Chrysanthemum and Pyrethrum

{Chrysanthemum spp.}

Boron Deficiency in Chrysanthemum and Pyrethrum

In mild cases of boron deficiency, the petals fail to unroll properly and become “quilled." When the deficiency is severe, you will see symptoms in the leaves which are brittle and closely spaced. Some down-curling of the leaves may occur and leaf tips may become chlorotic. There may be some loss of flower color. When the boron deficiency is acute, the buds fail to open properly. Growing point death is followed by multiple shoot formation.

Boron deficiency in pyrethrum causes the development of misshapen and malformed flowers and apical dieback in pyrethrum. Ray florets may be reduced to one third their normal length. They have ragged tips and they may be formed on only part of the circumference. In some cases, ray florets may be completely absent.

Soil Application (Suggested rates of application)

  Granubor Fertibor
LBS/ACRE 3-13 3-13
KG/HA 3.38 - 14.63 3.38 - 14.63

Foliar Application (Suggested rates of application)

KG/HA 2.25 - 2.25
Value in Use
Current Yield (Per Acre)
Expected Sale Price

Spotting a Boron Deficiency

Malformed petals due to quilling, a common symptom of boron deficiency.

Spotting a Boron Deficiency

Two small, quilled florets on the right.

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