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- Slide to your soil pH and see which crops match it
- Exactly what to add to move it, and how much
- Your zone and results remembered next time
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What soil pH means
pH runs from 0 (acidic) to 14 (alkaline), with 7 neutral. It doesn't feed plants directly — it controls whether the nutrients already in your soil are available to them. Get the pH wrong and you can pour on fertilizer while plants still starve, because they can't take it up.
The vegetable sweet spot
Most vegetables are happiest at pH 6.0–7.0 — slightly acidic to neutral. If your garden sits in that band, you rarely need to adjust: feed the soil with compost and leave the pH alone.
Shifting your pH
| Situation | What to do |
|---|---|
| Too acidic (low pH) | Add garden lime (calcium carbonate). Work it in during fall so it has time to act. |
| Too alkaline (high pH) | Add elemental sulfur, or work in peat / pine-needle compost. Go slowly and re-test. |
| Any change | Move in small steps over seasons — big swings shock the soil life. Re-test before adding more. |
Plants that want it acidic
A few crops break the rule and want it distinctly acidic: blueberries (4.5–5.5) most of all, plus raspberries, blackberries, and potatoes (lower pH also suppresses scab). Give these their own bed so you can acidify just that spot.
Test each spring
Soil pH drifts, so test in early spring before planting. A cheap home kit gets you close; your county extension office runs a proper lab test for a few dollars and tells you exactly how much lime or sulfur to add.