Chempak organic Organic potato fertiliser A specially formulated granular fertiliser packed full of essential nutrients for growing potatoes, in the correct balance, slowly released throughout the season to provide tastier and increased yields of quality homegrown potatoes. Perfect for growing direct outdoors, in containers outdoors or under protection, or in the greenhouse. Can also be used as a general fertiliser for other vegetables. (N:P:K - 4-6-12 +4MgO) 750g is sufficient for planting 4 x 2.5m (8ft) rows of potatoes.