Getting Started
Plant Nutrient Table
Macronutrients and micronutrients, typical dry-weight ranges, and organic sources. Read with Introduction to Fertilizers.
| Nutrient | What it does | Typical in tissue | Organic sources |
|---|---|---|---|
| Nitrogen (N) | Leaves, green color, growth | 2–5% dry weight | Compost, alfalfa, fish emulsion, blood meal |
| Phosphorus (P) | Roots, flowers, fruit, energy | 0.2–0.5% | Bone meal, rock phosphate, compost |
| Potassium (K) | Water balance, stress and flavor | 1–4% | Kelp, sulfate of potash, wood ash (sparingly) |
| Calcium (Ca) | Cell walls, growing tips | 0.5–1.5% | Lime (if pH is low), gypsum, eggshells (slow) |
| Magnesium (Mg) | Chlorophyll | 0.2–0.4% | Dolomitic lime, Epsom salts only if a test shows need |
| Sulfur (S) | Proteins, flavor in brassicas and alliums | 0.2–0.5% | Compost, gypsum, elemental sulfur |
| Iron (Fe) | Chlorophyll (trace) | 50–250 ppm | Compost; chelates if high pH locks it |
| Manganese (Mn) | Photosynthesis (trace) | 20–200 ppm | Compost; avoid overliming |
| Zinc (Zn) | Enzymes, growth points | 15–60 ppm | Compost, kelp |
| Copper (Cu) | Enzymes (trace) | 5–20 ppm | Compost — easy to over-apply |
| Boron (B) | Cell walls, fruit set | 20–60 ppm | Very little; compost usually enough |
| Molybdenum (Mo) | Nitrogen use in legumes | 0.1–1 ppm | Compost; more available at higher pH |
| Chlorine (Cl) | Osmosis (trace) | — | Rain and compost; never add as a “boost” |