Dubuque County, IA — Planting Guide
Dubuque County is in USDA Zone 4b. The average last spring frost is April 29 and the first fall frost is October 9, giving you a growing season of approximately 163 days.
At an elevation of 1,243 ft, Dubuque County receives approximately 36.6 in of rainfall annually. The predominant soil type is Silt Loam.
Based on 31 years of NOAA climate station data, the last frost date here varies by 32 days year to year — ranging from April 13 in warm years to May 15 in cold years. The growing season is trending shorter by about 2.78 days per decade. Dubuque County scores 57/100 (Moderate) on the Microclimate Index.
🌡️ Zone
4b (-25°F to -20°F min)
❄️ Last Frost
April 29
🍂 First Frost
October 9
📅 Growing Season
163 days
⛰️ Elevation
1,243 ft
🌧️ Annual Rainfall
36.6 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 | 1.4 in | 8 days | — | None |
| Feb | 1.6 in | 6 days | — | None |
| Mar | 2.4 in | 8 days | — | None |
| Apr | 3.4 in | 10 days | 0.9 in | Moderate |
| May | 4.1 in | 12 days | 0.2 in | Low |
| Jun | 4.8 in | 9 days | — | Low |
| Jul | 4.3 in | 8 days | — | Low |
| Aug | 3.5 in | 9 days | 0.8 in | Moderate |
| Sep | 3.2 in | 7 days | 1.1 in | Moderate |
| Oct | 3.3 in | 7 days | 1 in | Moderate |
| Nov | 2.6 in | 8 days | — | None |
| Dec | 1.9 in | 7 days | — | None |
Annual total: 36.5 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.
Dubuque County Soil Profile
Soil Type
Silt Loam
Soil pH
5.8-7.3
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 15 | Oct 19 | 157 days |
| Cautious | May 6 | Oct 12 | 159 days |
| Average year | Apr 29 | Oct 9 | 163 days |
| Optimistic | Apr 24 | Oct 3 | 162 days |
| Aggressive (risky) | Apr 13 | Sep 21 | 161 days |
Not very — frost dates can vary by ±32 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 2.8 days per decade). Use the "Conservative" dates and choose fast-maturing varieties.
Gardening Difficulty Score
Dubuque County presents some gardening challenges. Choose adapted varieties and plan around frost dates.
Local Gardening Help in Dubuque 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 Dubuque County's climate and soil.
County Extension Office
Dubuque County Iowa State University Extension Extension Office
Phone: 515-294-6675
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 Dubuque County
Finding local nurseries & garden centers in Dubuque County
Why Buy Local
Local nurseries carry plants that are proven to grow in your area. Staff can give you advice specific to Dubuque 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 Dubuque County IA" or "garden center Dubuque 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 Dubuque County IA" or check your extension office and local parks department. Facebook groups like "Dubuque County Gardeners" or "Iowa 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
15.1 hours
Summer solstice daylight
Shortest Day
8.9 hours
Winter solstice daylight
Peak Sun Hours
9.3 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: 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 | 9.2 hr | 3.5 hr | Short day |
| February | 10.3 hr | 4.7 hr | Short day |
| March | 11.7 hr | 5.5 hr | Short day |
| April | 13.2 hr | 6.5 hr | Neutral |
| May | 14.4 hr | 8.1 hr | Long day |
| June | 15.1 hr | 9.1 hr | Long day |
| July | 14.8 hr | 9.3 hr | Long day |
| August | 13.7 hr | 8.8 hr | Neutral |
| September | 12.3 hr | 6.9 hr | Neutral |
| October | 10.8 hr | 5.9 hr | Short day |
| November | 9.5 hr | 3.8 hr | Short day |
| December | 8.9 hr | 3.4 hr | Short day |
Peak sun hours factor in typical cloud cover — use these for solar panel and shade-planning calculations.
Soil Temperature & Composting Calendar
Monthly soil temps tell you when to plant warm-season crops, and when your compost pile is actively working.
Plant Warm Crops When
Soil reaches 60°F+
Soil warm enough from Jun through Sep.
Best Month to Compost
Jul
Microbial activity peaks when soil is warm.
Active Composting
6 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 | 12°F | 24°F | ❄️ Dormant | ~36 weeks |
| Feb | 15°F | 21°F | ❄️ Dormant | ~36 weeks |
| Mar | 25°F | 27°F | ❄️ Dormant | ~36 weeks |
| Apr | 39°F | 40°F | ❄️ Dormant | ~36 weeks |
| May | 53°F | 51°F | ♻️ Active | ~14 weeks |
| Jun | 65°F | 59°F | ♻️ Active | ~14 weeks |
| Jul | 72°F | 65°F | 🔥 Peak | ~8 weeks |
| Aug | 71°F | 69°F | 🔥 Peak | ~8 weeks |
| Sep | 64°F | 63°F | ♻️ Active | ~14 weeks |
| Oct | 54°F | 54°F | ♻️ Active | ~14 weeks |
| Nov | 36°F | 44°F | ❄️ Dormant | ~36 weeks |
| Dec | 20°F | 30°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 Dubuque 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
Moderate — watch for mildew and blight during wet periods.
Seasonal Risk
View 5 common pests in your area
| Pest | Risk Level | Peak Months |
|---|---|---|
| Aphids | Moderate | May, Jun, Jul, Aug |
| Cabbage worms | Low | Jun, Jul, Aug |
| Colorado potato beetle | Low | Jun, Jul |
| Flea beetles | Low | May, Jun, Jul |
| Slugs | Low | May, Jun, Jul, Aug, Sep |
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 Dubuque County
Cover crops protect bare soil, fix nitrogen, suppress weeds, and improve soil structure — with county-specific planting dates.
Spring Cover Crops (2 options) — Build soil before the main growing season
| Crop | Plant By | Terminate | N-Fixing | Soil Benefit |
|---|---|---|---|---|
| Buckwheat | May 2 | Aug 7 | — | Rapid growth, attracts pollinators, suppresses weeds |
| White clover | Mar 29 | Aug 14 | ✓ 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 15 | Sep 18 | — | Deep roots break compaction, attract pollinators and beneficial insects |
Fall Cover Crops (5 options) — Plant after harvest to protect soil over winter
| Crop | Plant By | Terminate | N-Fixing | Soil Benefit |
|---|---|---|---|---|
| Daikon radish | Aug 12 | Apr 15 | — | Deep taproot breaks compaction, excellent for clay soils |
| Hairy vetch | Jul 14 | Apr 15 | ✓ Yes | Excellent nitrogen fixer, good for depleted soils |
| Oats | Aug 28 | Apr 8 | — | Quick biomass, winterkills in cold zones — no spring tillage needed |
| Winter rye | Jun 30 | Apr 8 | — | Suppresses weeds, prevents erosion, breaks up compacted soil |
| Winter wheat | Jul 16 | Apr 8 | — | 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: 11 mph Summer: 10 mph
Fall: 10 mph Winter: 11 mph
Prevailing wind: SW. Moderate wind — consider a temporary windbreak for young seedlings.
Windbreak Benefit
4.7/10
Moderately beneficial — a simple fence or trellis can protect delicate crops from wind stress.
Frost Pocket Risk
Low
Relatively flat terrain (114 ft range). Frost pocket risk is minimal — garden placement is flexible.
Rainwater Harvesting Potential
How much water you can collect, when to collect it, and what size system you need for your garden.
Annual Collection
18,191 gal
Per 1,000 sq ft of roof area (at 80% collection efficiency)
Recommended Setup
6 rain barrels (55 gal each)
For a typical 500 sq ft garden. Serious collectors: consider a 1,750 gal tank.
Legal Status
Unrestricted
Rainwater harvesting is fully legal in your state with no restrictions.
Best Collection Months
May, Jun, Jul, Aug
Highest rainfall months — your barrels will fill up quickly during these months.
Months to Draw From Storage
Jan, Feb, 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 36.5 inches of rain per year
- A 1,000 sq ft roof can collect roughly 18,191 gallons annually
- Rainwater harvesting is fully legal in your state
- Stock up on stored water before your dry season (Jan, Feb, Dec)
- Use a first-flush diverter to keep roof debris out of your collection
Soil & Growing Conditions in Dubuque County
Soil Type
Silt Loam
Soil pH 5.8–7.3 · Excessively Drained drainage
Native soil is well-suited to most vegetables and herbs with regular compost additions.
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
163-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 Dubuque County
96 vegetables that grow well in Zone 4b with planting dates for Dubuque County.
Show all 96 vegetables with planting dates
| Plant | Start Indoors | Direct Sow | Transplant | Harvest | Days to Maturity |
|---|---|---|---|---|---|
| Acorn Squash | Mar 18 | May 13 | May 20 | Aug 12 – Sep 16 | 80–100 |
| Amaranth | Feb 25 | May 13 | May 20 | Aug 19 – Oct 7 | 90–120 |
| Arugula | Mar 18 | Apr 22 | Apr 29 | Jun 3 – Aug 5 | 30–50 |
| Asparagus | — | — | May 13 | — | 730–1095 |
| Beets | — | Apr 22 | — | Jun 17 – Jul 15 | 50–70 |
| Belgian Endive | Mar 18 | Apr 22 | Apr 29 | Aug 19 – Sep 23 | 110–150 |
| Black Beans | — | May 13 | — | Aug 12 – Sep 30 | 90–120 |
| Bok Choy | Mar 18 | Apr 22 | Apr 29 | Jun 10 – Jul 15 | 40–60 |
| Broccoli | Mar 18 | Apr 22 | Apr 29 | Jul 1 – Aug 12 | 60–90 |
| Broccoli Rabe | Mar 18 | Apr 22 | Apr 29 | Jun 10 – Jul 15 | 40–60 |
| Brussels Sprouts | Mar 18 | Apr 22 | Apr 29 | Jul 29 – Sep 23 | 90–130 |
| Butternut Squash | Mar 18 | May 13 | May 20 | Aug 19 – Sep 23 | 85–110 |
| Cabbage | Mar 18 | Apr 22 | Apr 29 | Jul 1 – Aug 26 | 60–100 |
| Carrots | — | Apr 22 | — | Jun 24 – Jul 29 | 60–80 |
| Cauliflower | Mar 18 | Apr 22 | Apr 29 | Jun 24 – Aug 26 | 55–100 |
| Celeriac | Mar 18 | Apr 22 | Apr 29 | Aug 12 – Sep 16 | 100–120 |
| Celery | Mar 18 | Apr 22 | Apr 29 | Jul 22 – Sep 16 | 80–120 |
| Celtuce | Mar 18 | Apr 22 | Apr 29 | Jul 1 – Aug 12 | 60–90 |
| Chard | Mar 18 | Apr 22 | Apr 29 | Jun 24 – Aug 12 | 50–60 |
| Chickpeas | Mar 18 | Apr 22 | Apr 29 | Jul 22 – Sep 2 | 80–110 |
| Chicory | Mar 18 | Apr 22 | Apr 29 | Jul 1 – Aug 12 | 60–85 |
| Chinese Cabbage | Mar 18 | Apr 22 | Apr 29 | Jun 24 – Jul 22 | 50–70 |
| Christmas Lima Beans | Feb 25 | May 13 | May 20 | Aug 12 – Sep 16 | 80–100 |
| Collard Greens | Mar 18 | Apr 22 | Apr 29 | Jun 24 – Aug 26 | 55–75 |
| Corn | — | May 13 | — | Jul 15 – Sep 9 | 60–100 |
| Cress | Mar 18 | Apr 22 | Apr 29 | May 13 – Jun 3 | 14–21 |
| Crookneck Squash | Mar 18 | May 13 | May 20 | Jul 8 – Aug 5 | 45–60 |
| Crosne | — | Apr 22 | — | Sep 23 – Sep 16 | 150–200 |
| Cucumber | Mar 18 | May 13 | May 20 | Jul 15 – Sep 9 | 50–70 |
| Daikon | — | Apr 22 | — | Jun 17 – Jul 15 | 50–70 |
| Delicata Squash | Mar 18 | May 13 | May 20 | Aug 12 – Sep 16 | 80–100 |
| Edamame | — | May 13 | — | Jul 29 – Sep 9 | 75–100 |
| Endive | Mar 18 | Apr 22 | Apr 29 | Jun 17 – Jul 22 | 45–65 |
| Escarole | Mar 18 | Apr 22 | Apr 29 | Jun 24 – Jul 22 | 50–70 |
| Fava Beans | Mar 18 | Apr 22 | Apr 29 | Jul 15 – Aug 26 | 75–100 |
| Fennel | Feb 25 | May 13 | May 20 | Jul 22 – Sep 2 | 60–90 |
| Garlic | — | — | — | — | 90–240 |
| Green Beans | — | May 13 | — | Jul 8 – Sep 2 | 50–65 |
| Horseradish | — | — | May 13 | Sep 16 – Oct 7 | 120–180 |
| Hubbard Squash | Mar 18 | May 13 | May 20 | Sep 2 – Oct 7 | 100–120 |
| Kabocha | Mar 18 | May 13 | May 20 | Aug 19 – Sep 16 | 85–100 |
| Kai Lan | Mar 18 | Apr 22 | Apr 29 | Jun 17 – Jul 15 | 45–60 |
| Kale | Mar 18 | Apr 22 | Apr 29 | Jun 24 – Aug 19 | 50–70 |
| Kidney Beans | — | May 13 | — | Aug 12 – Sep 16 | 85–110 |
| Kohlrabi | Mar 18 | Apr 22 | Apr 29 | Jun 17 – Jul 22 | 45–65 |
| Komatsuna | Mar 18 | Apr 22 | Apr 29 | Jun 3 – Jul 8 | 35–50 |
| Leeks | Mar 18 | Apr 22 | Apr 29 | Jul 29 – Sep 23 | 90–150 |
| Lentils | Mar 18 | Apr 22 | Apr 29 | Jul 22 – Sep 2 | 80–110 |
| Lettuce | Mar 18 | Apr 22 | Apr 29 | Jun 3 – Aug 12 | 30–60 |
| Lima Beans | — | May 13 | — | Jul 15 – Aug 26 | 60–90 |
| Mache | Mar 18 | Apr 22 | Apr 29 | Jun 10 – Jul 15 | 40–60 |
| Melon | Mar 18 | May 13 | May 20 | Jul 29 – Sep 16 | 70–100 |
| Microgreens | Mar 18 | Apr 22 | Apr 29 | May 6 – Jun 3 | 7–21 |
| Mitsuba | Mar 18 | Apr 22 | Apr 22 | Jun 17 – Aug 12 | 50–70 |
| Mizuna | Mar 18 | Apr 22 | Apr 29 | Jun 3 – Jul 1 | 30–45 |
| Mustard Greens | Mar 18 | Apr 22 | Apr 29 | Jun 3 – Aug 5 | 30–50 |
| Napa Cabbage | Mar 18 | Apr 22 | Apr 29 | Jun 24 – Jul 29 | 55–75 |
| Onion | Mar 18 | Apr 22 | Apr 29 | Jul 29 – Sep 16 | 90–120 |
| Pac Choi | Mar 18 | Apr 22 | Apr 29 | Jun 10 – Jul 8 | 40–55 |
| Parsnip | — | Apr 22 | — | Aug 5 – Sep 16 | 100–130 |
| Patty Pan Squash | Mar 18 | May 13 | May 20 | Jul 8 – Aug 5 | 45–60 |
| Peas | Mar 18 | Apr 22 | Apr 29 | Jun 24 – Aug 19 | 55–70 |
| Peppers | Feb 11 | May 13 | May 20 | Jul 22 – Sep 30 | 60–90 |
| Pole Beans | Feb 25 | May 13 | May 20 | Jul 15 – Sep 9 | 55–70 |
| Potatoes | Feb 25 | May 13 | May 20 | Jul 29 – Oct 7 | 70–120 |
| Pumpkin | Mar 18 | May 13 | May 20 | Aug 19 – Oct 7 | 85–120 |
| Purslane | Mar 18 | Apr 22 | Apr 29 | Jun 10 – Jul 15 | 40–60 |
| Radicchio | Mar 18 | Apr 22 | Apr 29 | Jul 1 – Aug 5 | 60–80 |
| Radish | — | Apr 22 | — | May 20 – Jun 10 | 22–35 |
| Rhubarb | — | — | May 27 | — | 365–730 |
| Romanesco | Mar 18 | Apr 22 | Apr 29 | Jul 15 – Aug 26 | 75–100 |
| Rutabaga | — | Apr 22 | — | Jul 15 – Aug 19 | 80–100 |
| Salsify | — | Apr 22 | — | Aug 5 – Sep 16 | 100–130 |
| Savoy Cabbage | Mar 18 | Apr 22 | Apr 29 | Jul 8 – Sep 2 | 70–110 |
| Scallions | Mar 18 | Apr 22 | Apr 29 | Jun 24 – Jul 22 | 50–70 |
| Scarlet Runner Beans | Feb 25 | May 13 | May 20 | Jul 22 – Aug 26 | 60–80 |
| Shallot | Mar 18 | Apr 22 | Apr 29 | Jul 29 – Sep 16 | 90–120 |
| Shiso | Mar 4 | May 6 | May 20 | Jul 15 – Sep 9 | 50–70 |
| Snap Peas | Feb 25 | May 13 | May 20 | Jul 15 – Sep 9 | 55–70 |
| Snow Peas | Mar 18 | Apr 22 | Apr 29 | Jun 24 – Aug 19 | 50–65 |
| Soybeans | — | May 13 | — | Aug 5 – Sep 30 | 80–120 |
| Spaghetti Squash | Mar 18 | May 13 | May 20 | Aug 19 – Sep 16 | 85–100 |
| Spinach | Mar 18 | Apr 22 | Apr 29 | Jun 3 – Aug 5 | 35–50 |
| Squash (Summer) | Mar 18 | May 13 | May 20 | Jul 8 – Sep 9 | 45–65 |
| Squash (Winter) | Mar 18 | May 13 | May 20 | Aug 12 – Oct 7 | 80–120 |
| Sunchoke | — | — | May 13 | Sep 2 – Oct 7 | 110–150 |
| Sunflower | Feb 25 | May 13 | May 20 | Jul 29 – Sep 16 | 70–100 |
| Sweet Corn | — | May 13 | — | Jul 15 – Aug 26 | 60–90 |
| Tatsoi | Mar 18 | Apr 22 | Apr 29 | Jun 3 – Jul 8 | 35–50 |
| Tomatillo | Feb 25 | May 13 | May 20 | Jul 22 – Sep 30 | 60–85 |
| Tomatoes | Feb 25 | May 13 | May 20 | Jul 22 – Sep 30 | 60–85 |
| Turnip | — | Apr 22 | — | Jun 3 – Jul 8 | 40–60 |
| Watercress | Mar 18 | Apr 22 | Apr 29 | Jun 10 – Jul 15 | 40–60 |
| Watermelon | Mar 18 | May 13 | May 20 | Jul 29 – Sep 16 | 70–100 |
| Wax Beans | — | May 13 | — | Jul 8 – Sep 2 | 50–65 |
| Zucchini | Mar 18 | May 13 | May 20 | Jul 8 – Sep 2 | 45–60 |
🍓 Fruits to Grow in Dubuque County
22 fruits that grow well in Zone 4b with planting dates for Dubuque County.
Show all 22 fruits with planting dates
| Plant | Start Indoors | Direct Sow | Transplant | Harvest | Days to Maturity |
|---|---|---|---|---|---|
| Alpine Strawberries | — | — | May 27 | Aug 26 – Oct 21 | 90–180 |
| Aronia | — | — | May 27 | — | 730–1095 |
| Blueberries | — | — | May 27 | — | 730–1095 |
| Cantaloupe | — | — | May 27 | Aug 5 – Sep 9 | 70–90 |
| Cranberries | — | — | May 27 | — | 730–1095 |
| Currants | — | — | May 27 | — | 730–1095 |
| Elderberries | — | — | May 27 | — | 730–1095 |
| Goji Berries | — | — | May 27 | — | 730–1095 |
| Gooseberries | — | — | May 27 | — | 730–1095 |
| Grapes | — | — | May 27 | — | 730–1095 |
| Ground Cherry | — | — | May 27 | Aug 5 – Sep 30 | 65–80 |
| Hardy Kiwi | — | — | May 27 | — | 1095–1825 |
| Haskaps | — | — | May 27 | — | 730–1095 |
| Honeydew | — | — | May 27 | Aug 19 – Sep 30 | 80–110 |
| Jostaberry | — | — | May 27 | — | 730–1095 |
| Lingonberries | — | — | May 27 | — | 730–1095 |
| Medlar | — | — | May 27 | — | 1095–1825 |
| Mulberries | — | — | May 27 | — | 730–1825 |
| Persimmon | — | — | May 27 | — | 1095–2555 |
| Raspberries | — | — | May 27 | — | 365–730 |
| Serviceberries | — | — | May 27 | — | 730–1095 |
| Strawberries | — | — | May 27 | Aug 26 – Oct 21 | 90–365 |
🌿 Herbs to Grow in Dubuque County
32 herbs that grow well in Zone 4b with planting dates for Dubuque County.
Show all 32 herbs with planting dates
| Plant | Start Indoors | Direct Sow | Transplant | Harvest | Days to Maturity |
|---|---|---|---|---|---|
| Angelica | Mar 18 | Apr 22 | Apr 22 | — | 365–730 |
| Anise | Mar 18 | Apr 22 | Apr 22 | Jul 22 – Sep 16 | 90–120 |
| Basil | Mar 4 | May 6 | May 20 | Jul 15 – Sep 16 | 50–75 |
| Bee Balm | — | — | May 6 | Aug 5 – Sep 30 | 90–120 |
| Borage | Mar 18 | Apr 22 | Apr 22 | Jun 17 – Aug 5 | 50–60 |
| Caraway | Mar 18 | Apr 22 | Apr 22 | — | 365–450 |
| Catnip | — | — | May 6 | Jul 8 – Sep 9 | 60–80 |
| Chamomile | Mar 18 | Apr 22 | Apr 22 | Jun 24 – Sep 2 | 60–90 |
| Chervil | Mar 18 | Apr 22 | Apr 22 | Jun 3 – Aug 5 | 40–60 |
| Chives | — | — | May 6 | Jul 8 – Sep 16 | 60–90 |
| Cilantro | Mar 18 | Apr 22 | Apr 22 | Jun 3 – Aug 5 | 40–60 |
| Comfrey | — | — | May 6 | Jul 8 – Sep 16 | 60–90 |
| Dill | Mar 18 | Apr 22 | Apr 22 | Jun 3 – Aug 5 | 40–60 |
| Echinacea | — | — | May 6 | Sep 9 – Sep 30 | 120–180 |
| Fennel (herb) | Mar 18 | Apr 22 | Apr 22 | Jun 24 – Sep 2 | 60–90 |
| Garlic Chives | — | — | May 6 | Jul 8 – Sep 16 | 60–90 |
| Horehound | — | — | May 6 | Jul 22 – Sep 16 | 75–90 |
| Hyssop | — | — | May 6 | Jul 15 – Sep 16 | 70–90 |
| Lemon Balm | — | — | May 6 | Jul 8 – Aug 26 | 60–70 |
| Lovage | — | — | May 6 | Jul 15 – Sep 16 | 70–90 |
| Mint | — | — | May 6 | Jul 8 – Sep 16 | 60–90 |
| Oregano | — | — | May 6 | Jul 8 – Sep 16 | 60–90 |
| Parsley | Mar 18 | Apr 22 | Apr 22 | Jun 24 – Aug 26 | 60–80 |
| Rue | — | — | May 6 | Jul 15 – Sep 16 | 70–90 |
| Sage | — | — | May 6 | Jul 22 – Sep 16 | 75–90 |
| Savory | — | — | May 6 | Jul 1 – Aug 26 | 50–70 |
| Sorrel | Mar 18 | Apr 22 | Apr 22 | Jun 3 – Aug 5 | 40–60 |
| Tarragon | — | — | May 6 | Jul 8 – Sep 16 | 60–90 |
| Thai Basil | Mar 4 | May 6 | May 20 | Jul 15 – Sep 16 | 50–75 |
| Thyme | — | — | May 6 | Jul 15 – Sep 16 | 70–90 |
| Valerian | — | — | May 6 | Sep 9 – Sep 30 | 120–180 |
| Yarrow | — | — | May 6 | Aug 5 – Sep 30 | 90–120 |
Monthly Planting Guide for Dubuque County
Gardening Guides & Resources
Helpful guides from The Ultimate Homestead to improve your garden in Dubuque County.
Frequently Asked Questions
What planting zone is Dubuque County, IA?
Dubuque County is in USDA Hardiness Zone 4b. 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 Dubuque County, IA?
Based on 31 years of NOAA weather station data, the median last spring frost in Dubuque County falls around April 29. In 8 out of 10 years, last frost lands between April 13 and May 15 — a 32-day window of variability. Use May 15 as your conservative safe-to-plant date for frost-sensitive crops.
When is the first fall frost in Dubuque County, IA?
The median first fall frost in Dubuque County arrives around October 9. In cold years it can arrive as early as September 21; in mild years as late as October 19. Harvest or protect frost-sensitive crops — tomatoes, peppers, basil, squash — before this date.
How long is the growing season in Dubuque County?
Dubuque County has a frost-free growing season of approximately 163 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 shorter by about 2.78 days per decade.
What is the soil like in Dubuque County for gardening?
Dubuque County has predominantly Silt Loam soil with a pH range of 5.8–7.3 and Excessively Drained drainage. Most vegetables and herbs grow well with standard composting and seasonal soil amendment.
What is grown commercially in Dubuque County?
Dubuque County has commercial agriculture that includes Corn, Soybeans, Hay. These crops reflect the local climate and soil conditions — what succeeds commercially often translates well to home gardens in the same area.
Is Dubuque County a good location for home gardening?
Dubuque County scores 57/100 (Moderate) on our Microclimate Index, which combines frost reliability, drought pressure, soil challenge, elevation risk, and long-term climate trend. Conditions here are moderate — most common crops grow well with standard timing and care.
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