You are here


Plant Nutrients - The Mighty Macros

Posted by Jake Emling, CropKing Horticulturist on 11/6/2018

For the second part in this this three-part series we will be discussing the major elements that are typically used in large quantities – calcium, magnesium and sulfur. Some people consider these macro elements and will usually put nitrogen, potassium, and phosphorus also in this category.


Part 2: Rapid Relative Humidity Decreases in the Greenhouse

Posted by Jim Brown, Horticulturist on 10/22/2018

Previously on the blog we talked about rapid relative humidity increases and how plant tissue is affected. Today, we’re talking about part 2 – rapid relative humidity decreases. If you missed part one, check it out here!

Bumbling in the Greenhouse – All about the B’s

Posted by Jake Emling, CropKing Horticulturist on 9/4/2018

From the title you probably can guess what this week’s post is about. It is not about how I move around the greenhouse this time of year but rather my small employees that help with pollination. It’s all about the bee’s this week. After some work in the greenhouse the last couple of days I figured to share some insight on the little “helpers” that occupy the greenhouse even when I’m not there.

Part 1: Rapid Relative Humidity Increases in the Greenhouse

Posted by Cropking on 5/24/2018

When the relative humidity in the greenhouse environment either increases or decreases rapidly, the adaptation capabilities of the plants growing in the greenhouse environment may be challenged beyond the breaking point.

It’s the rate of change in the relative humidity rather than just the difference between the old relative humidity and the new relative humidity levels that can challenge the plant’s ability to adapt without resorting to sacrificing some of its tissue.

Nutrient Solution Management in Recirculating Systems

Posted by Cropking on 11/7/2014
Hydroponic Bibb Lettuce

In recirculating hydroponic systems producing leafy crops, one of the main factors in the control of the grower is the frequency of tank changes (ie pumping out and turning over the recirculating solution). Since we generally manage the solution based on EC, we are assessing the total amount of solutes in the water. We don’t know the balance of each nutrient individually, so tank changes are carried out to try and maintain necessary levels of nutrients. Essentially, our goal is to change the nutrient solution often enough that we don’t have detrimental buildups of unused ions or depletions of important nutrients. Also keep in mind that different water sources have different background ion levels that can slow or speed up imbalances in the nutrient solution.
This tank change practice is really based on cost efficiency. There are nutrient solution management systems that have the ability to manage based on individual ions, but these are much higher cost than the typical systems installed in small to mid scale greenhouses. This hydroponics system cost savings comes at the price of more frequent tank changes that maintain a safe margin of nutrients in solution.

Cucumber Production- An Overview of OH numbers in 2013 and 2014

Posted by Cropking on 10/21/2014

Overview and Data Considerations

This data covers a couple of years of data (2013, 2014). So, the goal is to present to you an overview of crop yields and schedules.
Several of the main cultivars that we carry and that our customers use were trialed. However, these data do not represent all cultivars at all times of year, so comparisons across years are limited,
One of the most important things to keep in mind is that these trials were carried out in relatively small blocks imitating hydroponics at home. Our vine crop greenhouse is mostly dedicated to tomato production, so cucumber trials took place in units of 10-20 buckets on the western side of the greenhouse.
In some respects, these small sections of space dedicated to hydroponic cucumber production are similar to many grower houses, but it is important to remember that yields can vary according to light in different locations within the greenhouse. These trials were all carried out in Lodi, OH, so we cannot account for location variation that may be seen in other areas or seasons.
All of these trials were run with the plant maintained in an umbrella system. The majority of the crops were produced without pinching and were removed when the main leader reached the floor after traveling up to the wire and back down.

Summer 2014 Oakleaf Trial

Posted by Cropking on 9/12/2014

Seeding was done by hand into pre-moistened 1” x 1” x 1 ½” cubes of three different media (Grodan 200 ct rockwool, Oasis XL 162, and GrowTech 162). Seeds were germinated in clear water in seeding trays, and were transferred to the nursery and nutrient solution 3 to 5 days after seeding. Seedlings were produced in flowing nutrient solution in the nursery for an additional 10 to 12 days before transplanting. Due to the season, no supplemental lighting was provided during the seedling phase. After transplanting, plants were grown out in the channels for 25 to 28 days until harvest. The nutrient solution was continually cycled through the 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 1.7 by the addition of concentrated fertilizer solution and source water. Tank changes were carried out every two weeks.

Branching out with Brassicas - Summer trial in NFT production in Ohio

Posted by Cropking on 8/4/2014

In the greenhouses that I visit and crops I discuss with growers, it is clear that lettuce still fills a majority of plant spaces in the NFT system. However, we field an increasing number of questions about the many other leafy crop possibilities. Many of the other leafy options are in the Brassica family - cabbage cousins, essentially. These include kale, mustard, mizuna, and pac choi most commonly.

2014 Tomato Trials- Summer Sneak Peak

Posted by Cropking on 6/12/2014
Hydroponic Tomatoes

For many of the producers that we serve, beefsteak tomatoes are a large majority of their production. However, trends in consumption and competition are increasing interest in specialty cultivars. From demand for farm to school salad bar items to farmers market mixed baskets, there are a range of options for small fruited and colored tomatoes. While visual interest and taste are critical in these cultivars, it is essential that production be adequate and relatively consistent over the season. These two questions are the reason behind this trial. Exhaustive yield data is not possible on the scale that we trial in our test greenhouse, but early evaluation is essential to begin to make suggestions for growers. So, this evaluation was carried out on small plots of fifteen cultivars to assess plant production throughout the season. These are preliminary trials to determine what cultivars to trial more extensively in the future.

Dealing with a Rexless Summer?

Posted by Cropking on 5/12/2014
Hydroponic Bibb Lettuce

For growers, there exists something of a codependent relationship between them and their cultivar of choice. Due to uncertainties in seed production and demand, there is always the possibility of seed shortages or movement by the industry away from the ‘old faithfuls’. For bibb growers, the popular cultivar Rex is likely going to be less available this summer and early fall and so the questions of what other options to grow certainly are coming to our attention. While it is never possible to guarantee other cultivars will seamlessly replace current ones, CropKing’s trialing and research program is carried out to assist decision making in these areas. So, the best way for me to help growers decide what to grow is to show you what I have observed and measured in our greenhouses here in Lodi.


Get News, Updates & Special Promotions  

sign up now