 days year to year — ranging from April 17 in warm years to May 17 in cold years. The growing season is trending longer by about 4.66 days per decade. Delta County scores 33/100 (Challenging) on the Microclimate Index.
🌡️ Zone
6a (-10°F to -5°F min)
❄️ Last Frost
May 1
🍂 First Frost
October 8
📅 Growing Season
160 days
⛰️ Elevation
4,470 ft
🌧️ Annual Rainfall
13.4 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 | 1 in | 6 days | — | None |
| Feb | 0.7 in | 5 days | — | None |
| Mar | 1.2 in | 7 days | 3.1 in | Critical |
| Apr | 1.4 in | 8 days | 2.9 in | High |
| May | 1.4 in | 8 days | 2.9 in | High |
| Jun | 0.9 in | 5 days | 3.4 in | Critical |
| Jul | 1.3 in | 6 days | 3 in | High |
| Aug | 1.4 in | 6 days | 2.9 in | High |
| Sep | 1.1 in | 6 days | 3.2 in | Critical |
| Oct | 1.1 in | 6 days | 3.2 in | Critical |
| Nov | 1.1 in | 5 days | — | None |
| Dec | 0.8 in | 8 days | — | None |
Annual total: 13.4 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.
Delta County Soil Profile
Soil Type
Loam
Soil pH
6.7-7.8
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) | May 17 | Oct 25 | 161 days |
| Cautious | May 8 | Oct 13 | 158 days |
| Average year | May 1 | Oct 8 | 160 days |
| Optimistic | Apr 22 | Oct 4 | 165 days |
| Aggressive (risky) | Apr 17 | Sep 23 | 159 days |
Not very — frost dates can vary by ±30 days year-to-year. Use the "Conservative" row in the table below, and keep row covers handy for surprise late frosts.
Yes — growing seasons are getting longer here (about 4.7 days per decade). Spring is arriving earlier than it used to. Good news for gardeners.
Gardening Difficulty Score
Delta County has challenging growing conditions. Season extension and careful variety selection are essential.
Local Gardening Help in Delta 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 Delta County's climate and soil.
County Extension Office
Delta 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.
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 Delta County
Finding local nurseries & garden centers in Delta County
Why Buy Local
Local nurseries carry plants that are proven to grow in your area. Staff can give you advice specific to Delta 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 Delta County CO" or "garden center Delta 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 Delta County CO" or check your extension office and local parks department. Facebook groups like "Delta 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.
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
14.7 hours
Summer solstice daylight
Shortest Day
9.3 hours
Winter solstice daylight
Peak Sun Hours
10.4 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: Your long summer days (14+ hours) support long-day onion varieties like Walla Walla, Sweet Spanish, and Ailsa Craig.
View detailed monthly data
| Month | Daylight Hours | Peak Sun Hours | Day Length |
|---|---|---|---|
| January | 9.6 hr | 5.4 hr | Short day |
| February | 10.5 hr | 5.9 hr | Short day |
| March | 11.7 hr | 6.7 hr | Short day |
| April | 13 hr | 7.3 hr | Neutral |
| May | 14.1 hr | 8.7 hr | Long day |
| June | 14.7 hr | 10.4 hr | Long day |
| July | 14.5 hr | 10 hr | Long day |
| August | 13.5 hr | 9.4 hr | Neutral |
| September | 12.2 hr | 8.2 hr | Neutral |
| October | 11 hr | 7.4 hr | Short day |
| November | 9.8 hr | 5.5 hr | Short day |
| December | 9.3 hr | 5.1 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 Jun through Sep.
Best Month to Compost
Jul
Microbial activity peaks when soil is warm.
Active Composting
5 months
Solid season. Piles go dormant in winter.
View detailed monthly data
| Month | Soil 4" Deep | Soil 8" Deep | Compost Activity | Time to Finish |
|---|---|---|---|---|
| Jan | 20°F | 26°F | ❄️ Dormant | ~36 weeks |
| Feb | 18°F | 25°F | ❄️ Dormant | ~36 weeks |
| Mar | 27°F | 30°F | ❄️ Dormant | ~36 weeks |
| Apr | 39°F | 40°F | ❄️ Dormant | ~36 weeks |
| May | 50°F | 49°F | 🐢 Slow | ~24 weeks |
| Jun | 60°F | 57°F | ♻️ Active | ~14 weeks |
| Jul | 71°F | 64°F | 🔥 Peak | ~8 weeks |
| Aug | 70°F | 66°F | 🔥 Peak | ~8 weeks |
| Sep | 63°F | 64°F | ♻️ Active | ~14 weeks |
| Oct | 50°F | 54°F | ♻️ Active | ~14 weeks |
| Nov | 39°F | 42°F | ❄️ Dormant | ~36 weeks |
| Dec | 26°F | 35°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 Delta 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 | Low | 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 Delta 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 9 | Apr 17 | ✓ Yes | Fixes nitrogen, good for heavy clay soils |
| Crimson clover | Aug 16 | Apr 17 | ✓ Yes | Fixes nitrogen, attracts pollinators in spring |
| Daikon radish | Aug 25 | Apr 10 | — | Deep taproot breaks compaction, excellent for clay soils |
| Hairy vetch | Jul 22 | Apr 10 | ✓ Yes | Excellent nitrogen fixer, good for depleted soils |
| Oats | Aug 28 | Apr 10 | — | Quick biomass, winterkills in cold zones — no spring tillage needed |
| Winter rye | Jul 17 | Apr 17 | — | Suppresses weeds, prevents erosion, breaks up compacted soil |
| Winter wheat | Jul 12 | Apr 10 | — | 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 10 | Aug 6 | — | Rapid growth, attracts pollinators, suppresses weeds |
| Sorghum-sudan grass | May 5 | Aug 13 | — | Massive biomass, breaks compaction, suppresses nematodes |
| White clover | Apr 6 | Aug 6 | ✓ 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 1 | Sep 10 | — | 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: 16 mph Summer: 10 mph
Fall: 11 mph Winter: 14 mph
Prevailing wind: W. Windy area — plant a windbreak hedge on the W side of your garden.
Windbreak Benefit
7/10
Strongly recommended — a windbreak (fence, hedge, or row of tall crops like corn or sunflowers) will significantly improve garden yields.
Frost Pocket Risk
High
Hilly terrain with 1,417 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
6,678 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
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, 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 13.4 inches of rain per year
- A 1,000 sq ft roof can collect roughly 6,678 gallons annually
- Check CO state regulations — rainwater harvesting has quantity limits
- 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 Delta County
Soil Type
Loam
Soil pH 6.7–7.8 · Well 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
160-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
Test your soil pH, nitrogen, phosphorus, and potassium levels before planting.
Get instant, accurate soil pH readings to fine-tune your amendments.
Boost soil fertility and structure with rich, well-aged organic compost.
🥬 Vegetables to Grow in Delta County
108 vegetables that grow well in Zone 6a with planting dates for Delta County.
Show all 108 vegetables with planting dates
| Plant | Start Indoors | Direct Sow | Transplant | Harvest | Days to Maturity |
|---|---|---|---|---|---|
| Acorn Squash | Mar 27 | May 8 | May 15 | Aug 7 – Sep 11 | 80–100 |
| Amaranth | Mar 6 | May 8 | May 15 | Aug 14 – Oct 2 | 90–120 |
| Arugula | Mar 27 | Apr 17 | May 1 | Jun 5 – Aug 7 | 30–50 |
| Asparagus | — | — | May 15 | — | 730–1095 |
| Beets | — | Apr 17 | — | Jun 12 – Jul 10 | 50–70 |
| Belgian Endive | Mar 27 | Apr 17 | May 1 | Aug 21 – Oct 16 | 110–150 |
| Bitter Melon | Mar 6 | May 8 | May 15 | Jul 17 – Aug 28 | 60–90 |
| Black Beans | — | May 8 | — | Aug 7 – Sep 25 | 90–120 |
| Bok Choy | Mar 27 | Apr 17 | May 1 | Jun 12 – Jul 17 | 40–60 |
| Broccoli | Mar 27 | Apr 17 | May 1 | Jul 3 – Aug 14 | 60–90 |
| Broccoli Rabe | Mar 27 | Apr 17 | May 1 | Jun 12 – Jul 17 | 40–60 |
| Brussels Sprouts | Mar 27 | Apr 17 | May 1 | Jul 31 – Sep 25 | 90–130 |
| Butternut Squash | Mar 27 | May 8 | May 15 | Aug 14 – Sep 18 | 85–110 |
| Cabbage | Mar 27 | Apr 17 | May 1 | Jul 3 – Aug 28 | 60–100 |
| Calabash | Mar 6 | May 8 | May 15 | Aug 7 – Oct 2 | 80–120 |
| Carrots | — | Apr 17 | — | Jun 19 – Jul 24 | 60–80 |
| Cauliflower | Mar 27 | Apr 17 | May 1 | Jun 26 – Aug 28 | 55–100 |
| Celeriac | Mar 27 | Apr 17 | May 1 | Aug 14 – Sep 18 | 100–120 |
| Celery | Mar 27 | Apr 17 | May 1 | Jul 24 – Sep 18 | 80–120 |
| Celtuce | Mar 27 | Apr 17 | May 1 | Jul 3 – Aug 14 | 60–90 |
| Chard | Mar 27 | Apr 17 | May 1 | Jun 26 – Aug 14 | 50–60 |
| Chickpeas | Mar 27 | Apr 17 | May 1 | Jul 24 – Sep 4 | 80–110 |
| Chicory | Mar 27 | Apr 17 | May 1 | Jul 3 – Aug 14 | 60–85 |
| Chinese Cabbage | Mar 27 | Apr 17 | May 1 | Jun 26 – Jul 24 | 50–70 |
| Christmas Lima Beans | Mar 6 | May 8 | May 15 | Aug 7 – Sep 11 | 80–100 |
| Collard Greens | Mar 27 | Apr 17 | May 1 | Jun 26 – Aug 28 | 55–75 |
| Corn | — | May 8 | — | Jul 10 – Sep 4 | 60–100 |
| Cowpeas | — | May 8 | — | Jul 10 – Aug 21 | 60–90 |
| Cress | Mar 27 | Apr 17 | May 1 | May 15 – Jun 5 | 14–21 |
| Crookneck Squash | Mar 27 | May 8 | May 15 | Jul 3 – Jul 31 | 45–60 |
| Crosne | — | Apr 17 | — | Sep 18 – Oct 30 | 150–200 |
| Cucumber | Mar 27 | May 8 | May 15 | Jul 10 – Sep 4 | 50–70 |
| Daikon | — | Apr 17 | — | Jun 12 – Jul 10 | 50–70 |
| Delicata Squash | Mar 27 | May 8 | May 15 | Aug 7 – Sep 11 | 80–100 |
| Edamame | — | May 8 | — | Jul 24 – Sep 4 | 75–100 |
| Eggplant | Feb 20 | May 8 | May 15 | Jul 24 – Sep 25 | 65–85 |
| Endive | Mar 27 | Apr 17 | May 1 | Jun 19 – Jul 24 | 45–65 |
| Escarole | Mar 27 | Apr 17 | May 1 | Jun 26 – Jul 24 | 50–70 |
| Fava Beans | Mar 27 | Apr 17 | May 1 | Jul 17 – Aug 28 | 75–100 |
| Fennel | Mar 6 | May 8 | May 15 | Jul 17 – Aug 28 | 60–90 |
| Garlic | — | — | — | — | 90–240 |
| Green Beans | — | May 8 | — | Jul 3 – Aug 28 | 50–65 |
| Horseradish | — | — | May 15 | Sep 18 – Nov 27 | 120–180 |
| Hot Peppers | Feb 20 | May 8 | May 15 | Jul 24 – Oct 30 | 70–120 |
| Hubbard Squash | Mar 27 | May 8 | May 15 | Aug 28 – Oct 2 | 100–120 |
| Kabocha | Mar 27 | May 8 | May 15 | Aug 14 – Sep 11 | 85–100 |
| Kai Lan | Mar 27 | Apr 17 | May 1 | Jun 19 – Jul 17 | 45–60 |
| Kale | Mar 27 | Apr 17 | May 1 | Jun 26 – Aug 21 | 50–70 |
| Kidney Beans | — | May 8 | — | Aug 7 – Sep 11 | 85–110 |
| Kohlrabi | Mar 27 | Apr 17 | May 1 | Jun 19 – Jul 24 | 45–65 |
| Komatsuna | Mar 27 | Apr 17 | May 1 | Jun 5 – Jul 10 | 35–50 |
| Leeks | Mar 27 | Apr 17 | May 1 | Jul 31 – Oct 16 | 90–150 |
| Lentils | Mar 27 | Apr 17 | May 1 | Jul 24 – Sep 4 | 80–110 |
| Lettuce | Mar 27 | Apr 17 | May 1 | Jun 5 – Aug 14 | 30–60 |
| Lima Beans | — | May 8 | — | Jul 10 – Aug 21 | 60–90 |
| Loofah | Mar 6 | May 8 | May 15 | Aug 28 – Oct 30 | 100–150 |
| Luffa | Mar 6 | May 8 | May 15 | Aug 14 – Oct 30 | 90–150 |
| Mache | Mar 27 | Apr 17 | May 1 | Jun 12 – Jul 17 | 40–60 |
| Melon | Mar 27 | May 8 | May 15 | Jul 24 – Sep 11 | 70–100 |
| Microgreens | Mar 27 | Apr 17 | May 1 | May 8 – Jun 5 | 7–21 |
| Mitsuba | Mar 27 | Apr 17 | Apr 24 | Jun 19 – Aug 14 | 50–70 |
| Mizuna | Mar 27 | Apr 17 | May 1 | Jun 5 – Jul 3 | 30–45 |
| Mustard Greens | Mar 27 | Apr 17 | May 1 | Jun 5 – Aug 7 | 30–50 |
| Napa Cabbage | Mar 27 | Apr 17 | May 1 | Jun 26 – Jul 31 | 55–75 |
| New Zealand Spinach | Mar 6 | May 8 | May 15 | Jul 10 – Aug 7 | 55–70 |
| Okra | Mar 6 | May 8 | May 15 | Jul 10 – Sep 4 | 50–65 |
| Onion | Mar 27 | Apr 17 | May 1 | Jul 31 – Sep 18 | 90–120 |
| Pac Choi | Mar 27 | Apr 17 | May 1 | Jun 12 – Jul 10 | 40–55 |
| Parsnip | — | Apr 17 | — | Jul 31 – Sep 11 | 100–130 |
| Patty Pan Squash | Mar 27 | May 8 | May 15 | Jul 3 – Jul 31 | 45–60 |
| Peas | Mar 27 | Apr 17 | May 1 | Jun 26 – Aug 21 | 55–70 |
| Peppers | Feb 20 | May 8 | May 15 | Jul 17 – Sep 25 | 60–90 |
| Pole Beans | Mar 6 | May 8 | May 15 | Jul 10 – Sep 4 | 55–70 |
| Potatoes | Mar 6 | May 8 | May 15 | Jul 24 – Oct 2 | 70–120 |
| Pumpkin | Mar 27 | May 8 | May 15 | Aug 14 – Oct 2 | 85–120 |
| Purslane | Mar 27 | Apr 17 | May 1 | Jun 12 – Jul 17 | 40–60 |
| Radicchio | Mar 27 | Apr 17 | May 1 | Jul 3 – Aug 7 | 60–80 |
| Radish | — | Apr 17 | — | May 15 – Jun 5 | 22–35 |
| Rhubarb | — | — | May 22 | — | 365–730 |
| Romanesco | Mar 27 | Apr 17 | May 1 | Jul 17 – Aug 28 | 75–100 |
| Rutabaga | — | Apr 17 | — | Jul 10 – Aug 14 | 80–100 |
| Salsify | — | Apr 17 | — | Jul 31 – Sep 11 | 100–130 |
| Savoy Cabbage | Mar 27 | Apr 17 | May 1 | Jul 10 – Sep 4 | 70–110 |
| Scallions | Mar 27 | Apr 17 | May 1 | Jun 26 – Jul 24 | 50–70 |
| Scarlet Runner Beans | Mar 6 | May 8 | May 15 | Jul 17 – Aug 21 | 60–80 |
| Shallot | Mar 27 | Apr 17 | May 1 | Jul 31 – Sep 18 | 90–120 |
| Shiso | Mar 13 | May 8 | May 15 | Jul 10 – Sep 4 | 50–70 |
| Snap Peas | Mar 6 | May 8 | May 15 | Jul 10 – Sep 4 | 55–70 |
| Snow Peas | Mar 27 | Apr 17 | May 1 | Jun 26 – Aug 21 | 50–65 |
| Soybeans | — | May 8 | — | Jul 31 – Sep 25 | 80–120 |
| Spaghetti Squash | Mar 27 | May 8 | May 15 | Aug 14 – Sep 11 | 85–100 |
| Spinach | Mar 27 | Apr 17 | May 1 | Jun 5 – Aug 7 | 35–50 |
| Squash (Summer) | Mar 27 | May 8 | May 15 | Jul 3 – Sep 4 | 45–65 |
| Squash (Winter) | Mar 27 | May 8 | May 15 | Aug 7 – Oct 2 | 80–120 |
| Sunchoke | — | — | May 15 | Sep 4 – Oct 30 | 110–150 |
| Sunflower | Mar 6 | May 8 | May 15 | Jul 24 – Sep 11 | 70–100 |
| Sweet Corn | — | May 8 | — | Jul 10 – Aug 21 | 60–90 |
| Sweet Potatoes | Mar 6 | May 8 | May 15 | Aug 14 – Oct 2 | 90–120 |
| Tatsoi | Mar 27 | Apr 17 | May 1 | Jun 5 – Jul 10 | 35–50 |
| Tomatillo | Mar 6 | May 8 | May 15 | Jul 17 – Sep 25 | 60–85 |
| Tomatoes | Mar 6 | May 8 | May 15 | Jul 17 – Sep 25 | 60–85 |
| Turnip | — | Apr 17 | — | May 29 – Jul 3 | 40–60 |
| Watercress | Mar 27 | Apr 17 | May 1 | Jun 12 – Jul 17 | 40–60 |
| Watermelon | Mar 27 | May 8 | May 15 | Jul 24 – Sep 11 | 70–100 |
| Wax Beans | — | May 8 | — | Jul 3 – Aug 28 | 50–65 |
| Winter Melon | Mar 6 | May 8 | May 15 | Aug 14 – Oct 2 | 90–120 |
| Yard Long Beans | Mar 6 | May 8 | May 15 | Jul 10 – Aug 21 | 55–80 |
| Zucchini | Mar 27 | May 8 | May 15 | Jul 3 – Aug 28 | 45–60 |
🍓 Fruits to Grow in Delta County
27 fruits that grow well in Zone 6a with planting dates for Delta County.
Show all 27 fruits with planting dates
| Plant | Start Indoors | Direct Sow | Transplant | Harvest | Days to Maturity |
|---|---|---|---|---|---|
| Alpine Strawberries | — | — | May 22 | Aug 21 – Dec 4 | 90–180 |
| Aronia | — | — | May 22 | — | 730–1095 |
| Blackberries | — | — | May 22 | — | 365–730 |
| Blueberries | — | — | May 22 | — | 730–1095 |
| Boysenberries | — | — | May 22 | — | 365–730 |
| Cantaloupe | — | — | May 22 | Jul 31 – Sep 4 | 70–90 |
| Che Fruit | — | — | May 22 | — | 1095–1825 |
| Cranberries | — | — | May 22 | — | 730–1095 |
| Currants | — | — | May 22 | — | 730–1095 |
| Elderberries | — | — | May 22 | — | 730–1095 |
| Goji Berries | — | — | May 22 | — | 730–1095 |
| Gooseberries | — | — | May 22 | — | 730–1095 |
| Grapes | — | — | May 22 | — | 730–1095 |
| Ground Cherry | — | — | May 22 | Jul 31 – Sep 25 | 65–80 |
| Hardy Kiwi | — | — | May 22 | — | 1095–1825 |
| Haskaps | — | — | May 22 | — | 730–1095 |
| Honeydew | — | — | May 22 | Aug 14 – Sep 25 | 80–110 |
| Jostaberry | — | — | May 22 | — | 730–1095 |
| Lingonberries | — | — | May 22 | — | 730–1095 |
| Medlar | — | — | May 22 | — | 1095–1825 |
| Mulberries | — | — | May 22 | — | 730–1825 |
| Pawpaw | — | — | May 22 | — | 1095–2555 |
| Persimmon | — | — | May 22 | — | 1095–2555 |
| Quince | — | — | May 22 | — | 1095–1825 |
| Raspberries | — | — | May 22 | — | 365–730 |
| Serviceberries | — | — | May 22 | — | 730–1095 |
| Strawberries | — | — | May 22 | Aug 21 – Dec 4 | 90–365 |
🌿 Herbs to Grow in Delta County
38 herbs that grow well in Zone 6a with planting dates for Delta County.
Show all 38 herbs with planting dates
| Plant | Start Indoors | Direct Sow | Transplant | Harvest | Days to Maturity |
|---|---|---|---|---|---|
| Angelica | Mar 27 | Apr 17 | Apr 24 | — | 365–730 |
| Anise | Mar 27 | Apr 17 | Apr 24 | Jul 24 – Oct 9 | 90–120 |
| Basil | Mar 13 | May 8 | May 15 | Jul 10 – Sep 11 | 50–75 |
| Bee Balm | — | — | May 8 | Aug 7 – Oct 23 | 90–120 |
| Borage | Mar 27 | Apr 17 | Apr 24 | Jun 19 – Aug 7 | 50–60 |
| Caraway | Mar 27 | Apr 17 | Apr 24 | — | 365–450 |
| Catnip | — | — | May 8 | Jul 10 – Sep 11 | 60–80 |
| Chamomile | Mar 27 | Apr 17 | Apr 24 | Jun 26 – Sep 4 | 60–90 |
| Chervil | Mar 27 | Apr 17 | Apr 24 | Jun 5 – Aug 7 | 40–60 |
| Chives | — | — | May 8 | Jul 10 – Sep 18 | 60–90 |
| Cilantro | Mar 27 | Apr 17 | Apr 24 | Jun 5 – Aug 7 | 40–60 |
| Comfrey | — | — | May 8 | Jul 10 – Sep 18 | 60–90 |
| Cumin | Mar 27 | Apr 17 | Apr 24 | Aug 7 – Oct 9 | 100–120 |
| Dill | Mar 27 | Apr 17 | Apr 24 | Jun 5 – Aug 7 | 40–60 |
| Echinacea | — | — | May 8 | Sep 11 – Nov 20 | 120–180 |
| Epazote | Mar 13 | May 8 | May 15 | Jul 3 – Aug 28 | 45–60 |
| Fennel (herb) | Mar 27 | Apr 17 | Apr 24 | Jun 26 – Sep 4 | 60–90 |
| Feverfew | — | — | May 8 | Aug 7 – Oct 23 | 90–120 |
| Garlic Chives | — | — | May 8 | Jul 10 – Sep 18 | 60–90 |
| Horehound | — | — | May 8 | Jul 24 – Sep 18 | 75–90 |
| Hyssop | — | — | May 8 | Jul 17 – Sep 18 | 70–90 |
| Lavender | — | — | May 8 | Aug 7 – Nov 20 | 90–200 |
| Lemon Balm | — | — | May 8 | Jul 10 – Aug 28 | 60–70 |
| Lemon Thyme | — | — | May 8 | Jul 17 – Sep 18 | 70–90 |
| Lovage | — | — | May 8 | Jul 17 – Sep 18 | 70–90 |
| Marjoram | — | — | May 8 | Jul 10 – Sep 18 | 60–90 |
| Mint | — | — | May 8 | Jul 10 – Sep 18 | 60–90 |
| Oregano | — | — | May 8 | Jul 10 – Sep 18 | 60–90 |
| Parsley | Mar 27 | Apr 17 | Apr 24 | Jun 26 – Aug 28 | 60–80 |
| Rue | — | — | May 8 | Jul 17 – Sep 18 | 70–90 |
| Sage | — | — | May 8 | Jul 24 – Sep 18 | 75–90 |
| Savory | — | — | May 8 | Jul 3 – Aug 28 | 50–70 |
| Sorrel | Mar 27 | Apr 17 | Apr 24 | Jun 5 – Aug 7 | 40–60 |
| Tarragon | — | — | May 8 | Jul 10 – Sep 18 | 60–90 |
| Thai Basil | Mar 13 | May 8 | May 15 | Jul 10 – Sep 11 | 50–75 |
| Thyme | — | — | May 8 | Jul 17 – Sep 18 | 70–90 |
| Valerian | — | — | May 8 | Sep 11 – Nov 20 | 120–180 |
| Yarrow | — | — | May 8 | Aug 7 – Oct 23 | 90–120 |
Monthly Planting Guide for Delta County
Gardening Guides & Resources
Helpful guides from The Ultimate Homestead to improve your garden in Delta County.
Frequently Asked Questions
What planting zone is Delta County, CO?
Delta 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 Delta County, CO?
Based on 31 years of NOAA weather station data, the median last spring frost in Delta County falls around May 1. In 8 out of 10 years, last frost lands between April 17 and May 17 — a 30-day window of variability. Use May 17 as your conservative safe-to-plant date for frost-sensitive crops.
When is the first fall frost in Delta County, CO?
The median first fall frost in Delta County arrives around October 8. In cold years it can arrive as early as September 23; in mild years as late as October 25. Harvest or protect frost-sensitive crops — tomatoes, peppers, basil, squash — before this date.
How long is the growing season in Delta County?
Delta County has a frost-free growing season of approximately 160 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 4.66 days per decade.
What is the soil like in Delta County for gardening?
Delta County has predominantly Loam soil with a pH range of 6.7–7.8 and Well Drained drainage. Most vegetables and herbs grow well with standard composting and seasonal soil amendment.
What is grown commercially in Delta County?
Delta 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 Delta County a good location for home gardening?
Delta County scores 33/100 (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 Delta 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.
