Abstract:
Kenya’s tea industry depends predominantly on imported NPK fertilizers
to replenish nutrients removed through plucking. In this respect, two
blended fertilizers containing NPKS 25:5:5:4+9Ca+2.6Mg and NPKS
23:5:5:4+10Ca+3Mg with trace elements have been produced in the
country. However, contribution of the blended fertilizers to optimal
tea yields had not been determined. The study aimed to evaluate
the optimal levels of the two blended fertilizers on tea grown in the
highlands of Kenya. The blended fertilizers were evaluated in two sites,
i.e. Timbilil estate in Kericho and Kagochi farm in Nyeri. The trial
was laid out in a randomized complete block design with two blended
fertilizers and the standard NPK 26:5:5 as a control. The treatments
were applied at four fertilizer rates (0-control, 75, 150 and 225 kg N
ha-1 yr-1), with three replications. The results showed that application
of 225 kg N ha-1 yr-1 blended fertilizer NPKS 25:5:5:4+9Ca+2.6Mg in
Timbilil produced mean yield of 2,995 kg Mt ha-1 compared with 3,099
kg Mt ha-1 from the standard NPK. In Kagochi, the highest yield was
1,975 kg Mt ha-1 obtained from the application of the same blended
fertilizer NPKS 25:5:5:4+9Ca+2.6Mg at 75 kg N ha-1 yr-1. The highest
yields in both sites were obtained during a warm-dry season except
in 2015–2016. This study concluded that based on the annual and
seasonal yields, the two blended fertilizers and the standard type had
the same effectiveness, irrespective of clones and sites. However, the
fertilizer rates affected the tea yield.
