Boron Deficiency in Hops
The growing points turn brown and may die when they are only a few inches long. The root stocks produce many shoots with short internodes, many of which will die, giving the plant a stunted, bushy appearance. Axillary buds on the shoots which survive may also become necrotic and die although some of the stunted lateral shoot eventually develop. Leaves produced on such shoots tend to be small, distorted and double toothed rather than lobed. Stipules develop normally at first but quickly become necrotic from the tip downward as they age. Many inflorescences turn brown and die. The cones that form are small, loose and have a scorched appearance which starts at the tip and progresses to the base. The yield is severely reduced. Root systems of deficient plants develop poorly.