Optimising water solubles in a wet year

With several factors conspiring to reduce nutrient levels in ornamental crops this season, ICL technical manager – Andrew Wilson – urges growers to reassess their water soluble fertiliser options and application rates as appropriate.

“This year nutrient leaching is a particular issue due to the high rainfall,” he says. “Pale leaves, caused by Nitrogen (N) deficiency, is the most common symptom we’re seeing on nurseries. While generally more commonplace, as growers reduce their peat usage – wood-based materials can cause N lock-up and have a lower nutrient buffering capacity – heavy rainfall has compounded the issues.

“During June, plant growth peaks generating high demand for this important macronutrient.  This season outdoor crops have not needed irrigating so often, significantly reducing fertigation opportunities. In protected crops, high humidity means pots have not dried out as quickly. To avoid raising humidity levels further, creating conditions ideal for fungal diseases, growers have been keen to minimise irrigation.”

“For outdoor crops and well-ventilated protected crops, foliar feeds are a useful option.  Offering high purity, fast-acting Peters Professional Foliar Feed can be applied to foliage at a rate of 2g/litre – greening up stock quickly.

“Growers using traditional fertigation can switch between Universol products depending on the crop’s growth stage or issue. For example, Universol Green (NPK ratio 4:1:2) contains high N to boost growth; Universol Blue (3:2:3) is well-balanced for mid-season growth; Universol Orange (3:1:5) promotes slower growth and flowering; and Universol Violet (2:2:6) promotes compact and strong growth.

“Quality water solubles, with high purity, can be used at higher concentrations – ideal when there are fewer fertigation opportunities. For Universol the recommended daily fertigated rate is 1/400. However, if less frequent, this concentration can be raised to 1/200 and ultimately to 1/100, to give the crop a particular boost.”

To help growers navigate its extensive Peters and Universol ranges, ICL has produced a timely series of new animated videos.

For more information on Peters Excel – delivering complete plant nutrition using a single-concentrate stock tank while taking in account the quality of the irrigation water – more information: CalMag range and Acidifier range.  You can find the Universol Soft and Hard water products here.