Jm. Njoroge et E. Mwakha, INFLUENCE OF NITROGEN-FERTILIZER AND PLANT-DENSITY ON GROWTH AND YIELD OF ARABICA COFFEE DURING THE 1ST PRODUCTION CYCLE IN KENYA, Discovery and innovation, 5(3), 1993, pp. 235-239
Field interactions between nitrogen rates of application from 0 to 400
kg N/ha/yr and three coffee tree densities, 1329, 2658 and 5320 trees
/ha, were evaluated during the first production cycle after establishm
ent in Kenya. Application of more than 50kg straight N/ha/yr at Ruiru
(east of Rift Valley) and Koru (west of Rift Valley) did not give sign
ificantly higher yields of clean coffee regardless of the tree density
evaluated. The lowest tree density of 1329 trees/ha produced signific
antly (p = 0.05) lower yields of clean coffee than the higher tree den
sities of 2658 and 5320 trees/ha. Clean coffee yield production was no
t significantly different among the higher tree densities of 2658 and
5320 trees/ha at Koru site. Proportions of the large grade ''A'' sized
beans were significantly (p = 0.05) lower in high nitrogen rates of a
pplication treatments. High density planted plots contained higher res
idual soil moisture content with thinner but taller coffee tree stems.
Productive wood was highest under the medium tree density of 2658 tre
es/ha.