Foliar feeding the Omex way – it’s time for tea! By Dr Terry Mabbett

Tea (Camellia sinensis) is native to a large area of East Asia but as a crop tea is grown throughout the world where climate allows.  Turkey is in the top five world producers with 250,000 tonnes per annum. Turkish people drink more tea per person than in any other country of the world. Tea is also grown in East and Southern Africa with Kenya, Uganda and Malawi as key tea-producing countries.

As an evergreen bush crop with routine picking of young shoots and leaves tea requires full and fast nutrition by foliar feeding says Omex Agrifluids, a world leader in the design, development and delivery of soluble nutrient products.

Assam in North-East India, the world’s largest tea growing region by production, is just one of regions where a comprehensive range of Omex products is used to maintain plant vigour and vitality of the world famous Assam black tea leaf infusion. Tea growers on estates across Assam use the following combination of Omex products.

Omex Bio 20 – A formulation of macronutrients, magnesium + iron and chelated micronutrients all ‘wrapped up’ with a natural biostimulant sourced from seaweed. Omex Bio 20 is applied as a foliar spray. Omex Bio 20 is used first in the tea nursery to promote root biomass for maximum uptake and utilization of water and nutrients. Follow up applications to young tea bushes help to alleviate physiological stress caused by abiotic and biotic factors including high temperature, soil moisture deficit and pest and disease attack. Mature tea bushes benefit from Omex Bio 20 through enhanced plant health and vigour translating into higher yields of better quality leaf.  As a foliar-applied spray Omex Bio 20 is effective during the wet season when soils are water-logged and root absorption is inhibited.

Omex Kingfol Zn – A high analysis liquid suspension containing 70% zinc (w/v) and used for rapid correction of zinc deficiency which is common in tea growing regions, including Assam, because zinc becomes locked up in the soil. Recommendation is 0.25 to 0.5 L/ha in a foliar spray depending on severity of zinc deficiency. Regular use reduces the incidence of ‘banjhi’ buds, a pair of leaves enclosing a dormant (inactive) bud or no bud at all. Omex Kingfol Zn outperforms standard foliar spray applications of zinc sulphate (Zn SO₄) especially during attacks of red spider mite (Oligonychus coffeae).

Omex Foliar Boron – A high analysis solution of boron (15% w/v) is used to boost recovery from attacks by tea mosquito bug (Helopeltis theivora) and/or to correct boron deficiency. Recommended rate is 0.5 to 0.6 L/ha as a foliar spray applied immediately after attack by tea mosquito bug and at the first sign of deficiency symptoms. Omex Foliar Boron is the ideal ‘rehabilitation’ spray for tea.

Omex K41 – This is a water soluble emulsion of macronutrients and sulphur containing an ultra-high (40% w/v) concentration of potassium.   Potassium the so-called ‘gatekeeper’ nutrient is crucial for maintaining optimal plant water relations. Foliar application of Omex K41 improves tea leaf turgidity to produce heavier harvests of picked leaves and shoots. Omex K41 is especially useful when tea is grown on sandy substrates where soil water deficits are most pronounced.  

Omex Seastar F – Seastar F is a natural seaweed-derived growth stimulation product containing a range of physiologically active compounds including amino acids and plant hormones. Foliar applications assist in breaking bud dormancy especially during dry periods, thus boosting growth of new shoots for heavier harvests of leaves.

Omex Kingfol Mg – This is another product from the Omex Kingfol range and containing 22% magnesium (w/v), which is the metallic element at the core of the chlorophyll molecule. Under plant stress conditions tea leaves become hard and fibrous and unsuitable for picking. Application of Kingfol Mg as a foliar spray helps to soften the leaves while heightening leaf colour by enhancing chlorophyll content for improved photosynthesis and yield.

Omex Kingfol S – Kingfol S with 72% sulphur (w/v) improves the green colour and shine of tea leaves to give measurable increases in yield. The sulphur in Kingfol S also hones quality of the black tea infusion because sulphur is a key constituent of the chemicals responsible for colour, taste and aroma.

Omex  3X Emulsion – A fully water-soluble fluid fertiliser containing macronutrients and chelated micronutrients with magnesium and iron. Foliar feeding with Omex 3X Emulsion improves chlorophyll content of leaves for bigger and faster breaking leaf buds and enhanced leaf colour. The improved plant vigour alleviates soil-associated stress whether from waterlogging or drought.

The End09 February 2021