The attraction of opposites: Using both soil and soilless production to enhance diversified vegetable and fruit operations - Part 2

The attraction of opposites: Using both soil and soilless production to enhance diversified vegetable and fruit operations - Part 2

Peach Hill Orchard, Martinsburg, PA-

On this mid-summer morning in central Pennsylvania, it turned out that tomatoes were not the first thing on Ammon Martin’s mind. While Ammon and his son Dave were certainly willing to discuss their greenhouse hydroponic tomato production with me, he explained with a smile that right now it was peach picking season. So, it was going to be the orchard that would consume much of their time over the next few days. This simple explanation very clearly illustrates both the opportunities and challenges that greet diversified direct marketers like the Martins, who have owned and operated Peach Hill Orchard, in Martinsburg, PA for over two decades.

Ammon started his production over twenty years ago with fruit trees and vegetables. To widen his season and therefore marketing window, he began growing tomatoes in high tunnels. However, the management and production in soil with unheated structures contained more yearly and seasonal variability than he desired. In order to have more control over his growing environment and therefore his crop productivity, he installed a CropKing hydroponic greenhouse about 20 years ago. Beefsteak tomatoes were their most important hydroponic crop, but European cucumbers were grown as well to add variety to the early spring produce selection. Along with hydroponic production, the Martin’s also produced bedding plants, vegetable transplants and hanging baskets in adjacent, but separate greenhouses. These protected environments were combined with both field vegetables and fruits for a wide diversity of crops to market.

For many years, they sold these varied crops through a small roadside stand at their dairy farm in addition to selling through the local flower and produce auctions. To enhance their direct-marketing ability and establish a year-round business, they built a permanent farm market about five years ago that was certainly well stocked with both produce and customers on the morning I visited. Various fruit crops and vegetables, along with meats and cheeses, provide consistent selection for all seasons. The hydroponic tomato crop, though, still played a key role in providing spring and early summer fresh produce to attract customers. However, as the summer season progressed each year, field vegetable crops, sweet corn, and the fruit trees consumed more and more time. To address the labor needs of their diverse operation, Ammon simply decided to end their hydroponic crop in late July of each year to focus on other farm responsibilities. The hydroponic tomatoes, along with a few cucumbers, are produced and sold in the months of March through July. Field vegetables, fruit, and cider then become the focus of Peach Hill Orchard.

Over time, the Martin’s found they were direct marketing essentially all of their produce and rarely needed to sell at the produce auction. In fact, they even discontinued growing bedding plants and hanging baskets because they found those markets were more crowded. Growing hydroponic and field vegetables and fruit for their market, it turned out, was a more profitable use of their time. This past year, they even added a small CropKing nutrient film system to grow hydroponic lettuce for their customers in the spring. Peach Hill Orchard, now run by Ammon along with his son Dave, demonstrates the potential of coordinating traditional fruit and vegetable production in soil with greenhouse hydroponic crops. This crop combination provides the Martin’s an opportunity to provide a diverse and high quality selection of produce to their customers throughout the seasons- and it certainly seems to be working!  

The attraction of opposites: Using both soil and soilless production to enhance diversified vegetable and fruit operations - Part 1

The attraction of opposites: Using both soil and soilless production to enhance diversified vegetable and fruit operations - Part 1

By Dr. Natalie Bumgarner

For horticultural crop producers, the balance between specialization and diversification on their farms must be continually managed. These days, the concept of diversification does not just apply to the types of vegetables planted in the field or varieties of trees in the orchard. Horticultural growers around the country have a wide variety of growing systems available to them to enhance the selection of crops they market and the seasons in which they are able to harvest and sell. Visiting with some of these experienced and diverse growers is really the best illustration of the potential of diversification. For me, a summer day spent traveling across central Pennsylvania certainly did reveal some intriguing paths to diversification.

Yarnick’s Farm and Market, Indiana, PA

As I followed the small, winding road through rolling Pennsylvania hills, there was no danger of missing Yarnick’s because all first-time visitors are guided by a road sign. As I approached the farm, greenhouses filled the valley and clearly illustrated diversification in action. Dan and Lynette Yarnick have been building and expanding the business for over 30 years, and their son Joey has also come on board to lead the farm into the next generation of diversification. The current farm market, which was certainly bustling, was built more than half a dozen years ago and is the direct-marketing portion of the Yarnick’s business. In the market, Lynette retails a variety of vegetables and fruits, along with their own Black Angus beef and many other food and gift items. In addition to supplying the farm market, Yarnick produce is marketed through SuperValu supply chains, Giant Eagles grocery stores and Eat ‘n Park restaurants.

It all started back in 1981 when Dan read a short article on hydroponic tomatoes in the Farm Journal. Although the farm was currently focused on dairy cattle and agronomic crops, Dan was intrigued by the possibilities of vegetable production that was not all tied to the season. From this first experience with tomatoes in a hydroponic greenhouse over 30 years ago, Yarnik’s farm has grown to about 300 acres in vegetable production. With this many acres under production, obviously the soil-grown portion of the crop has expanded. Yarnick’s field crops range from cabbage, leaf lettuce, candy onions, watermelon, cantaloupe, and zucchini to a large and well-known crop of sweet corn. Season extension practices, such as the use of row covers, enable Yarnick’s to expand the production season of their soil-grown vegetable crops. However, the hydroponic greenhouses have multiplied over the years as well and still play a very important role in the business. Currently, Dan is producing many varieties of hydroponic tomatoes- both modern and heirloom beefsteak and cherry varieties- along with peppers, cucumbers, eggplants, green beans, and even some giant radishes in spring.

Over the years, Dan has developed a hydroponic growing system that fits his needs as well as the palettes of his customers. He now grows in peat bags rather than the perlite or rockwool system that many hydroponic growers use because he prefers the way peat allows him to manage moisture and fruit quality. This hydroponic tomato crop is typically seeded in December to enable 10 months of production from March until November. Along with Dan’s tomatoes, Lynette also produces hydroponic lettuce and herbs in the living produce section of the market. Here, customers, who range from individuals to restaurant chefs can select and harvest their own fresh produce. A visit to Yarnick’s Farm Market demonstrates that diversity and freshness are much more than catch phrases at Yarnicks, and they look forward to continuing the fine tradition and the “Charm of Yarnick’s Farm”. 

Investigating iceberg lettuce in the hydroponic greenhouse – 2013 Trial, Part 1

Investigating iceberg lettuce in the hydroponic greenhouse – 

2013 Trial, Part 1
 By Natalie Bumgarner, Horticulturist
CropKing, Inc. Lodi OH

Why isn’t there hydroponic greenhouse iceberg lettuce?

Lettuce is the 2^nd most popular vegetable in the US (second only to potato), and head lettuce is certainly the most recognizable type. So, it is not uncommon for us to hear the question “Why don’t you produce iceberg lettuce in the greenhouse?”  There are, in fact, several key reasons iceberg lettuce is not commonly grown in vegetable greenhouses in the United States. They are listed below and loosely ranked by importance, but these reasons may vary depending on production area and market. 

 

1)  Market potential and price

One of the most important reasons that we do not see head lettuce in the greenhouse is because the economics of the market are not always encouraging. Nearly all of US head lettuce is produced in California (spring through fall) and Arizona (winter). Huge expanses of open field production are dedicated to lettuce production in some of the most productive cropping areas in the world. Soil and climate factors make these regions quite appropriate for head lettuce production and the scale of production also contributes to competitive advantages. For example, recent terminal market data reported that head lettuce cartons (approximately two dozen 2 lb. heads of lettuce) are selling for $11.00 to $17.00. These prices illustrate that greenhouse producers are unlikely and unwilling to produce head lettuce at prices that could be competitive with field production.  An additional facet to this topic of markets is that recent per capita consumption of head lettuce has been flat or on the slight decline as other leafy vegetables have become more popular.

Iceberg lettuce typical in California open field  production. Specific cultivars are slotted in specific times of year for production regions of CA and AZ across the entire year.

 2) Production time

Typically in the open field, head lettuce matures in 70 to 80 days in the summer and up to 130 days in winter or lower light and temperature seasons. Of course one of the benefits of greenhouse production is the potential for faster growth rates and reduced production times. To date, in summer greenhouse production in OH, we have harvested our iceberg lettuce approximately 55 to 60 days after seeding. However, the total weight of our lettuce may not equal field packed cartons. This production time contrasts with a bibb production schedule in the greenhouse which might produce a crop in 40 to 50 days. 

3) Nutrition

As consumers become conscious of the nutrient and antioxidant levels in their food, they continue to become more discerning in food purchases. Due to underlying genetics, plant growth form and a few other factors, iceberg lettuce is not the most nutrient dense leafy green vegetable. The table below (From USDA National Nutrient Database for Standard Reference Release 24 ) gives average nutrient information for the most common types of lettuce. Remember that these are averages from primarily soil grown crops from around the country, so they do not represent the exact profile of product from individual greenhouses or cultivars. Nevertheless, this table does support the generally held perception that iceberg lettuce contains fewer nutrients per serving that other lettuces and certainly other leafy greens. However, keep in mind that iceberg lettuce from greenhouses has been less often evaluated than that from the open field.   

4)    Customer Preference and Perception

This potential reason for the lack of iceberg lettuce in US greenhouses is linked with the nutrition topic discussed above. Most greenhouse lettuce producers are growing and marketing their crop as a premium product. This means that the quality of the crop is crucial, but the perception of the crop is also important. Iceberg lettuce is often viewed by many discerning consumers as inferior in taste, visual appeal, and nutrition to the bibb, romaine and leaf lettuces. There is also little attraction based on novelty or distinctiveness. These views mean that many of the most profitable potential customers for hydroponic greenhouse producers may be less interested in iceberg than other leafy crops. However, if greenhouse producers were able to market a product with comparable attributes (crisp, multiple servings per head, etc) and improved taste, freshness, or nutrition, these perceptions and preferences could change.

5)    Adaptability of cultivars and environments 

Much of greenhouse lettuce production (especially bibb) utilizes cultivars that were specifically bred and developed for greenhouse environments. These cultivars can generally be depended upon to perform consistently across seasons and even geographic areas. When investigating types of lettuce, like iceberg, that are less often produced in greenhouses, preferable cultivars and knowledge of how they may perform is limited.

Additionally, iceberg lettuce often requires specific environmental conditions to produce the tight head consumers are accustomed to- without bolting or becoming bitter. So, even though we can control temperatures closely in greenhouses, producers may not be able to exactly emulate conditions that are common in field iceberg production. There may be more seasonal constraints of light and temperature on iceberg production in many US greenhouses than we experience in producing other types of lettuce.   

So, why would we be interested?

After spending the time to try and elucidate why iceberg is rarely produced in hydroponic greenhouses, you are probably asking what would possibly be the attraction. While I will be the first to admit that greenhouse iceberg is unlikely to become a US market force in the near future, there are some reasons for investigation.

First, familiarity is not always a negative. Some consumers will always be attracted to what they know best and producers should always be ready to fill small market niches if they are possible and profitable- especially if they can provide a product with superior quality. 

Secondly, we at CropKing deal with producers not only in the US, but also internationally. Market demands and dynamics may differ considerably in these areas. For instance, in the Caribbean islands where imports are expensive and often of poor quality, iceberg may be both desired by consumers and potentially profitable for greenhouse growers.

 Thirdly, it is always important to investigate potential crops and understand both the benefits and drawbacks to their cultivation to assist current and future producers- essentially, we need to have solid backing to the answers that we give growers.

Goals and Early Observations

Main Objectives

•      Produce 5 iceberg cultivars in spring and summer greenhouse environments in OH

•      Evaluate yield as well as broad metrics of internal and external quality

•      Evaluate production timing and suitability for the CropKing NFT system

After one run, we observed

•      Head lettuce production was possible

•      Head weight and density may not be the same as field iceberg

•      Not all cultivars appeared to be well suited to our conditions because some bolting and tipburn occurred

•      Anecdotally, the taste of the produce was encouraging 

Additional Sources

•http://anrcatalog.ucdavis.edu/pdf/7215.pdf
•http://151.121.3.194/cat/?shortcut=terminalMarket
•http://www.agmrc.org/commodities__products/vegetables/lettuce-profile/

Late Fall to Spring Leaf Lettuce Trial

Late Fall to Spring Leaf Lettuce Trial

Results from four separate trial runs of nine leaf cultivars 

in NFT production systems

Dr. Natalie Bumgarner

Objectives

Hydroponic lettuce production in the United States now encompasses a wide spectrum of lettuce types and cultivars. While Bibb cultivars still occupy a large percentage of the market, many growers are also seeking attractive and distinctive lettuce cultivars to meet consumer demand. Due to these factors, leafy cultivars, including looseleaf and Lollo types, are becoming more common in hydroponic greenhouses. However, some of these cultivars have been more often grown in soil based systems, and there is a need to better understand their performance in the greenhouse. Consistency in both productivity and timing is important for greenhouse growers, and seasonal conditions can have a large impact on cultivar performance. Trialing of available cultivars under differing conditions is important in informing grower decisions. Important points of evaluation are growth rate, yield and visual coloration. The goal of this set of trials was to evaluate a selection of leaf lettuce cultivars through a range of late fall, winter, and early spring conditions to evaluate their potential for greenhouse growers in the Midwest and northeast. Cultivars were obtained from varied seed suppliers to represent a broad selection of cultivars available to lettuce producers. 

Methods and Management

Primed and pelleted seeds were seeded by hand in pre-moistened 1” x 1” x 1 ½” rockwool cubes. Seeds were germinated in clear water in seeding trays in the nursery. Nutrient solution was added in the nursery 7 days after seeding and lighting was used for the seedling phase (T5 florescent fixture) and seedlings were grown in flowing nutrient solution in the nursery for approximately two weeks before transplanting. After transplanting, lettuce plants were grown out in the channel for five weeks prior to harvest. The nutrient solution was continually cycled through the CropKing Fertroller where automatic pH and EC adjustments met programmed solution set points. The pH was maintained at 5.8 by the addition of dilute sulfuric acid. EC was maintained at 1.8 by the addition of concentrated fertilizer solution and source water.

* It is important to note that these trials were carried out over set periods of time and harvests were made regardless of plant readiness for sale. Clear comparisons were the main goal, and this resulted in low weights for some cultivars. Also, no supplemental lighting was used after transplanting even under these low light northern conditions. In a commercial operation, more time would have been give these heads to reach a saleable size or lighting would have been added to increase growth rate and crop quality.  

Some Concluding Thoughts

There are always many interesting observations from cultivar trials carried out across different seasons.  From these trials, I would like to make a couple observations in addition to the common trends of 1) decreased growth under lower light/winter conditions, and 2) more dense, compact, and more deeply pigmented lettuce grown under higher light levels.

The first important take-away from these cultivar trials is the importance of understanding your customers and market demands when selecting a lettuce cultivar. While it is a generally true statement that different lettuce cultivars grow at different rates, these differences can be clearly seen in this selection of leaf lettuces. For example, the Tropicana cultivar is a typical green leaf crop sold for soil production that can also be grown in the greenhouse. As can be seen in the images and yield numbers, this green leaf lettuce has a more rapid growth rate than the Lollo Biondo (blond, such as Livigna and Lozano) or Lollo Rossa (red, such as Carmesi and Orville)

cultivars in the evaluation. The Lollo lettuces were bred and developed for specialty

markets and have attributes such as color and texture that are not present in some of the other common leaf cultivars. On a per-plant basis; however, they may not produce a similar sized crop in a similar time period. Conversely, the smaller size of some of the Lollo cultivars may make them more appropriate for a leaf mix where their growth will not be too rapid for other varieties in the mix. These are just some of the factors that are important for growers to keep in mind as they select cultivars.

The second thought worth mentioning is best explained using pictures. These two images illustrate some of the impact of crop management on yield and production. The image on the left shows transplants at an appropriate size for transplanting (run 1) while the image on the left shows plants that are larger than optimum (run 4). In our greenhouse we typically transplant when the plants are similar to the size on the left. However, as sometimes happens, schedules and other jobs encroach on our work and we transplant a few days after optimum. Older transplants can be more stressed and take a little longer to transition to growth in the channel. This increased plant stress could be a key cause of the similar or lower weights observed in run 4 as compared to run 3 even when light levels were higher in run 4. So, proper cultivar selection should be paired with timely and appropriate management to obtain the best crop. 

Late Summer to Winter Bibb Lettuce Trial

Late Summer to Winter Bibb Lettuce Trial

Results from four separate trial runs of twelve Bibb cultivars 

in NFT production in Ohio

By Dr. Natalie Bumgarner

Introduction

Hydroponic lettuce production in the United States now encompasses a wide spectrum of lettuce types and cultivars. Although there is an increasing amount of diversity in the cultivars being produced in hydroponic greenhouses, Bibb cultivars still occupy a large percentage of the market. They are also often the first crop produced by many beginning growers around the country.  While some growers tailor their cultivar selection to seasonal conditions, many growers at a variety of scales produce a single cultivar for the whole year that is adapted to a range of conditions. Both of these production patterns, though, require the growers to be familiar with the growth habits, characteristics, and productivity of the cultivars. This trial was designed to evaluate a selection of Bibb lettuce cultivars through a range of late fall and winter conditions to evaluate their potential for greenhouse growers in the Midwest and northeast. Cultivars were obtained from a variety of seed suppliers to represent a broad selection of cultivars available to lettuce producers. 

Methods and Management

Primed and pelleted seeds were seeded by hand in pre-moistened 1” x 1” x 1 ½” rockwool cubes. Seeds were germinated in clear water in seeding trays in the nursery. Nutrient solution was added in the nursery 7 days after seeding. Seedlings were produced in flowing nutrient solution in the nursery for an additional week to two weeks before transplanting. After transplanting, lettuce plants were grown out in the channel for four to five weeks prior to harvest. The first two runs were carried out on the typical summer schedule (2+4 weeks) while the third and fourth were carried out in a more winter schedule of (3+5 weeks). The nutrient solution was continually cycled through the CropKing Fertroller where automatic pH and EC adjustments met programmed solution set points. The pH was maintained at 5.8 by the addition of dilute sulfuric acid. EC was maintained at 1.8 by the addition of concentrated fertilizer solution and source water.

* It is important to note that these trials were carried out over set periods of time and harvests were made regardless of plant readiness for sale. Clear comparisons were the main goal, and this resulted in low weights for some cultivars. Also, no supplemental lighting was used after transplanting even under these low light northern conditions. In a commercial operation, more time would have been give these heads to reach a saleable size or lighting would have been added to increase growth rate and crop quality. 

Concluding Thoughts

As I look over these interesting numbers from four consecutive runs of this Bibb lettuce trial, there are a couple thoughts that jump to the top of my ‘important take-home points’ list.

The first and likely most glaring message is that light, not surprisingly, is pretty important for lettuce growth and quality. As can be seen by the average solar radiation and weights in the previous tables, low winter light in northern climates can be a significant hurdle. It is clear that lengthening production cycles by two weeks in the winter didn’t produce similar sized heads to the late summer/early fall run. The fourth run had just a little more than 33% of the average solar radiation present in the first run (In future blog posts, we will break these numbers down to daily integrals). Average temperatures in the first two runs were a little higher as well (due partly to solar gain). However, the individual contributions of light and temperature are difficult to clearly separate.

The pictures that follow drive home the point that light/temperature relationships are crucial for lettuce growth and development. Supplemental lighting would have changed this equation substantially, but that is another broad topic altogether.  Also, additional time in the channels would have made many of the smaller Bibb heads quite marketable. Production timing and seasonal factors should not be overlooked if your goal is to produce consistently sized heads throughout the year in northern climates. 

  

The second important theme that is apparent in these yield numbers and the pictures that follow is the need to understand the variability in cultivar performance. While all the cultivars trialed here were bibb or butterhead lettuce, not all were bred for hydroponic or greenhouse production. In controlled environment production, consistency is key. Consistency is important not only within a harvest period, but also through the seasons. The second yield table shown above illustrates this point. The deviations across the 4 runs as well as the % weight loss from the highest yielding run (1) and the lowest yielding run (4). It is clear both in these variable yields and in the photos below that in our location without supplemental lighting, some of these cultivars are not suitable for year-round production. The larger framed lettuces tended to be the most variable across runs and were visually the least appealing under winter light conditions while many of the bibbs bred for greenhouse production were more consistent in weight and visual quality across the trials. These trends held true in both the green and the red cultivars.

Knowing your cultivars is crucial in creating an appealing and consistent product throughout the year!