Symptoms
Symptoms begin at mature leaves. Leaves are dark green and a bit smaller than normal. With ongoing phosphorus deficiency leaf blades show a purple tint. Tinting becomes brighter as leaves age and approach early senescence. Fruits and flowers tend to be smaller and fruits can develop albinism.
Causes
Phosphorus deficiency
Petioles of phosphorus deficient leaves contain less then 700ppm acetic acid soluble phosphate-phosphorus, dry basis.
Strawberry (field grown): Non-everbearing varieties, 3 applications of 10 l/ha from start of flowering. Repeat applications at 7-10 day intervals. Everbearing varieties, divide a total rate of 30 l/ha into 6 applications of 5 l/ha. Do not apply successive applications at intervals of less than 10-14 days. Water rate: 500 l/ha.
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