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Hydrangeas — in-ground bed (Hortensia)

ornamental_acid_loving_in_ground_shrub · Hydrangea macrophylla (presumed — common in-ground species)

+ Spray + Water + Photo

Planned next action

Recipe: -

When: monthly cadence May-Sep, starting ~2026-06-15 · morning

Acid-loving plant in alkaline Riva soil — preventive Fe/Mg monthly + Al availability for blue bloom

Watering regime

Summer: every 2-3 days (acid-loving, prefer consistent moisture)

Cooler: weekly

Method: Stick finger 5 cm down at base — water if dry. Hydrangea wilts visibly when dry (drama queen — recover quickly with water).

Source: Rainwater or ionizer acidic preferred (acid-loving); tap OK in pinch

⚠ Phyto-watch (3)

2026-05-20 (post-Fe-drench day 2 observation) · moderate (Fe addressed via 2026-05-18 drench; awaiting recovery on new leaves)
Fe chlorosis observed across 4-5 hydrangea plants with varying severity (IMG_3348 worst, IMG_3349 mildest); IMG_3347 also shows brown necrotic spots = probable Cercospora leaf spot
→ (1) Wait 7-14 days for FERROS drench to show on new growth. (2) Optional accelerator: hydrangea-acid-loving-foliar-fe-mg-mn recipe next dry morning. (3) Remove + bag (not compost) Cercospora-spotted leaves from IMG_3347 plant. (4) Sonbahar elemental sulfur top-dress (2-4 kg/10m²) for long-term pH correction. (5) Switch watering to ionizer acidic/rainwater (no more raw tap).
2026-05-18 · ongoing maintenance
Riva soil pH 8.0 alkaline = permanent Fe lockout for in-ground hydrangea
→ FERROS EDDHA annual application: 3-5 g per plant in 2-5 L acidic water, soil drench around root zone, twice per year (early spring + early summer). True EDDHA stable in alkaline soil; single dose lasts 2-3 months. This is the long-term Fe strategy for in-ground hydrangea while sulfur amendments slowly correct pH.
2026-05-17 · moderate
In Riva pH 8.0 soil, hydrangeas may show Fe chlorosis over time and bloom pink regardless of variety
→ (1) Annual elemental sulfur top-dress 2-4 kg/10 m² for slow pH correction. (2) Foliar Fe chelate spray 2-3x per season for chlorosis prevention. (3) If blue blooms desired, apply aluminum sulfate (specific to hydrangea, ground around root zone) — and lower pH below 6.

Photos (0)

Sprays (2)

2026-05-18 TBD (with gardenia/pittosporum batch) · gardenia-chlorosis-prevention-Fe-Mg-Mn · foliar_complete pending observations
2026-05-18 evening (exact time TBD) · outdoor-potted-fe-drench-multi-zone-monthly · complete