Thursday, July 25, 2013

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”. 

Wednesday, July 3, 2013

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 2nd 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