Focus On Fertilizer: Micronutrients And Organics
Fertilizer companies are making it easier for growers to balance fertility programs in ornamental crops and even begin to delve into vegetable and herb growing. New products are focusing on micronutrients and providing efficient options for organic production.
Liebig’s Law of the Minimum states that plant growth is always limited by the lowest level of each essential nutrient. Consequently, one of the keys to successful fertility programs is to make sure plants have access to limiting nutrients that obstruct healthy growth.
In Addition to N, P And K
A number of new products are available to help greenhouse growers manage fertility beyond standard macronutrients.
“While growers pay attention to nitrogen (N), phosphorus (P) and potassium (K), they sometimes ignore important secondary and micronutrients like magnesium and iron,” says Fred Hulme, technical services director for Everris. “These are critical to the success of a plant nutrition program and need to be provided in the right amounts and at the correct time for optimal crop quality and value. Many common crop nutrient deficiency symptoms are due to shortages of these neglected elements or issues related to root zone pH.”
One of Everiss’ formulations, Liquid S.T.E.M., is a chelated and complete complex of micronutrients that allows growers to customize their micronutrient programs and provides a broad micronutrient rescue option for stressed plants.
Jack’s Professional 18-2-18 Boosted Base FeED, from J.R. Peters Inc., is designed for use at lower feed rates (125 ppm), when there is ample calcium in the water source. The formula has two times the overall micronutrient package and the most current chelate blends to keep micronutrients available at higher pHs.
“We noticed growers were trying to save money and be more efficient by reducing overall fertility rates,” says Cari Peters, vice president at J.R. Peters. “We observed that there are not as many macronutrient deficiencies at this lower rate, but rather more secondary and micronutrient deficiencies as the overall feed rate skims the lower limit of trace element thresholds. With Jack’s Professional, growers can feed less on a constant liquid feed or period program while still delivering enhanced micronutrient levels to the plant.”
Plant Probiotic from Nature’s Source is not a true fertilizer, but it is designed to establish beneficial microbial populations that provide the soil with the necessary components to promote healthy plant growth and reduce stress. The beneficial microbes in Plant Probiotic can aid in the assimilation of raw nutrients, provide protection from pathogenic microbes and extend plants’ ability to access water and nutrients, according to Janet Curry, national sales manager for Nature’s Source.
Mark T. Jeffries, vice president of Masterblend International, suggests letting the plant be the final judge when determining if nutrients are effective. Measuring nutrients in soil or media only tells a grower if nutrients are available for the plant to take up. Plant analysis is one of the best ways to determine if the plants are utilizing available nutrients, he says.
Ann Molloy of Neptune’s Harvest agrees. “My advice is to run some small tests to see what works best before going with a full-year program,” she says. “Growers can then move forward with confidence for the growing season.”
Bringing Silicon To The Forefront Of Plant Nutrition
For years, Dyna-Gro Nutrition Solutions has offered products like Foliage Pro and Liquid Grow, which include all six macronutrients and the 10 essential micronutrients. More recently, the company has been concentrating on a lesser-known element — silicon.
Pro-TeKt, The Silicon Solution (0-0-3), provides supplemental potassium and silicon.
“Silicon provides a wide range of benefits to plants,” says Dave Neal, CEO of Dyna-Gro. “It improves resistance to a variety of environmental stresses and stimulates root growth.”
“Silicon helps compensate for what would otherwise be toxic or deficient levels of a variety of minerals. It makes plants more heat-, drought- and cold-tolerant and increases fertility. Flowering plants have larger, longer-lasting blooms and fruiting plants produce more abundantly.”
For best results, Dyna-Gro recommends using both Foliage-Pro and Pro-TeKt. The two concentrates cannot be mixed. However, they may be combined at application through injection into separate irrigation lines.
The Rise Of Organics
The increased interest in growing herbs and vegetables has naturally led to a renewed interest in organic fertilizers. However, growers choosing to go organic must carefully consider their options, which may be limited.
“When growers choose the organic option for feeding container-grown vegetables and herbs, they are limiting their access to available fertilizer technologies,” Hulme says. “There are very few truly organic [e.g., Organic Materials Review Institute (OMRI)-certified] products available for container production. A number of products on the market are labeled as ‘organically based’ but these are combinations of organic and synthetic components.”
When using organics, growers need to match their fertilizers with the nutrient needs of the crop, which can mean using more than one fertilizer in a program, according to Matthew Krause of BioWorks Inc. BioWorks has several new organic and organic-based products out for greenhouse use under its Verdanta line. One of which is Eco-Vita 7-5-10, an OMRI-approved product that provides longer-lasting continuous action for 75 to 100 days.
Ann Molloy of Neptune’s Harvest says growers can benefit from organic fertilizers that offer more than just N, P and K. Neptune’s organic Fish/Seaweed blend includes natural growth promoters and micronutrients that help compensate for lower NPK rates. Other products like Crab Shell provide added calcium and magnesium.
The Next Generation Of Composting
WISErg, based out of Redmond, Wash., is involved in a unique form of organic conversion, one that turns food scraps — leafy greens, vegetables, coffee, even meat products — into a nutrient-rich liquid fertilizer. It all starts at the site of food scrap generation.
“We are initially working with grocery stores and commercial kitchens because they have a high volume of food scraps that are relatively clean for processing,” says Tim Robie, WISErg’s fertilizer engineer. “The current disposal alternatives to these businesses are costly and have a negative environmental impact in contributing to landfill volumes generated from our urban populations.”
Employees enter a security code and dump the food scraps in WISErg’s Harvester unit. The unit categorizes the food type, weighs the material, then prepares it for a biological conversion. The converted material, now a liquid-based biomass grown from food scraps, is ready for transport to a central refinery. WISErg is stringent about monitoring and documentation to ensure traceability and to comply with EPA 503 regulations.
WISErg recently teamed up with the University of Arizona to see how its products compared to conventional ones during lettuce, broccoli and kale production in a sand bed culture.
“We found we were able to match yields with the conventional program,” Robie says. “To be able to match yields on short-season crops with our organic fertilizer is a testament to our material’s rapid mineralization and to the fact that organics can yield as much as conventional products.”
WISErg currently offers two water-soluble formulations under its WISErganic line, and both are pending OMRI-certification. The company has new products in development that will combine its base formula with additional macro and micronutrients for a complete nutrition package. It is also recruiting volunteers for the 2014 WISErg Farm Team to provide grower-feedback on WISErg’s current products and to work closely on ongoing product development.