Tomatoes are Bulgaria's most fertilised — and most wrongly fertilised — crop. The official tech cards are clear if read by stage: P and K banked before planting, phosphorus-heavy starter at transplanting, potassium-dominant formulas from flowering onward, peaking through fertigation during fruiting. The established optimal ratio is N:P2O5:K2O = 1:0.8:0.4.
Blossom-end rot is not a disease: it is localised calcium deficiency, fixed by regular calcium nitrate through fruiting and even drip irrigation, never by fungicides. The costliest mistake is extra nitrogen — Bulgarian institute trials show excess mineral N lowers dry matter, sugars and vitamin C, with a balanced seasonal total around 30 kg N/da on the trial soils, split across the season. Unsure what a symptom means? Upload a photo to Zemedelko — the AI tells deficiency from disease before you pay for the wrong fix.