January 16, 2010

Understanding Plant Nutrition: The Complete Series

An Introduction Read about the basics on essential nutrients for plant growth, uptake of nutrients and pH’s effect on nutrient solubility.  Nutrient Sources 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 article for tips on making the most […]

Read More

January 4, 2010

Addressing pH Problems

If it was only as easy as turning a dial, pH problems would not exist. In the real world, the simplest way to avoid improper substrate pH is by keeping a close eye. Regularly monitoring substrate allows growers to identify when pH is just beginning to get out of range. In most cases, small pH adjustments (0.2 to 0.6 pH units) are easily accomplished by simply changing the type of fertilizer. Large pH adjustments can be time consuming, costly and typically result from infrequent pH monitoring.    The green line in Figure 1 (see page 44) represents a situation in which a grower is monitoring marigold substrate pH on a weekly basis. At week 4, the substrate pH has fallen out of the ideal pH zone and into the small corrective zone. The grower may have been using a fertilizer too acidic for the situation, and simply switching to a […]

Read More

December 28, 2009

Understanding Plant Nutrition: Geranium Nutrition

Seed and zonal geraniums are iron-efficient crops that are prone to iron/manganese toxicity when the media-pH gets too low. Once plants show toxicity symptoms of necrotic spots and marginal burn (Figure 1), the affected leaves do not completely heal. The only options become shipping lower-quality plants–to take additional time to produce healthy new growth that will cover the older damaged foliage–or throwing plants away.  Therefore, the best approach is to prevent iron/manganese toxicity (and low media-pH) from occurring. Here are some pointers for growing geraniums: Pointers – With normal fertilization practices, the acceptable pH range for iron-efficient crops like geraniums is 6.0 to 6.6.   – Pre-test your root medium to determine its acceptability for growing geraniums. Often, moistening the media to near container capacity and giving it three to seven days to incubate allows the limestone a chance to react and gives a more realistic starting pH measurement than […]

Read More

November 30, 2009

Understanding Plant Nutrition: Calibrachoa

Calibrachoa are often described as a “high feed” or “high iron” requiring crop. This is not exactly true. Calibrachoa are an iron-inefficient crop and are prone to iron deficiency because they lack the ability to take up iron from the soil solution if the media pH is too high. Once iron deficiency sets in, calibrachoa will often lose vigor and become susceptible to secondary problems like overwatering or root diseases. Therefore, to succeed with calibrachoa, you need to monitor media pH regularly and take the proper corrective actions when the media pH gets too high. Here are some pointers for growing calibrachoa. Points To Consider – With normal fertilization practices, the acceptable pH range for iron-inefficient crops like calibrachoa is 5.5 to 6.2. Once the media pH increases above 6.2, iron deficiency is likely (Figure 1).   – Make sure the iron deficiency symptoms are being caused by high media […]

Read More

October 20, 2009

New Product: Fertilizer Features Unique Combo

Ostara Nutrient Recovery Technologies began production earlier this month on a new slow-release fertilizer called Crystal Green, which is renewable, applicable to nurseries and combines nitrogen, phosphorus and magnesium. Jib Zablocki, Ostara vice president of nutrient operations, says Crystal Green is the only renewable fertilizer that can be used in the same manner as widely-used monoammonium phosphate or coated products, with the added benefit of high levels of slow-release magnesium. Zablocki adds that there’s no need to change equipment or application methods because Crystal Green can be substituted for any existing phosphorus source. “Its crystalline structure allows us to form a completely new chemistry for our industry,” Zablocki says. “Yet, unlike slow-release products, it is far more predictable as it is not affected by excessive moisture, bacteria and temperature changes. And its longevity is as reliable as coated products. “Your plants will see the difference, and the environment will thank […]

Read More

October 20, 2009

Scotts Adds Three Territory Managers

Scotts Professional recently announced the addition of three territory managers to its expanding network of field experts. The new hires are Shannon Ortigosa, Robbie Abillama and Sharon Gravitt-Warschauer. Scotts’ territory managers work with nursery and greenhouse growers throughout North America to develop nutrition and plant protection solutions that result in healthier, more attractive crops. Shannon Ortigosa Ortigosa is the new territory manager for Southeastern Florida. A former co-owner and operator of wholesale nursery Mario & Son, Inc. in Homestead, Fla., Ortigosa brings the perspective of a professional grower to her new position with Scotts. Her background includes purchasing, sales, employee management, event coordination and advertising. Ortigosa is bilingual and earned a bachelor’s degree in liberal studies from Florida International University’s School of Arts and Sciences.  Robbie Abillama Abillama has taken over territory manager duties for Scotts Professional’s newly created sales region of East, South and Central Texas. Abillama comes to […]

Read More

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 […]

Read More

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 […]

Read More

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 […]

Read More

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 […]

Read More

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.

Read More

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 […]

Read More
[gravityform id="35" title="false" description="false"]