January
- Order seed. Dream less; plan bed layout and drip lines more.
- Start onion seed indoors if you’re that person (most people buy sets/plants—fine).
- Inventory fertilizer, mulch, row cover. January you is doing summer-you a solid.
Seasonal planting calendar
Built for Kennewick averages: last frost ~mid-April, first frost ~mid-October. Your yard is not a USDA spreadsheet. If the weather app says freeze, believe the app—not your optimism.
Pro tip for the chronologically gifted: “Plant after Mother’s Day” is a western-WA meme.
Here, many warm crops can go out late April to early May if soil is warm and frost risk is low.
Cold soil + early transplant = stunted plants that never catch up. Patience is free. Dead starts are not.
| Crop | Start indoors | Transplant / sow out | Main harvest window |
|---|---|---|---|
| Onions (sets/plants) | Optional seeds: Jan–Feb | Mar–early Apr (as soon as soil workable) | Jul–Sep (bulbs); greens earlier |
| Sweet corn | Usually direct sow | Late Apr–mid Jun (soil ≥60°F) | Jul–Sep (by planting date) |
| Bell peppers | 8–10 wks before transplant (~late Feb–Mar) | Late Apr–mid May (warm nights) | Jul–Oct |
| Jalapeños | 8–10 wks before transplant | Late Apr–mid May | Jul–Oct |
| Basil | 4–6 wks before transplant | After frost risk; nights preferably >50°F | Jun–first hard frost |
| Zucchini | Optional 2–3 wks; or direct sow | Late Apr–Jun (soil ≥60°F) | Jun–Oct (continuous) |
February
- Start peppers (bell & jalapeño) indoors under lights—not a dark windowsill that faces a dumpster.
- Test soil if you haven’t. Alkaline Basin dirt will not magically become loamy compost by wishing.
- Prune nothing vegetable-related. There is nothing. Sit down.
March
- Onions: plant sets/transplants when soil is workable—often mid-to-late March here.
- Continue pepper seedlings; pot up if roots circle the cell like sad prisoners.
- Start basil indoors late month if you want early pesto. Harden off later—don’t skip that step.
- Amend beds with compost. Work soil only when it’s crumbly, not mud pie.
April
- Average last frost ~mid-month. Still: watch the forecast like it owes you money.
- Corn: first sowings late April if soil ≥60°F. Plant in blocks, not one sad row.
- Zucchini: late April direct sow or transplant once soil is warm.
- Peppers & basil: harden off; transplant late April only if nights are cooperating.
- Install drip. Mulch after soil warms a bit so you don’t keep beds cold forever.
May
- Main transplant month for peppers, jalapeños, basil. Soil should feel warm to the hand.
- Succession corn every 10–14 days if you want ears all summer, not one chaotic weekend of corn.
- Onions: keep evenly moist; side-dress nitrogen if growth is pale and slow.
- Wind protection for new transplants. Stakes, cages, or temporary covers—pick one.
June
- Last corn plantings early–mid June for late ears before frost roulette.
- Deep water as heat ramps. Daily misting is performance art, not irrigation.
- Pinch basil tops; harvest zucchini small and often.
- Watch for aphids on peppers and squash bugs on zucchini. Ignore pests only if you enjoy losing.
July
- Peak heat. Mulch depth matters. Irrigation timers matter. Your “I’ll check after work” plan will fail once.
- Peppers flowering/fruiting—steady water + balanced feeding; don’t flood then drought them into blossom drop.
- Corn tasseling/silking: water is non-negotiable. Dry silk = empty tips = your failure made edible-looking.
- Harvest jalapeños green or wait for red if you can wait five minutes for once.
August
- Still irrigating. Still harvesting. Still not “done for the year.”
- Onions: tops fall over—stop watering heavy, let bulbs finish, then cure.
- Basil: keep pinching flower spikes unless you want a seed factory with cardboard leaves.
- Order cover crop seed if you want bare beds to stop looking like a dust bowl.
September
- Harvest remaining summer crops. Pick peppers before cool nights stall ripening.
- First frost can flirt mid–late October—but cold nights start earlier. Row cover is cheap insurance.
- Clean spent zucchini plants if disease is ugly. Don’t compost plague unless you enjoy sequels.
- Cure and store onions properly or watch them rot in a damp garage like a science project.
October
- Average first frost window. Pull tender crops (basil dies first—always).
- Final pepper harvest. Green bells still count as food. Lower your standards productively.
- Clear beds, add compost, mulch empty soil so wind doesn’t gift your topsoil to Benton City.
- Drain drip lines if freeze risk warrants it. Plastic fittings hate surprise ice.
November–December
- Garden is mostly offline. Tools clean. Hoses stored. Ego recovered.
- Review notes: what died, what thrived, which bed was a wind tunnel.
- Plan next year’s crop rotation. Don’t plant onions where onions just were if you can help it.
- Read the crop guides again before you buy 47 pepper varieties in January. Restraint is a skill.