SummaryA field experiment was carried out with one-year-old peach trees to determine the influence of applications of nitro-chalk (N), superphosphate (P), sheep manure (SM), and a fertilizer mixture (X), in factorial combination, on tree growth during the first growing season. Fertilizers were mixed into the soil at planting sites about two weeks before tree planting.Maximum tree growth was achieved when 3 lb. P and 36 lb. SM were applied per tree. However, all fertilizers depressed leaf bud development and early shoot growth and, in a few cases, application of 3 lb. N per tree resulted in tree death. It is concluded that heavy rates of these fertilizers should not be applied to planting sites prior to planting young peach trees. Rather, it appears from seasonal growth measurements that fertilizers should not be applied to newly planted trees until late spring (November).The only consistent and significant interaction occurred between N and SM. Application of SM increased tree growth more in the absence of N than in its presence; i.e. the SM acted as a nitrogen source. SM depressed tree growth early in the growing season, probably because some of its components are readily soluble. However, later in the season it promoted growth and partly alleviated the detrimental effect on tree growth induced by 3 lb. N per tree. It is evident from calculated concentrations of elements per planting site that the SM treatment supplied larger quantities and a wider range of elements than the inorganic fertilizers.In the absence of an N × SM interaction trees grew better if given nil or 1 lb. N than if they were given 3 lb. N. For some growth parameters, trees also grew significantly better if given 1 lb. N rather than nil.Application of a fertilizer mixture containing potassium sulphate, magnesium carbonate, lime, ammonium molybdate, zinc sulphate, borax, Chel-138 iron chelate, and manganese sulphate to planting sites significantly depressed tree growth throughout the growing season, but this may have been due to molybdenum toxicity, although no visual symptoms were present.