Simpson, IL — Planting Guide for June
Free PDF, personalized for your town's frost dates & climate. Drop your email — we'll send the link.
This month in Simpson, IL
Your garden in Simpson, IL is working on a schedule, even when you're not. Here's where you should be this June.
-
Get peppers, astilbe, and begonias seeds going inside
Your window is short. These crops want several weeks of indoor growth before they go outside.
-
It's harvest week for basil, carrots, and cucumber
Taste as you pick. The first ripe produce is the best feedback loop you'll get all season.
Get ahead of July
- First harvests: basil, cucumber, and green beans
Simpson has a classic four-season growing climate (Zone 7a). The last spring frost typically lands around April 7 and the first fall frost arrives around October 21 — a 197-day frost-free season that's long enough for tomatoes, peppers, melons, and a full succession of cool-weather crops on either side. The trick is timing: start warm-season seedlings indoors 6–8 weeks before last frost, harden them off, and plant out the week after your local frost date is statistically safe.
Soils trend Silt Loam — the gold standard for vegetables. Add 2–3" of compost annually to maintain it and you'll outgrow most of your neighbors.
Drought pressure is moderate (11.8 weeks/year on average). Mulching and drip irrigation pay for themselves quickly.
🌡️ USDA Zone
7a (0°F to 5°F min)
❄️ Avg. Last Frost
April 7
🍂 Avg. First Frost
October 21
📅 Growing Season
197 days
🌧️ Climate
Unknown 0.0" annual
💨 Wind
Moderate 6.3 mph avg
🥶 Frost Tier
Regular 0% frost-free years
🏜️ Drought
11.8 wk/yr trend stable
📍 ZIP Codes
1 ZIP
Monthly Watering Calendar for Simpson
When you'll need to water your garden — based on average monthly rainfall vs. the ~1 inch/week most gardens need.
For new gardeners: Watering by the calendar wastes water. Watering by the soil moisture (or by a free rain gauge) cuts your water use 30%+ and produces healthier roots. Simpson's 0" annual baseline is the starting point.
View detailed monthly data
| Month | Avg Rainfall | Rainy Days | Extra Water Needed | Watering Effort |
|---|---|---|---|---|
| Jan | 1.6 in | 8 days | — | None |
| Feb | 1.9 in | 7 days | — | None |
| Mar | 2.9 in | 8 days | 1.4 in | Moderate |
| Apr | 3.6 in | 11 days | 0.7 in | Moderate |
| May | 4.2 in | 12 days | 0.1 in | Low |
| Jun | 4.4 in | 9 days | — | Low |
| Jul | 4.8 in | 9 days | — | Low |
| Aug | 4.6 in | 10 days | — | Low |
| Sep | 3.3 in | 9 days | 1 in | Moderate |
| Oct | 3.2 in | 8 days | 1.1 in | Moderate |
| Nov | 2.9 in | 8 days | — | None |
| Dec | 2.3 in | 7 days | — | None |
Annual total: 39.7 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.
Simpson Soil Profile
Soil Type
Silt Loam
Soil pH
5.9-7.2
Drainage
Well Drained
Frost Risk Probability
Based on 31 years of NOAA weather station data from 3 stations
Beginners: Plant frost-sensitive crops (tomatoes, peppers, squash) after the "Safe" date on the left. Harvest or cover them before the "Protect by" date on the right. Hardy crops (lettuce, peas, kale) can go in the yellow transition zones.
How to read this table: "Conservative" means you're safe from frost 9 out of 10 years — best for beginners and frost-sensitive crops. "Average year" is the typical date. "Aggressive" means only 1 in 10 years is that warm — experienced gardeners with frost protection can try these dates.
| Planting Strategy | Last Spring Frost | First Fall Frost | Frost-Free Days |
|---|---|---|---|
| Conservative (safest) | Apr 21 | Nov 4 | 197 days |
| Cautious | Apr 14 | Oct 27 | 196 days |
| Average year | Apr 7 | Oct 21 | 197 days |
| Optimistic | Apr 3 | Oct 16 | 196 days |
| Aggressive (risky) | Mar 26 | Oct 5 | 193 days |
Not very — frost dates can vary by ±25 days year-to-year. Use the "Conservative" row in the table below, and keep row covers handy for surprise late frosts.
Slightly — seasons are trending a bit shorter (0.4 days/decade). Stay conservative with planting dates.
Gardening Difficulty Score
Johnson County offers good growing conditions. A little planning around frost dates goes a long way.
Local Gardening Help in Johnson 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 Johnson County's climate and soil.
County Extension Office
Johnson County University of Illinois Extension Extension Office
Phone: 217-333-7672
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 Johnson County
Finding local nurseries & garden centers in Johnson County
Why Buy Local
Local nurseries carry plants that are proven to grow in your area. Staff can give you advice specific to Johnson 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 Johnson County IL" or "garden center Johnson 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 Johnson County IL" or check your extension office and local parks department. Facebook groups like "Johnson County Gardeners" or "Illinois Gardening" are also excellent for local advice and plant swaps.
What to Plant After Your Harvest
After your first crops finish, use the remaining frost-free days to grow a second round.
Show 6 more succession options
Sunlight & Day Length in Simpson
Monthly daylight hours and peak sun — critical for onion varieties, photoperiod-sensitive plants, and solar garden planning.
What this means for you: Lettuce and cilantro "bolt" (go to seed) when days lengthen. Knowing your day-length curve helps you time spring plantings to harvest before the bolting trigger hits. Simpson's daylight ranges shape the planting calendar.
Longest Day
14.6 hours
Summer solstice daylight
Shortest Day
9.4 hours
Winter solstice daylight
Peak Sun Hours
9.1 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 | 9.7 hr | 3.8 hr | Short day |
| February | 10.6 hr | 4.8 hr | Short day |
| March | 11.7 hr | 5.8 hr | Short day |
| April | 13 hr | 6.9 hr | Neutral |
| May | 14 hr | 8.2 hr | Long day |
| June | 14.6 hr | 8.7 hr | Long day |
| July | 14.3 hr | 9.1 hr | Long day |
| August | 13.4 hr | 8.7 hr | Neutral |
| September | 12.2 hr | 6.8 hr | Neutral |
| October | 11 hr | 6 hr | Short day |
| November | 9.9 hr | 3.8 hr | Short day |
| December | 9.4 hr | 3.6 hr | Short day |
Peak sun hours factor in typical cloud cover — use these for solar panel and shade-planning calculations.
Soil Temperature & Composting in Simpson
Monthly soil temps tell you when to plant warm-season crops, and when your compost pile is actively working.
The practical takeaway: Watching soil temperature (not air) is the single biggest upgrade most new gardeners can make. Simpson's typical curve helps you plan — but a $5 soil thermometer in the bed beats any average.
Plant Warm Crops When
Soil reaches 60°F+
Soil warm enough from May through Oct.
Best Month to Compost
Jun
Microbial activity peaks when soil is warm.
Active Composting
8 months
Nearly year-round composting.
View detailed monthly data
| Month | Soil 4" Deep | Soil 8" Deep | Compost Activity | Time to Finish |
|---|---|---|---|---|
| Jan | 31°F | 40°F | ❄️ Dormant | ~36 weeks |
| Feb | 33°F | 39°F | ❄️ Dormant | ~36 weeks |
| Mar | 41°F | 42°F | 🐢 Slow | ~24 weeks |
| Apr | 51°F | 53°F | ♻️ Active | ~14 weeks |
| May | 62°F | 62°F | ♻️ Active | ~14 weeks |
| Jun | 73°F | 69°F | 🔥 Peak | ~8 weeks |
| Jul | 83°F | 77°F | 🔥 Peak | ~8 weeks |
| Aug | 84°F | 80°F | 🔥 Peak | ~8 weeks |
| Sep | 75°F | 76°F | 🔥 Peak | ~8 weeks |
| Oct | 64°F | 67°F | ♻️ Active | ~14 weeks |
| Nov | 50°F | 56°F | ♻️ Active | ~14 weeks |
| Dec | 38°F | 45°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 Simpson
Computed from local climate patterns — warmer, humid conditions increase pest generations and fungal disease risk.
What this means for you: Pest and disease pressure is the X-factor most beginners under-plan for. Simpson's climate determines whether you can mostly "plant and see" or whether you need a pest-management routine from the first seedling.
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 6 common pests in your area
| Pest | Risk Level | Peak Months |
|---|---|---|
| Aphids | High | Apr, May, Jun, Jul, Aug, Sep |
| Japanese beetles | High | 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
- 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 Simpson
Cover crops protect bare soil, fix nitrogen, suppress weeds, and improve soil structure — with planting dates calibrated for your area.
What this means for you: You don't need a farm to use cover crops. A 4x8 raised bed accepts cover crops just as well as a half-acre. Simpson's climate determines the calendar; the principle is universal.
Spring Cover Crops (3 options) — Build soil before the main growing season
| Crop | Plant By | Terminate | N-Fixing | Soil Benefit |
|---|---|---|---|---|
| Buckwheat | Apr 17 | Aug 12 | — | Rapid growth, attracts pollinators, suppresses weeds |
| Sorghum-sudan grass | Apr 9 | Aug 19 | — | Massive biomass, breaks compaction, suppresses nematodes |
| White clover | Mar 9 | Aug 19 | ✓ Yes | Living mulch, fixes nitrogen, permanent ground cover |
Summer Cover Crops (1 options) — Fill gaps and suppress weeds between plantings
| Crop | Plant By | Terminate | N-Fixing | Soil Benefit |
|---|---|---|---|---|
| Sunflowers | Apr 19 | Sep 23 | — | Deep roots break compaction, attract pollinators and beneficial insects |
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 | Mar 24 | ✓ Yes | Fixes nitrogen, good for heavy clay soils |
| Crimson clover | Aug 26 | Mar 24 | ✓ Yes | Fixes nitrogen, attracts pollinators in spring |
| Daikon radish | Sep 8 | Mar 24 | — | Deep taproot breaks compaction, excellent for clay soils |
| Hairy vetch | Aug 11 | Mar 17 | ✓ Yes | Excellent nitrogen fixer, good for depleted soils |
| Oats | Sep 11 | Mar 17 | — | Quick biomass, winterkills in cold zones — no spring tillage needed |
| Winter rye | Jul 23 | Mar 17 | — | Suppresses weeds, prevents erosion, breaks up compacted soil |
| Winter wheat | Jul 28 | Mar 17 | — | Erosion control, weed suppression, good biomass |
Wind & Microclimate in Simpson
For new gardeners: A 10 mph wind doesn't feel like much, but it triples leaf transpiration vs. still air. Simpson's 6.3 mph average means most days are gentle on plants, but consider how a 20+ mph spring gust would affect a flat of seedlings hardened off too quickly.
Wind dries soil, stresses plants, and affects frost patterns. Understanding your exposure helps with garden placement.
Seasonal Wind Speed
Spring: 12 mph Summer: 10 mph
Fall: 11 mph Winter: 13 mph
Prevailing wind: SW. Moderate wind — consider a temporary windbreak for young seedlings.
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
Low
Relatively flat terrain (112 ft range). Frost pocket risk is minimal — garden placement is flexible.
Rainwater Harvesting in Simpson
How much water you can collect, when to collect it, and what size system you need for your garden.
What this means for you: Captured rainwater is better for plants than tap water (no chlorine), works during water restrictions, and reduces stormwater runoff. Simpson's 0" annual rainfall is a meaningful pool — most homes could capture 10,000+ gallons a year with a decent system.
Annual Collection
19,786 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 1,500 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 39.7 inches of rain per year
- A 1,000 sq ft roof can collect roughly 19,786 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
🥬 Vegetables to Grow in Simpson
112 vegetables matched to Zone 7a with planting dates calibrated for Simpson.
Show all 112 vegetables with dates
| Plant | Start Indoors | Direct Sow | Transplant | Fall Plant | Harvest | Days to Maturity |
|---|---|---|---|---|---|---|
| Acorn Squash | Mar 10 | Apr 14 | Apr 21 | — | Jul 14 – Aug 18 | 80–100 |
| Amaranth | Feb 17 | Apr 14 | Apr 21 | — | Jul 21 – Sep 8 | 90–120 |
| Artichoke | — | — | Apr 21 | — | Aug 25 – Nov 3 | 120–180 |
| Arugula | Mar 3 | Mar 24 | Apr 7 | Aug 12 | May 12 – Jul 14 | 30–50 |
| Asparagus | — | — | Apr 21 | — | — | 730–1095 |
| Beets | — | Mar 24 | — | Aug 12 | May 19 – Jun 16 | 50–70 |
| Belgian Endive | Mar 3 | Mar 24 | Apr 7 | Aug 12 | Jul 28 – Sep 22 | 110–150 |
| Bitter Melon | Feb 17 | Apr 14 | Apr 21 | — | Jun 23 – Aug 4 | 60–90 |
| Black Beans | — | Apr 14 | — | — | Jul 14 – Sep 1 | 90–120 |
| Bok Choy | Mar 3 | Mar 24 | Apr 7 | Aug 12 | May 19 – Jun 23 | 40–60 |
| Broccoli | Mar 3 | Mar 24 | Apr 7 | Aug 12 | Jun 9 – Jul 21 | 60–90 |
| Broccoli Rabe | Mar 3 | Mar 24 | Apr 7 | Aug 12 | May 19 – Jun 23 | 40–60 |
| Brussels Sprouts | Mar 3 | Mar 24 | Apr 7 | Aug 12 | Jul 7 – Sep 1 | 90–130 |
| Butternut Squash | Mar 10 | Apr 14 | Apr 21 | — | Jul 21 – Aug 25 | 85–110 |
| Cabbage | Mar 3 | Mar 24 | Apr 7 | Aug 12 | Jun 9 – Aug 4 | 60–100 |
| Calabash | Feb 17 | Apr 14 | Apr 21 | — | Jul 14 – Sep 8 | 80–120 |
| Cardoon | — | — | Apr 21 | — | Aug 25 – Oct 6 | 120–150 |
| Carrots | — | Mar 24 | — | Aug 12 | May 26 – Jun 30 | 60–80 |
| Cauliflower | Mar 3 | Mar 24 | Apr 7 | Aug 12 | Jun 2 – Aug 4 | 55–100 |
| Celeriac | Mar 3 | Mar 24 | Apr 7 | Aug 12 | Jul 21 – Aug 25 | 100–120 |
| Celery | Mar 3 | Mar 24 | Apr 7 | Aug 12 | Jun 30 – Aug 25 | 80–120 |
| Celtuce | Mar 3 | Mar 24 | Apr 7 | Aug 12 | Jun 9 – Jul 21 | 60–90 |
| Chard | Mar 3 | Mar 24 | Apr 7 | Aug 12 | Jun 2 – Jul 21 | 50–60 |
| Chayote | Feb 17 | Apr 14 | Apr 21 | — | Aug 25 – Nov 3 | 120–180 |
| Chickpeas | Mar 3 | Mar 24 | Apr 7 | Aug 12 | Jun 30 – Aug 11 | 80–110 |
| Chicory | Mar 3 | Mar 24 | Apr 7 | Aug 12 | Jun 9 – Jul 21 | 60–85 |
| Chinese Cabbage | Mar 3 | Mar 24 | Apr 7 | Aug 12 | Jun 2 – Jun 30 | 50–70 |
| Christmas Lima Beans | Feb 17 | Apr 14 | Apr 21 | — | Jul 14 – Aug 18 | 80–100 |
| Collard Greens | Mar 3 | Mar 24 | Apr 7 | Aug 12 | Jun 2 – Aug 4 | 55–75 |
| Corn | — | Apr 14 | — | — | Jun 16 – Aug 11 | 60–100 |
| Cowpeas | — | Apr 14 | — | — | Jun 16 – Jul 28 | 60–90 |
| Cress | Mar 3 | Mar 24 | Apr 7 | Aug 12 | Apr 21 – May 12 | 14–21 |
| Crookneck Squash | Mar 10 | Apr 14 | Apr 21 | — | Jun 9 – Jul 7 | 45–60 |
| Crosne | — | Mar 24 | — | Aug 12 | Aug 25 – Oct 27 | 150–200 |
| Cucumber | Mar 10 | Apr 14 | Apr 21 | — | Jun 16 – Aug 11 | 50–70 |
| Daikon | — | Mar 24 | — | Aug 12 | May 19 – Jun 16 | 50–70 |
| Delicata Squash | Mar 10 | Apr 14 | Apr 21 | — | Jul 14 – Aug 18 | 80–100 |
| Edamame | — | Apr 14 | — | — | Jun 30 – Aug 11 | 75–100 |
| Eggplant | Feb 3 | Apr 14 | Apr 21 | — | Jun 30 – Sep 1 | 65–85 |
| Endive | Mar 3 | Mar 24 | Apr 7 | Aug 12 | May 26 – Jun 30 | 45–65 |
| Escarole | Mar 3 | Mar 24 | Apr 7 | Aug 12 | Jun 2 – Jun 30 | 50–70 |
| Fava Beans | Mar 3 | Mar 24 | Apr 7 | Aug 12 | Jun 23 – Aug 4 | 75–100 |
| Fennel | Feb 17 | Apr 14 | Apr 21 | — | Jun 23 – Aug 4 | 60–90 |
| Garlic | — | — | — | Sep 9 | Dec 9 – Apr 21 | 90–240 |
| Green Beans | — | Apr 14 | — | — | Jun 9 – Aug 4 | 50–65 |
| Horseradish | — | — | Apr 21 | — | Aug 25 – Nov 3 | 120–180 |
| Hot Peppers | Feb 3 | Apr 14 | Apr 21 | — | Jun 30 – Oct 6 | 70–120 |
| Hubbard Squash | Mar 10 | Apr 14 | Apr 21 | — | Aug 4 – Sep 8 | 100–120 |
| Jicama | Feb 17 | Apr 14 | Apr 21 | — | Aug 25 – Nov 3 | 120–180 |
| Kabocha | Mar 10 | Apr 14 | Apr 21 | — | Jul 21 – Aug 18 | 85–100 |
| Kai Lan | Mar 3 | Mar 24 | Apr 7 | Aug 12 | May 26 – Jun 23 | 45–60 |
| Kale | Mar 3 | Mar 24 | Apr 7 | Aug 12 | Jun 2 – Jul 28 | 50–70 |
| Kidney Beans | — | Apr 14 | — | — | Jul 14 – Aug 18 | 85–110 |
| Kohlrabi | Mar 3 | Mar 24 | Apr 7 | Aug 12 | May 26 – Jun 30 | 45–65 |
| Komatsuna | Mar 3 | Mar 24 | Apr 7 | Aug 12 | May 12 – Jun 16 | 35–50 |
| Leeks | Mar 3 | Mar 24 | Apr 7 | Aug 12 | Jul 7 – Sep 22 | 90–150 |
| Lentils | Mar 3 | Mar 24 | Apr 7 | Aug 12 | Jun 30 – Aug 11 | 80–110 |
| Lettuce | Mar 3 | Mar 24 | Apr 7 | Aug 12 | May 12 – Jul 21 | 30–60 |
| Lima Beans | — | Apr 14 | — | — | Jun 16 – Jul 28 | 60–90 |
| Loofah | Feb 17 | Apr 14 | Apr 21 | — | Aug 4 – Oct 6 | 100–150 |
| Luffa | Feb 17 | Apr 14 | Apr 21 | — | Jul 21 – Oct 6 | 90–150 |
| Mache | Mar 3 | Mar 24 | Apr 7 | Aug 12 | May 19 – Jun 23 | 40–60 |
| Malabar Spinach | Feb 17 | Apr 14 | Apr 21 | — | Jun 16 – Jul 14 | 55–70 |
| Melon | Mar 10 | Apr 14 | Apr 21 | — | Jun 30 – Aug 18 | 70–100 |
| Microgreens | Mar 3 | Mar 24 | Apr 7 | Aug 12 | Apr 14 – May 12 | 7–21 |
| Mitsuba | Mar 3 | Mar 24 | Mar 31 | Aug 12 | May 26 – Jul 21 | 50–70 |
| Mizuna | Mar 3 | Mar 24 | Apr 7 | Aug 12 | May 12 – Jun 9 | 30–45 |
| Mustard Greens | Mar 3 | Mar 24 | Apr 7 | Aug 12 | May 12 – Jul 14 | 30–50 |
| Napa Cabbage | Mar 3 | Mar 24 | Apr 7 | Aug 12 | Jun 2 – Jul 7 | 55–75 |
| New Zealand Spinach | Feb 17 | Apr 14 | Apr 21 | — | Jun 16 – Jul 14 | 55–70 |
| Okra | Feb 17 | Apr 14 | Apr 21 | — | Jun 16 – Aug 11 | 50–65 |
| Onion | Mar 3 | Mar 24 | Apr 7 | Aug 12 | Jul 7 – Aug 25 | 90–120 |
| Pac Choi | Mar 3 | Mar 24 | Apr 7 | Aug 12 | May 19 – Jun 16 | 40–55 |
| Parsnip | — | Mar 24 | — | Aug 12 | Jul 7 – Aug 18 | 100–130 |
| Patty Pan Squash | Mar 10 | Apr 14 | Apr 21 | — | Jun 9 – Jul 7 | 45–60 |
| Peas | Mar 3 | Mar 24 | Apr 7 | Aug 12 | Jun 2 – Jul 28 | 55–70 |
| Peppers | Feb 3 | Apr 14 | Apr 21 | — | Jun 23 – Sep 1 | 60–90 |
| Pole Beans | Feb 17 | Apr 14 | Apr 21 | — | Jun 16 – Aug 11 | 55–70 |
| Potatoes | Feb 17 | Apr 14 | Apr 21 | — | Jun 30 – Sep 8 | 70–120 |
| Pumpkin | Mar 10 | Apr 14 | Apr 21 | — | Jul 21 – Sep 8 | 85–120 |
| Purslane | Mar 3 | Mar 24 | Apr 7 | Aug 12 | May 19 – Jun 23 | 40–60 |
| Radicchio | Mar 3 | Mar 24 | Apr 7 | Aug 12 | Jun 9 – Jul 14 | 60–80 |
| Radish | — | Mar 24 | — | Aug 12 | Apr 21 – May 12 | 22–35 |
| Rhubarb | — | — | Apr 28 | — | — | 365–730 |
| Romanesco | Mar 3 | Mar 24 | Apr 7 | Aug 12 | Jun 23 – Aug 4 | 75–100 |
| Rutabaga | — | Mar 24 | — | Aug 12 | Jun 16 – Jul 21 | 80–100 |
| Salsify | — | Mar 24 | — | Aug 12 | Jul 7 – Aug 18 | 100–130 |
| Savoy Cabbage | Mar 3 | Mar 24 | Apr 7 | Aug 12 | Jun 16 – Aug 11 | 70–110 |
| Scallions | Mar 3 | Mar 24 | Apr 7 | Aug 12 | Jun 2 – Jun 30 | 50–70 |
| Scarlet Runner Beans | Feb 17 | Apr 14 | Apr 21 | — | Jun 23 – Jul 28 | 60–80 |
| Shallot | Mar 3 | Mar 24 | Apr 7 | Aug 12 | Jul 7 – Aug 25 | 90–120 |
| Shiso | Feb 17 | Apr 14 | Apr 21 | — | Jun 16 – Aug 11 | 50–70 |
| Snap Peas | Feb 17 | Apr 14 | Apr 21 | — | Jun 16 – Aug 11 | 55–70 |
| Snow Peas | Mar 3 | Mar 24 | Apr 7 | Aug 12 | Jun 2 – Jul 28 | 50–65 |
| Soybeans | — | Apr 14 | — | — | Jul 7 – Sep 1 | 80–120 |
| Spaghetti Squash | Mar 10 | Apr 14 | Apr 21 | — | Jul 21 – Aug 18 | 85–100 |
| Spinach | Mar 3 | Mar 24 | Apr 7 | Aug 12 | May 12 – Jul 14 | 35–50 |
| Squash (Summer) | Mar 10 | Apr 14 | Apr 21 | — | Jun 9 – Aug 11 | 45–65 |
| Squash (Winter) | Mar 10 | Apr 14 | Apr 21 | — | Jul 14 – Sep 8 | 80–120 |
| Sunchoke | — | — | Apr 21 | — | Aug 11 – Oct 6 | 110–150 |
| Sweet Corn | — | Apr 14 | — | — | Jun 16 – Jul 28 | 60–90 |
| Sweet Potatoes | Feb 17 | Apr 14 | Apr 21 | — | Jul 21 – Sep 8 | 90–120 |
| Tatsoi | Mar 3 | Mar 24 | Apr 7 | Aug 12 | May 12 – Jun 16 | 35–50 |
| Tomatillo | Feb 17 | Apr 14 | Apr 21 | — | Jun 23 – Sep 1 | 60–85 |
| Tomatoes | Feb 17 | Apr 14 | Apr 21 | — | Jun 23 – Sep 1 | 60–85 |
| Turnip | — | Mar 24 | — | Aug 12 | May 5 – Jun 9 | 40–60 |
| Watercress | Mar 3 | Mar 24 | Apr 7 | Aug 12 | May 19 – Jun 23 | 40–60 |
| Watermelon | Mar 10 | Apr 14 | Apr 21 | — | Jun 30 – Aug 18 | 70–100 |
| Wax Beans | — | Apr 14 | — | — | Jun 9 – Aug 4 | 50–65 |
| Winter Melon | Feb 17 | Apr 14 | Apr 21 | — | Jul 21 – Sep 8 | 90–120 |
| Yard Long Beans | Feb 17 | Apr 14 | Apr 21 | — | Jun 16 – Jul 28 | 55–80 |
| Zucchini | Mar 10 | Apr 14 | Apr 21 | — | Jun 9 – Aug 4 | 45–60 |
🍓 Fruits to Grow in Simpson
31 fruits matched to Zone 7a with planting dates calibrated for Simpson.
Show all 31 fruits with dates
| Plant | Start Indoors | Direct Sow | Transplant | Fall Plant | Harvest | Days to Maturity |
|---|---|---|---|---|---|---|
| Alpine Strawberries | — | — | Apr 28 | — | Jul 28 – Nov 10 | 90–180 |
| Aronia | — | — | Apr 28 | — | — | 730–1095 |
| Blackberries | — | — | Apr 28 | — | — | 365–730 |
| Blueberries | — | — | Apr 28 | — | — | 730–1095 |
| Boysenberries | — | — | Apr 28 | — | — | 365–730 |
| Cantaloupe | — | — | Apr 28 | — | Jul 7 – Aug 11 | 70–90 |
| Che Fruit | — | — | Apr 28 | — | — | 1095–1825 |
| Cranberries | — | — | Apr 28 | — | — | 730–1095 |
| Currants | — | — | Apr 28 | — | — | 730–1095 |
| Elderberries | — | — | Apr 28 | — | — | 730–1095 |
| Figs | — | — | Apr 28 | — | — | 730–1825 |
| Goji Berries | — | — | Apr 28 | — | — | 730–1095 |
| Gooseberries | — | — | Apr 28 | — | — | 730–1095 |
| Grapes | — | — | Apr 28 | — | — | 730–1095 |
| Ground Cherry | — | — | Apr 28 | — | Jul 7 – Sep 1 | 65–80 |
| Hardy Kiwi | — | — | Apr 28 | — | — | 1095–1825 |
| Haskaps | — | — | Apr 28 | — | — | 730–1095 |
| Honeydew | — | — | Apr 28 | — | Jul 21 – Sep 1 | 80–110 |
| Jostaberry | — | — | Apr 28 | — | — | 730–1095 |
| Kiwi | — | — | Apr 28 | — | — | 1095–1825 |
| Lingonberries | — | — | Apr 28 | — | — | 730–1095 |
| Loquat | — | — | Apr 28 | — | — | 730–1825 |
| Medlar | — | — | Apr 28 | — | — | 1095–1825 |
| Mulberries | — | — | Apr 28 | — | — | 730–1825 |
| Pawpaw | — | — | Apr 28 | — | — | 1095–2555 |
| Persimmon | — | — | Apr 28 | — | — | 1095–2555 |
| Pomegranate | — | — | Apr 28 | — | — | 730–1095 |
| Quince | — | — | Apr 28 | — | — | 1095–1825 |
| Raspberries | — | — | Apr 28 | — | — | 365–730 |
| Serviceberries | — | — | Apr 28 | — | — | 730–1095 |
| Strawberries | — | — | Apr 28 | — | Jul 28 – Dec 8 | 90–365 |
🌿 Herbs to Grow in Simpson
36 herbs matched to Zone 7a with planting dates calibrated for Simpson.
Show all 36 herbs with dates
| Plant | Start Indoors | Direct Sow | Transplant | Fall Plant | Harvest | Days to Maturity |
|---|---|---|---|---|---|---|
| Angelica | Mar 3 | Mar 24 | Mar 31 | Aug 12 | — | 365–730 |
| Anise | Mar 3 | Mar 24 | Mar 31 | Aug 12 | Jun 30 – Sep 15 | 90–120 |
| Basil | Feb 17 | Apr 14 | Apr 21 | — | Jun 16 – Aug 18 | 50–75 |
| Bee Balm | — | — | Apr 14 | — | Jul 14 – Sep 29 | 90–120 |
| Borage | Mar 3 | Mar 24 | Mar 31 | Aug 12 | May 26 – Jul 14 | 50–60 |
| Caraway | Mar 3 | Mar 24 | Mar 31 | Aug 12 | — | 365–450 |
| Catnip | — | — | Apr 14 | — | Jun 16 – Aug 18 | 60–80 |
| Chamomile | Mar 3 | Mar 24 | Mar 31 | Aug 12 | Jun 2 – Aug 11 | 60–90 |
| Chervil | Mar 3 | Mar 24 | Mar 31 | Aug 12 | May 12 – Jul 14 | 40–60 |
| Chives | — | — | Apr 14 | — | Jun 16 – Aug 25 | 60–90 |
| Cilantro | Mar 3 | Mar 24 | Mar 31 | Aug 12 | May 12 – Jul 14 | 40–60 |
| Comfrey | — | — | Apr 14 | — | Jun 16 – Aug 25 | 60–90 |
| Cumin | Mar 3 | Mar 24 | Mar 31 | Aug 12 | Jul 14 – Sep 15 | 100–120 |
| Dill | Mar 3 | Mar 24 | Mar 31 | Aug 12 | May 12 – Jul 14 | 40–60 |
| Epazote | Feb 17 | Apr 14 | Apr 21 | — | Jun 9 – Aug 4 | 45–60 |
| Fennel (herb) | Mar 3 | Mar 24 | Mar 31 | Aug 12 | Jun 2 – Aug 11 | 60–90 |
| Feverfew | — | — | Apr 14 | — | Jul 14 – Sep 29 | 90–120 |
| Garlic Chives | — | — | Apr 14 | — | Jun 16 – Aug 25 | 60–90 |
| Horehound | — | — | Apr 14 | — | Jun 30 – Aug 25 | 75–90 |
| Hyssop | — | — | Apr 14 | — | Jun 23 – Aug 25 | 70–90 |
| Lemon Balm | — | — | Apr 14 | — | Jun 16 – Aug 4 | 60–70 |
| Lemon Thyme | — | — | Apr 14 | — | Jun 23 – Aug 25 | 70–90 |
| Lovage | — | — | Apr 14 | — | Jun 23 – Aug 25 | 70–90 |
| Marjoram | — | — | Apr 14 | — | Jun 16 – Aug 25 | 60–90 |
| Mint | — | — | Apr 14 | — | Jun 16 – Aug 25 | 60–90 |
| Oregano | — | — | Apr 14 | — | Jun 16 – Aug 25 | 60–90 |
| Parsley | Mar 3 | Mar 24 | Mar 31 | Aug 12 | Jun 2 – Aug 4 | 60–80 |
| Rosemary | — | — | Apr 14 | — | Jul 7 – Nov 24 | 80–180 |
| Rue | — | — | Apr 14 | — | Jun 23 – Aug 25 | 70–90 |
| Sage | — | — | Apr 14 | — | Jun 30 – Aug 25 | 75–90 |
| Savory | — | — | Apr 14 | — | Jun 9 – Aug 4 | 50–70 |
| Sorrel | Mar 3 | Mar 24 | Mar 31 | Aug 12 | May 12 – Jul 14 | 40–60 |
| Tarragon | — | — | Apr 14 | — | Jun 16 – Aug 25 | 60–90 |
| Thai Basil | Feb 17 | Apr 14 | Apr 21 | — | Jun 16 – Aug 18 | 50–75 |
| Thyme | — | — | Apr 14 | — | Jun 23 – Aug 25 | 70–90 |
| Valerian | — | — | Apr 14 | — | Aug 18 – Nov 24 | 120–180 |
🌸 Flowers to Grow in Simpson
53 flowers matched to Zone 7a with planting dates calibrated for Simpson.
Show all 53 flowers with dates
| Plant | Start Indoors | Direct Sow | Transplant | Fall Plant | Bloom | Days to Maturity |
|---|---|---|---|---|---|---|
| Ageratum | Feb 24 | Apr 7 | Apr 7 | — | Jun 2 – Sep 22 | 60–75 |
| Alliums | — | — | — | Sep 16 | Oct 14 – Nov 4 | 28–42 |
| Anemones | — | — | — | Aug 26 | Sep 9 – Oct 7 | 90–120 |
| Astilbe | Feb 3 | — | Apr 14 | — | Jun 23 – Aug 18 | 70–100 |
| Bachelor's Button | Feb 24 | Mar 3 | Apr 7 | Aug 26 | Jun 9 – Sep 8 | 60–90 |
| Begonias | Jan 27 | — | Apr 7 | — | Jun 16 – Oct 6 | 70–90 |
| Black-eyed Susan | Feb 3 | Apr 7 | Apr 14 | — | Jun 23 – Oct 27 | 60–80 |
| Bleeding Hearts | Feb 3 | — | Apr 14 | — | Jun 2 – Jul 7 | 60–90 |
| Calendula | Feb 24 | Mar 3 | Apr 7 | Aug 26 | May 26 – Sep 8 | 50–70 |
| California Poppy | — | Mar 10 | — | Aug 26 | May 19 – Jul 28 | 60–90 |
| Celosia | Mar 10 | Apr 7 | Apr 7 | — | Jun 9 – Oct 6 | 60–90 |
| Columbine | Feb 10 | Apr 14 | Apr 14 | — | Jun 2 – Jul 7 | 70–100 |
| Coreopsis | Feb 3 | Apr 7 | Apr 14 | — | Jun 16 – Oct 27 | 60–80 |
| Cosmos | Mar 10 | Apr 7 | Apr 7 | — | Jun 16 – Oct 6 | 60–90 |
| Crocus | — | — | — | Sep 16 | Aug 12 – Sep 2 | 10–20 |
| Daffodils | — | — | — | Sep 16 | Aug 19 – Sep 9 | 20–40 |
| Dahlias | Mar 10 | Apr 14 | Apr 14 | — | Jun 23 – Oct 27 | 70–120 |
| Daylily | Feb 3 | — | Apr 14 | — | Jun 23 – Oct 27 | 60–90 |
| Dianthus | Feb 10 | Mar 3 | Mar 17 | — | May 5 – Aug 4 | 60–80 |
| Echinacea (Purple Coneflower) | Feb 3 | Apr 14 | Apr 14 | — | Jun 30 – Oct 27 | 70–90 |
| Foxglove | Feb 10 | Apr 14 | Apr 14 | — | Jun 2 – Jul 7 | 80–120 |
| Gaillardia (Blanket Flower) | Feb 17 | Apr 14 | Apr 14 | — | Jun 23 – Nov 10 | 70–100 |
| Geraniums | Jan 27 | — | Apr 7 | — | Jun 16 – Oct 6 | 70–100 |
| Gladiolus | — | Apr 7 | Apr 7 | — | Jun 16 – Oct 20 | 70–100 |
| Hostas | Jan 27 | — | Apr 14 | — | Jun 23 – Oct 27 | 60–90 |
| Hyacinths | — | — | — | Sep 16 | Sep 9 – Sep 30 | 14–28 |
| Hydrangeas | Jan 27 | — | Apr 14 | — | Jun 23 – Oct 13 | 90–150 |
| Impatiens | Feb 10 | — | Apr 14 | — | Jun 23 – Oct 13 | 60–75 |
| Irises | — | Division | Apr 14 | — | Jun 2 – Jul 7 | 60–100 |
| Larkspur | — | Mar 10 | — | Aug 12 | May 19 – Jul 28 | 60–90 |
| Lavender | Feb 3 | — | Apr 21 | — | Jun 30 – Sep 8 | 90–120 |
| Lilies | — | Division | Apr 14 | — | Jun 23 – Oct 13 | 70–120 |
| Lobelia | Feb 3 | — | Mar 17 | — | May 12 – Aug 4 | 70–80 |
| Lupine | Feb 10 | Apr 14 | Apr 14 | — | Jun 2 – Jul 7 | 75–100 |
| Marigolds | Feb 24 | Apr 7 | Apr 7 | — | Jun 2 – Sep 8 | 50–70 |
| Nasturtium | Mar 10 | Apr 7 | Apr 7 | — | Jun 2 – Oct 6 | 55–65 |
| Pansy | Jan 27 | — | Apr 7 | Aug 12 | Jun 2 – Aug 11 | 70–90 |
| Peonies | — | Division | Apr 14 | — | Jun 9 – Jul 14 | 90–120 |
| Petunia | Feb 10 | — | Apr 14 | — | Jun 23 – Oct 13 | 70–90 |
| Phlox | Feb 3 | Apr 14 | Apr 14 | — | Jun 23 – Sep 15 | 80–110 |
| Portulaca | Mar 10 | Apr 7 | Apr 7 | — | May 26 – Sep 22 | 50–70 |
| Ranunculus | — | — | — | Aug 26 | Sep 23 – Oct 21 | 90–120 |
| Roses | Jan 27 | — | Apr 14 | — | Jun 23 – Oct 27 | 90–180 |
| Salvia | Feb 10 | — | Apr 7 | — | Jun 16 – Oct 6 | 70–90 |
| Sedum (Stonecrop) | Feb 3 | — | Apr 14 | — | Aug 4 – Oct 27 | 60–90 |
| Snapdragon | Jan 27 | Mar 10 | Apr 7 | Aug 26 | Jun 16 – Sep 8 | 70–100 |
| Sunflower | Mar 17 | Apr 7 | Apr 7 | — | Jun 30 – Oct 6 | 70–100 |
| Sweet Alyssum | Feb 24 | Mar 10 | Apr 7 | Sep 9 | May 19 – Aug 11 | 45–60 |
| Sweet Pea | — | Mar 3 | — | Aug 26 | May 12 – Aug 4 | 65–85 |
| Tulips | — | — | — | Sep 16 | Sep 2 – Sep 23 | 15–30 |
| Vinca (Annual) | Jan 27 | — | Apr 7 | — | Jun 16 – Oct 6 | 70–90 |
| Yarrow | Feb 3 | Apr 7 | Apr 14 | — | Jun 16 – Oct 27 | 60–90 |
| Zinnia | Mar 10 | Apr 7 | Apr 7 | — | Jun 16 – Oct 6 | 60–70 |
Monthly Planting Guide for Simpson
ZIP Codes in Simpson
Click any ZIP to see its specific frost, soil, and climate measurements (some ZIPs differ noticeably from the town aggregate):
Gardening Guides & Resources
Helpful guides from The Ultimate Homestead to improve your garden in Johnson County.
Your Johnson County Garden Planner — Free
A 22-page printable planner built for Johnson County (Zone 7a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.
The Gardener's Encyclopedia to Companion Planting
The pairings that make vegetables, herbs, and flowers grow better — and the ones that quietly wreck a bed.
- Proven pairings for 200+ vegetables, herbs, flowers, and fruits
- Full seed-starting + planting schedule with timing and spacing
- Bonus: square-foot gardening guide + printable seasonal planners
Seed Saving & Storage Guide
Most saved seeds go bad before next season. This shows exactly when to pick, how to dry, and where to store seeds from 200 plants so yours don't.
- 200 plants, step-by-step: life cycle, pollination type, isolation
- Exact temperature + humidity ranges that keep seeds viable
- Bonus: searchable Google Sheets tracker + custom GPT assistant
Composting Guide for Homesteaders
Turn kitchen scraps and yard waste into compost that actually feeds the garden — instead of a pile that smells, attracts pests, and never breaks down.
- 14 sections on composting methods, soil science, and troubleshooting
- The 7-step hot-compost system from start to finish
- Bonus tools: troubleshooting chart, safety guide, monitoring log