Jul 15, 2015 · borax and pc fertilizers were equal in efficiency because of the longer time in the soil pc was able to supply sufficient b to the crop. as our soil incubation study showed that with the passage of time b release from pc was equivalent to borax. these results are consistent with the findings of rashid et al. The ideal release should be slow enough to protect against leaching and toxicity, but fast enough to supply essential nutrients to plants when needed. solubility of solubor in liquid fertilizers solubor is an excellent boron source for inclusion in liquid fertilizers because it is readily soluble and does not react with other components of th... 2, quick dissolve, this product dissolves quickly, the speed of dissolving in water at 0°c is 2.2 times higher than that of borax, 3.67 times at 20°c, 5.61 times at 30°c, it can avoid the phenomenon of scorching hot on the leaves that is caused by not well-distributed dissolving. 3, fast absorbing, according to the experiment,... Borax decahydrate and borax pentahydrate are most widely used borates as boron fertilizer. sodium borates can be used as soil application and also as foliar application due to its high solubility. colemanite which is a naturally occurring calcium borate is used especially in sandy soils as a slow release fertilizer which provides constant supply of available b in the soil.