September 16, 2009

Understanding Plant Nutrition: Stock Plant Nutrition

Nutrient management for stock plants is similar to other long-term crops. We have worked with several leading stock plant growers both in the United States and overseas over the past decade. Together, we have found the keys for success are fairly straightforward: have an organized plan that includes media and fertilizer selection, organize crops into pH or EC groups, monitor nutrition regularly and ensure adequate levels of all nutrients are present in cuttings harvested from the stock. 1. Start with a quality growing medium. Some growers consistently produce excellent quality cuttings from stock plants grown in gravel, soil or locally produced compost to save costs. However, these locally produced substrates will often present the stock producer with challenges including inconsistent mixing, excess compaction or composting, limited root growth because of lack of aeration or excessive drying, and micronutrient toxicity (often manganese, depending on the rock type) when substrate pH decreases […]

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August 5, 2009

Scotts Introduces Four Controlled-Release Fertilizers

Scotts has added four new Osmocote Pro formulations to its controlled-release fertilizer portfolio. All four consist of 100 percent coated, homogeneous N-P-K prills blended with a top-quality, sulfated micronutrient package. The new formulations are: –Osmocote Pro 17-5-11 (three to four months)–Osmocote Pro 17-5-11 (five to six months) –Osmocote Pro 17-5-11 (eight to nine months) –Osmocote Pro 17-5-11 (12 to 14 months) Scotts says the coated, homogeneous N-P-K prills deliver a more consistent, steady and sustained release than growers would expect from a blended product containing uncoated nutrients. The formulations are available in a broad range of longevities, from three to 14 months, and the four offer the highest iron levels within Scotts’ Osmocote Pro portfolio. “These new formulations do not contain urea nitrogen, so it is possible to use them in covered operations as well as the more typical nursery, foliage and landscape applications,” says Chris Buchheit, marketing manager for Scotts Professional’s ornamental […]

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July 24, 2009

Understanding Plant Nutrition: Environmentally Induced Plants

Most nutrients are actively taken up by the plant from the soil solution. With active uptake, the plant roots use energy to scavenge the root environment for soluble nutrients. For nutrients that are taken up actively (like nitrogen or phosphorus), their concentration in the root medium (as measured with soil tests) tends to correlate well to uptake by the plant. The exceptions to this rule are calcium and boron. Calcium and boron are taken up passively by the plant. With passive uptake, nutrients only move into the plant along with the water used for transpiration. No transpiration, no uptake, regardless of the concentration of those nutrients in the soil solution. The environment where the plants are being grown will directly affect transpiration rates, and calcium and boron uptake. The types of environments that suppress transpiration can include: – Hot, humid conditions, especially when light levels have been reduced with excess […]

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June 4, 2009

Understanding Plant Nutrition: Low Media-EC

When growers talk about “lack of feed” or “hungry plants” (Figure 1), the issue is usually insufficient supply of fertilizer nutrients. The easiest way to measure fertilizer level in the root media is with an electrical conductivity, or “EC,” meter. What is Media-EC?       What Causes Low Media-EC? The initial concentration of nutrients in a container media is provided by the pre-plant nutrient charge, which may include lime (providing calcium and magnesium), and other fertilizers such as superphosphate, gypsum or urea-formaldehyde. Part of the initial nutrient source is immediately soluble and therefore affects the initial media-EC. Other nutrient sources are bound to the soil particles or are in a slow-release form (e.g. limestone, resin-coated fertilizers), and only affect EC as nutrients dissolve into the soil solution. Most media components, such as peat, bark or perlite supply a small amount of nutrients, whereas compost can supply significant nutrients as […]

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May 1, 2009

Smithsonian Gardens Fertilized With Dosatron

[imageviewer] Lela Kelly, vice president of Dosatron, was in Washington, D.C., last week visiting the Smithsonian Gardens near the White House. All the outdoor gardens and hanging baskets there are fertilized with Dosatron equipment on portable carts, she says.

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April 25, 2009

Understanding Plant Nutrition: High ph Problems

High media-pH (above 6.4) induced iron deficiency is the most common nutritional problem for certain iron-inefficient crops (Figure 1), including calibrachoa, diascia, nemesia, pansy, petunia, scaevola, snapdragon and vinca. Plants only take up dissolved nutrients through their roots. When the media-pH is too high, micronutrients (especially iron) are less soluble and unavailable for uptake by plant roots. High-pH induced iron deficiency can develop within one to two weeks, resulting in chlorosis of new growth and overall stunting. This problem is not occurring because plants need more “feed” or are “heavy feeders.” Instead, it occurs because the iron supplied in fertilizer becomes insoluble due to the high media pH. Getting Started We have undertaken considerable research and worked closely with growers to develop strategies to rescue crops that are stressed from high media-pH. If you think there is a problem, the first thing to do is test the pH and electroconductivity […]

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March 23, 2009

Understanding Plant Nutrition: Correcting Low Media pH

Iron/manganese toxicity is a common problem when media-pH drops below the ideal level in certain crops, including geraniums, marigolds, lisianthus, and pentas. As media-pH decreases (meaning the pH becomes more acidic), iron and manganese become more soluble, resulting in higher concentrations in the soil solution. For each drop in media-pH by one unit, for example from pH 6.0 to 5.0, solubility of inorganic iron in the growing medium (and availability of this iron for uptake by plants) increases by a factor of 1,000. Geraniums, marigolds and certain other species are very “iron-efficient” at taking up the soluble iron and manganese into their tissue. These species evolved to grow in calcareous (low-iron, high-pH) soils and “harvest” extra iron by exuding acid or chelating agents from their roots into the soil, growing extra root hairs and other processes. When we place those plants into an iron-rich greenhouse media and fertilizer regime, they […]

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February 26, 2009

IHA Adds Fertizilizer To Distribution Mix

Integrated Horticultural Alliance (IHA) and Florikan E.S.A. Corp have engaged in an agreement to provide BFG Supply, Inc., BWI Companies, Inc. and Griffin Greenhouse and Nursery Supplies with controlled release fertilizer blends featuring Florikote & Nutricote products. These products will be distributed by the above IHA members throughout their territories. Florikan E.S.A. Corp will manufacture Florikote and Nutricote blended fertilizer and provide vendor support to the IHA effective immediately. Florikan will also join IHA in their sales efforts with service and support from its sales team that is dedicated to the horticultural market.

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January 12, 2009

Feeding Frenzy

High Fertility Plant Products: Fertility Plus 19-2-19 is designed for today’s heavy feeders and most demanding plants. It’s engineered for more efficient nutrient uptake, and the triple chelation process makes nutrients more available requiring fewer inputs and less waste. This high-nitrate Fertility Plus has no urea, resulting in sturdier and stockier plants that are well-conditioned for store shelves. Organic Alternative Growth Products: Essential Plus 1-0-1 is a 100 percent natural organic product and OMRI certified for organically grown crops, herbs and plugs. Each of its ingredients has been selected to provide a rich source of organic building blocks not found in typical N-P-K fertilizers. This safe alternative to chemical hormones will help eliminate transplant shock and ensure seed germination and good rooting.   Fishy Feed Dramm: Made from fresh fish scraps that would generally fill landfills, Drammatic Organic Liquid Fish fertilizer is an all-natural substitute to chemical fertilizers. The fresh […]

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January 6, 2009

Understanding Plant Nutrition: The Series

Understanding Plant Nutrition: An Introduction Read about the basics on essential nutrients for plant growth, uptake of nutrients and pH’s effect on nutrient solubility. Nutrient Sources: Media Cation Exchange Capacity The authors take a look at the myth that cation exchange capacity is important to soilless media. Limestone and pH Why does limestone need to be added to soilless media? It’s all about pH management. Limestone, Calcium And Magnesium Limestone provides calcium and sometimes magnesium to container media. This article looks at the nutrient content of different types of limestone and how it influences calcium and magnesium levels. Irrigation Water Alkalinity & pH Water alkalinity and pH are two different measurements. This article explains the difference, how to interpret testing results and how to adjust management strategies accordingly. Irrigation Water As A Nutrient Source Water rarely contains enough primary macronutrients, but can be rich in secondary macronutrients. Check out this […]

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December 16, 2008

Constant Variables

Some growers were raised into it, and for some, their customers demand it from them. But for Lloyd Traven of Peace Tree Farm, going organic was more like an epiphany. Traven vividly remembers the moment that forced him to rethink his approach as a grower: After delivering herbs to a customer, Traven recalls standing around chatting with the buyer and watching what the customers were doing with the herbs. “The first thing they do is rub them and then sniff their hands. Second, they start picking the leaves off the plants and start chewing them.” This struck a nerve with Traven. “Every instinct I had was screaming at me to yell ‘No, don’t do that! This came out of my greenhouse. You don’t want to eat this.’” Think about what you ingest. Fertilizers are used in herbs, vegetables and edible ornamentals. They are something you can’t just wash off in […]

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