Boron Deficiency in Shade Trees for Tea

Without sufficient boron, shade trees can suffer dieback, malformed leaves, cracked bark, and excessive side-shoot growth. Silver oak trees can also suffer necrosis of the cambium.

Dadap

Erythrina variegata

The youngest dadap leaves are the first affected when the plant is boron deficient:

  • The pinnae are small
  • Many segments do not develop, resulting in the formation of a very simple leaf

As the deficiency progresses, the growing points die back followed by the development of many shoots from the main trunk. Bark cracking and gum exudation occur when the deficiency is very advanced.

Necrosis of the cambium has been reported.


Silver oak

Grevillear robusta

Boron deficiency in silver oak causes dieback and multiple side shoot development. The leaves are blunt, in marked contrast to healthy pointed leaves.

U.S. Borax products for shade trees for tea

15% Boron |  | OMRI Certified
Fertibor
Optimum product for suspensions

A fine crystalline borate ideal for NPK compound fertilizers and suspensions. Manufactured as free-flowing granules, Fertibor is easily handled and offers superior flow and consistency.

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15% Boron |  | OMRI Certified
Granubor
Made especially for bulk blenders

A pure, 100% water-soluble micronutrient that meets boron demand during the growing season. Made especially for bulk blenders, Granubor helps to ensure uniform distribution in nutritional blends and in the field.

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20.5% Boron |  | OMRI Certified
Solubor
Product of choice for foliar applications

A concentrated, highly soluble, and fast dissolving powder that is ideal for foliar and other sprays. With the highest concentration of boron in any approved product, Solubor is an economical choice for nutritional formulations.

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11% Boron (w/w)
Liquibor
Liquid boron from boric acid

The convenience of liquid boron fertilizer straight to your farm with no measuring or mixing required.

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10% Boron |  | OMRI Certified
Solubor Flow
For fertigation or hydroponic growing

First and only aqueous suspension of sodium borate microcrystals.

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14.5% Boron | 29% Zinc
Zincubor
Perfect combination of zinc and boron

Because zinc and boron deficiency are widespread around the world, a product with both nutrients is a good fit in many regions. Zincubor brings these two important micronutrients together in one product.

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U.S. Borax, part of Rio Tinto, is a global leader in the supply and science of borates—naturally-occurring minerals containing boron and other elements. We are 1,000 people serving our customers with more than 1,200 delivery locations globally. We supply around 30% of the world’s need for refined borates from our world-class mine in Boron, California, about 100 miles northeast of Los Angeles.

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