Soil:

Sand/Humus

Potato variety:

Timo (New Potato)

Drip irrigation:

1,5% Allgrow

Results:

Increase of harvest + 31,20%

Potato tubers had a nice color and feelt very healthy and fresh

Similar results can probably be achieved with 6-8 sprays.

Source:

Oy Schetelig together with potato farmer.