Growth and early fruit production of ‘Tiben’ blackcurrants fertilised with pre- and post-planting applications of mineral fertilisers and swine manure

• Blackcurrants were fertilised with swine manure and mineral fertilisers.
• Pre-planting use of manure or P and K fertilisers, and post-planting use of N fertiliser.
• Effectively improved fruit production.
• Yielding corresponded to plant growth.
• Foliar feeding had no effect on plant productivity and fruit quality.

The aim of the study was to examine the effects of different fertiliser strategies on the growth and fruit production of ‘Tiben’ blackcurrants (Ribes nigrum L.). The trial was performed under controlled greenhouse conditions from 2007 to 2010 on plants grown in 50-L polyethylene bags filled with a coarse-textured soil that was low in organic matter and available phosphorus (P) and potassium (K). Prior to planting, the soil was mixed with either superphosphate and potassium sulphate fertilisers at rates of 0.7 g P and 2.8 g K per plant or with solid swine manure at a rate of 300 g per plant, which was equivalent to 170 kg nitrogen (N) per ha. After planting, the plants were fertilised with either ammonium nitrate at rates of 1.3–2.0 g N plant−1 per year or with swine manure each year at the same amount as used prior to planting. Another treatment group was fertilised with manure prior to planting and ammonium nitrate after planting and was fertilised each following year with a complete foliar fertiliser. Plants grown without fertiliser or manure were also included as a control. The control plants had the lowest root dry weight, while the plants fertilised with any combination of mineral fertiliser had a greater root dry weight than those grown with manure only. Plants supplied with mineral fertilisers also had stronger vigour, higher photosynthetic rates, more chlorophyll in the leaves, and greater yields than did those grown with manure only or no fertiliser. Each fertiliser treatment increased the concentration of N, P, K, and magnesium (Mg) in the leaves relative to the control, and all but the concentration of leaf K was highest in the plants supplied with foliar fertiliser. The fertiliser treatments increased the soluble solids concentration and acidity of the fruit each year but resulted in lower berry weights than the control treatment during the fourth year of the study (2010). Fruit anthocyanins were not affected by any fertiliser treatment. Overall, the plants had the strongest growth and highest fruit production when P and K fertilisers or swine manure was applied prior to planting, and N fertiliser was applied each year after planting.