A review of research on the fertiliser and lime requirements of pasture on the eastern coast of the North Island

The soils on the eastern region of the North Island (Wairarapa, Tararua, Hawke’s Bay, Poverty Bay, East Coast) are mainly of the Brown, Pallic, Recent (Sedimentary) and Pumice orders and are most are farmed with sheep and cattle on hill pastures. Several field trials have been carried out to determine the pasture growth requirements for phosphorus (P), sulphur (S), potassium (K), nitrogen (N), lime and molybdenum (Mo) in this region since the 1960s and the results published in various papers. This review considers the results of these studies collectively and in relation to national datasets. Sedimentary and Pumice soils with Olsen P levels of less than 12 µg/mL required annual application of P. Significant pasture production responses to S were measured where initial soil sulphate-S levels were less than 6 ppm. Additional K for sheep and beef pastures was required mainly on Pumice and Brown soils with soil QTK levels of 6 or less. Large pasture DM responses to N were measured in most trials, especially on steep slopes and sunny aspects with low legume content. Lime is needed to maintain soil pH once it decreases to 5.4 on hill soils. Molybdenum deficiency in legumes can occur on sedimentary soils and should be monitored by clover-leaf analysis.