1. Soil Chemistry Acidifying the soil or lowering the pHAcidifying the soil or lowering the pH –Elemental sulfur (effect is temporary) –Ammonium sulfate (effect is temporary) –Aluminum sulfate is also used but not recommended as aluminum is a heavy metal!

2. Soil Chemistry Basic soils often can cause iron chlorosis in plants Basic soils often can cause iron chlorosis in plants This can be corrected by acidifying the soil This can be corrected by acidifying the soil or choosing a plant which is tolerant of or choosing a plant which is tolerant of alkaline soils! alkaline soils! Intervienal chlorosis: often on acid-loving plants like roses, fruit trees, acid-loving plants like roses, fruit trees, azaleas and rhododendrons azaleas and rhododendrons

6. Blue in acidic soils <5.5 with available aluminum with available aluminum Pink in neutral soils near pH of 7

8. Soil Fertility 16 elements required for plant growth16 elements required for plant growth C HOPKNS CaFe Mg B Mn CuZn Mo ClC HOPKNS CaFe Mg B Mn CuZn Mo Cl “C. Hopkins Café managed by mine cousins Mo and Cleo”“C. Hopkins Café managed by mine cousins Mo and Cleo”

9. Soil Fertility C, H, O from the atmosphere & waterC, H, O from the atmosphere & water Macronutrients: N, P, K most often deficient in soils. Also, S, Ca, MgMacronutrients: N, P, K most often deficient in soils. Also, S, Ca, Mg Micronutrients: Fe, B, Mn, Cu, Zn, Mo, ClMicronutrients: Fe, B, Mn, Cu, Zn, Mo, Cl

10. Soil Fertility

13. Not fertility, excess light!

14. Soil Fertility

16. Organic fertilizersOrganic fertilizers –The only choice up until the 1940’s –Manure –Fishmeal –Seaweed –Bloodmeal –Bonemeal –Cottonmeal –Sewage sludge –These often contain micronutrients