18 August 1995

Injection boost for potatoes

INJECTING fertiliser boosts potato yield and baker fraction, according to a five-year project conducted by Harper Adams Agricultural College.

Potato plots injected with 200kg/ha (160 units/acre) of N, 100kg/ha (80 units/acre) of P and 300kg/ha (240 units/acre) of K yielded 58.8t/ha (23.8t/acre), just over 12% more than those treated with granules broadcast pre-planting.

Baker content rose by 43% to 16.46t/ha (6.66t/acre). At £80/t for ware and £135/t for bakers, which means an extra £800/ha (£324/acre). But the extra equipment needed costs just £22.50/ha a year for a 40ha (100-acre) crop.

The key is a more consistent nutrient and moisture supply giving a longer lasting canopy, says HAACs Jim Lewis.

"Nutrients are in exactly the right place for the crop. Roots pick up fertiliser as they grow down, rather than having to extend up to source granular fertiliser," adds Mr Lewis. &#42