If you think automation is solely for large nurseries, think again. Find out how a small Canadian nursery invested in mechanization and technology to improve production.
We caught up with Todd Baker, owner of Baker’s Nursery in Bayfield, Ontario, Canada, to find out which parts of his nursery are automated. Baker’s Nursery grows young plants for growers in eastern North America. Plants are propagated by cuttings and divisions, as well as tissue culture. Baker and his team grow tree liners in containers; grass plugs and perennials in plugs up to quarts; and woody cuttings in plugs and quarts. Field production for grass and perennials totals 15 acres along with half an acre of greenhouse space and a quarter of an acres of outdoor production space. The nursery is active about 10 months a year with a staff of four to 10 people, depending on the time of year.
Nursery Management: At what point did you realize automation was needed? Was it due to a labor shortage or an efficiency problem?
Todd Baker: It had more to do with the fact that we are very hands-on in our business and prefer to work smart vs. hard. We have been fortunate to have always had a reliable local labor pool. In the past, we had 30 staff at peak. Now we are usually less than 10. And looking at systems has been a sideline hobby for years. I have always sought ‘flow’ in the work processes.
NM: What did you finally decide to implement?
TB: The investments we have made are designed to eliminate pinch points or quality traps. The vacuum trimmer, which we began using three years ago, allows us to quickly process many plants with almost perfect consistency. Last season we installed a pot/flat-filling machine. This year’s investment has been in RFID cloud-based inventory and sales management.
NM: What type of capital investment did it entail? What advice would you give growers trying to decide on how it pays off for them?
TB: Our nursery is a small, boutique young-plant operation. The annual investment is usually $20,000 to $40,000. Payback? Well, it starts with ‘Will this improve the quality of life of me and my staff?’ Less bending, lifting etc. Every business has jobs nobody wants to do. I don’t want to do them, either. Payoff can be measured two ways: costing you less for the same task finished or, my preference, more money coming in from the same task/investment/space etc. Don’t forget about being able to take advantage of timing. If the perfect window for an operation is one day long and you take a week, you are diminishing the potential value of your crop.
NM: How has automation changed production?
TB: Each piece has its own story related to changed production, but the common denominator is that they make the work faster and easier. Happy people do better work.
NM: What are the pros and cons?
TB: Pro: machinery allows repeatable consistency. You can develop written protocols for the tasks which eliminates uncertainty. Cons: Sometimes the noise interferes with pleasant conversation. Setup time can be variable depending on how familiar staff are with the changeovers .
NM: What is your expected return on investment (ROI) of these investments?
TB: The trimmer was a $20,000 acquisition cost. We compared how long it took to hand-trim 1,000 quarts vs. the trimmer. We found it saved $10 per 1,000 plants compared to the manual version we had set up, including trimming by an experienced staff person and cleanup of trimmings from the walkways. With the trimmer we pick up the plants, trim and set down. The $10 per 1,000 didn’t include the extra jobs completed. We removed any culls or dead plants. Now we’re able to set down full trays and have a more accurate inventory count. The space recovery, inventory accuracy and simplicity are worth more than the savings. Not to mention the skill requirement is lower and the output is 100% consistent. So, if I estimate the savings of $10 per 1,000 plus another $15 for the consolidation/inventory accuracy, the trimmer is paid after 800,000 plants have been trimmed. Our woody plants get trimmed twice, and now that we have it, we also trim our 72 trays out of propagation as well.
Todd Baker is the owner of Baker’s Nursery in Bayfield, Ontario, Canada, along with his wife Susan. The young plant nursery, which includes a tissue culture lab, ships product across eastern North America.
Reliable roses
Features - Rose trials
The American Rose Trials for Sustainability provides regional trials to help answer the question, ‘Can we grow that here?’
The American Rose Trials for Sustainability (A.R.T.S.) is here to help the industry and consumers identify the strongest performing roses for their region through our independent scientific trials held at botanical gardens, parks systems and universities. How often have you seen a national ad for a beautiful new rose and asked yourself, “Can we grow that here?” Questions naturally progress to: Will this plant be cold hardy; Does it demand too much water for our arid climate; Can it take our intense summer heat; or Can it take our wet springs? Growers recognize and appreciate that not all plants grow well in all places. The challenge with a nationally loved and distributed plant like the rose is finding varieties that do well in your region. It’s important to find a trustworthy and independent voice that has grown those cultivars in your region to help guide you.
The A.R.T.S. team is made up of scientists, public horticulturists, nursery growers and extension professionals. Our goal is to identify which roses are the most pest resistant, drought tolerant, low maintenance, vigorous and beautiful for each unique U.S. climate region through our regional tests, which are done with high scientific standards. We grow the roses under low input conditions without pesticides and evaluate them monthly during two growing seasons. They are rewarded for parameters related to their health, flower power and plant form. Test roses must perform equal or better than the industry standards planted with them to earn an A.R.T.S. Local Artist award and be recommended for a particular region.
Instead of using the USDA Hardiness Zone Map to delineate regions, we use the Köppen climate system as it accounts for both temperature and precipitation levels and the timing of each. This system has been the go-to resource for ecologists studying communities of plants and the overall ecosystem. The USDA cold hardiness zones, although helpful, only take into account the lowest minimum winter temperature. The Köppen climate system is a more comprehensive tool to help us better answer the question, “Can we grow that rose here?”
In this industry, we know better than anyone that temperature and precipitation directly impact not only plant growth, but also disease and insect pressure.
In deciding which new roses to offer your customers, we encourage you to try some of your regional 2021 and previous year A.R.T.S. Local Artist winners. With our years of data on these roses growing in your region, we can help you confidently answer the question, “Can we grow that here?” We are proud to serve you as an independent and trusted voice sharing which roses have passed our tests as you navigate through the roses that will not only look good in retail, but be successful for your customers and keep them coming back to you as their trusted source.
To find out more about the A.R.T.S. program and all the winners for your region, please visit www.trustedroses.com
Bay Cottage (‘POULcot003’) Massive clusters of tiny, clear-pink, single blooms cover this low and spreading shrub rose. The petal bases are white and nicely frame the golden stamens. Foliage is glossy and stems have red highlights in the sun. Introduced by Poulsen Roser AS.
Brindabella Purple Prince (‘GRAppl’) Large, double, high centered, purple blooms emit a rich citrus-like scent. This floribunda has a dense mounded plant habit. Introduced by Dig Plant Company.
Cherry Frost (‘OVEredclimb’) Small to medium sized cherry-red blooms are borne in abundant clusters throughout the season. Flowers are long lasting and keep their clear bright color from beginning to end. It can be grown as a compact climber or large freestanding shrub. Introduced by Star Roses and Plants.
Coral Knock Out (‘RADral’) Clusters of warm peachy-orange blooms are borne abundantly throughout the season on this full and mounded shrub rose. The vibrant flower color is offset well by foliage that starts out red and matures to a rich green. Introduced by Star Roses and Plants.
Canyon Road (‘MEIscarlebo’) Double brick-red flowers are borne in loose clusters and framed by dark glossy foliage. This floribunda is compact growing a bit wider than tall. Introduced by Star Roses and Plants.
Easy Elegance Chi (‘BAIllim’) Abundant small burgundy-red double blooms cover this densely growing shrub rose. The dark green and semi-glossy foliage makes a great backdrop to the flowers. Introduced by Bailey Nurseries.
Elaine Paige HT Poulsen (‘POUlht008’) The large peachy-pink double flowers of this fragrant hybrid tea are borne singly and in small clusters. Plants are vigorous and compact. Introduced by Poulsen Roser AS.
First Editions Campfire (‘CA29’) This shrub rose has bright, multitoned blooms that start out yellow and transition to cream and carmine. Blooms are borne in small clusters on spreading plants that are wider than they are tall with semi-glossy foliage. Introduced by Bailey Nurseries.
Flower Carpet Pink Supreme (‘NOA168098F’) Massive clusters of double hot-pink blooms are produced on vigorous, spreading plants. This shrub rose has glossy foliage and is well suited to humid climates. Introduced by Anthony Tesselaar Plants.
Oso Easy Double Pink (‘MEIriftday’) Clusters of double, medium-pink blooms cover this low growing shrub rose throughout the season. It grows wider than tall and makes a great front of the border ground cover. Introduced by Spring Meadow Nursery.
Top Gun (‘WEKmoridahor’) Semi-double blooms begin red and transition to pinker tones as they age. The petals frame the bright golden stamens well. The medium-sized blooms are borne in clusters on this well-branched shrub rose. Introduced by Weeks Roses.
True Bloom True Grace Blush-pink double blooms are contrasted well by the dark attractive foliage. The large high-centered blooms are born by sturdy stems on a medium sized shrub. Introduced by Altman Plants.
True Bloom True Romance Very full warm-pink blooms are complimented by the vibrant green foliage of this vigorous shrub rose. Introduced by Altman Plants.
True Bloom True Sensation Bright shades of orange and pink blend together in the double blooms of this upright hybrid tea. The unique blend of color makes this a great plant to place where it can be enjoyed up close. Introduced by Altman Plants.
White Knock Out (‘RADwhite’) Nearly yellow buds open to crisp and clean single white blooms with attractive yellow stamens. The dark blue-green foliage contrasts nicely with the abundant blooms on this low growing shrub rose. Introduced by Star Roses and Plants.
Sailing through the storm
Features - Cover Story
Growers from across the country analyze the foggy state of the industry.
The novel coronavirus, ensuing uncertainty, quarantines and stay-at-home orders have created a challenging environment for nurseries.
Wholesale nurseries have had to determine whether they are allowed to stay open in the wake of COVID-19. Nurseries that ship cross-country have had to track whether their customers are open, as well. Landscape contractors and retail garden centers in some states have had to fight for “essential” status, a struggle that continues at press time. Keep an eye on our website (nurserymag.com) for the latest updates.
Many nurseries have taken the next step to determine how to abide by the guidelines set forth by the Center for Disease Control. Giving up on spring isn’t an option.
By and large, our nation’s wholesale nurseries are still shipping trees and shrubs even while social distancing. They have constantly evolved their workflow and best practices as guidance from federal, state and local authorities is updated, and in some cases, reinvented their business on the fly. As such, any operational changes or new protocols mentioned in this article are accurate at press time in late April. Depending on when you read this article, they may no longer be in place.
Alan Jones, owner of Manor View Farm in Monkton, Maryland, says his business has stayed open with some changes.
The 100-acre nursery grows a wide range of finished B&B trees and shrubs and propagates a wide selection of potted shrub liners for sale to growers. Jones says the nursery has slightly reduced its office hours by one hour a day. Delivery from its landscape distribution center to job sites is still very heavy, he says, though walk-in traffic has slowed.
“Landscapers in Maryland are considered essential and most are still working,” Jones says. “A few companies have closed voluntarily out of concern for their crew’s health.”
Christa Orum-Keller, chairman and president of Midwest Groundcovers, says her wholesale business is fully operational and ready to serve its customers.
Midwest Groundcovers, based in St. Charles, Illinois, produces more than 20 million plants in one of the broadest collections of species and plant groups of any nursery in the U.S., over 655 acres of production facilities.
Dealing with constantly changing state regulations kept Christopher Uhland, owner of Harmony Hill Nursery in Downingtown, Pennsylvania on his toes. While nurseries and greenhouses were deemed essential and permitted to stay open, in mid-April the governor ordered all independent retail garden centers to close. They were not allowed to have no-contact sales through curbside pickup or delivery, which was a compromise in several other states. When the pandemic started, Uhland had a contingency plan. As it progressed in the beginning, he planned to dig his normal supply of orders, plus a few extras to have on hand when the situation broke. Instead, he had to proceed with extreme caution and dig only on speculation. With landscape customers cancelling or postponing orders because they aren’t permitted to do commercial installations in some cases, he’s finishing up orders, wrapping up his fertilization program and getting into shut down/summer maintenance mode early.
Ariel Montanez, general manager of Pender Nursery in Garner, North Carolina, says the pandemic has yet to slow down production at the nursery, but they have experienced a 5-10% decline in sales compared with this time last year. While that is a workable situation, Montanez says with the ideal weather the area was experiencing before the nation started sheltering in place, he thought the nursery, which sells to landscape contractors, rewholesalers and retail garden centers, could have “easily seen a 25% increase in sales over last year.”
North Creek Nurseries, a wholesale propagation nursery in Landenberg, Pennsylvania, has also experienced about a 5% decrease in sales. Steve Castorani, North Creek's president, says the shifting regulations and closures have affected his customers.
"We anticipate demand when things open up, so we are still producing new product," he says.
Lorne Blackman, owner of Walla Walla Nursery experienced a roller coaster effect in his home state of Washington.
“We were doing OK at first, until our customers started closing,” Blackman says. “A lot of cancellations came in during the first two weeks of April. But at the last minute, business rebounded, and we came in about 80% of last year.”
He expected late April to be a “blowout” in sales for the 40-acre nursery that sells primarily to rewholesalers and independent garden centers. The nursery, which employs 170 people, was awarded funds through the Small Business Administration’s Paycheck Protection Program (see page 14 for more details on relief packages).
John Lewis, owner of JLPN Liners in Salem, Oregon, had shipped out nearly all of his liner material before the virus put a stranglehold on the country. His only cancellations, which represented less than 1% of his sales, were from nurseries in Eastern Canada that couldn’t get their labor from South America.
Extremely wet weather, not COVID-19, caused a dip in sales in April at Wolfe Nursery Direct’s Fort Worth, Texas, rewholesale location. Manager Stacy Estep says although many of her landscape customers jobs cancelled or postponed, they’ve made up for it in new business and many are booked up a month to six weeks in advance. But her customers who do new installations are worried about the future of the housing market, which will also impact her business, she explains.
Loma Vista Nursery in Ottowa, Kansas, is now applying lessons learned from the 2008 economic downturn, says president Lyndsi Oestmann. The nursery “invested thoughtfully in safety and security for our team and in the financial health of the company,” she says.
“As a company, we’re here to help. We’re here be part of the process of ensuring that this industry is as it’s always been: essential,” she says. “Through trusting in what we know, what we’ve experienced and where we’ve been — our industry can apply the best of its key learnings to a future we may not be able to control, but that we can step into with confidence in who we are as professionals and in the valuable services we provide.”
New precautions
Orum-Keller has implemented some changes to Midwest’s protocols in line with the CDC’s precautions. This includes moving as many primarily office and sales employees as possible to working remotely and shifting in-person meetings to video meetings. Midwest has also separated its production work teams, so they are not mixing — in break rooms, bathrooms, etc. By cutting back on intermingling and fraternization in somewhat close quarters, that change aims to reduce or limit the possibility of infection in on-site work forces. Midwest has also been encouraging customers to use the company’s online resources including an increased emphasis on online ordering. Shipping is taking place in the normal fashion, but Midwest has set up hand washing stations on its delivery trucks. The company also is eliminating the need for papers to be signed, which is another way to reduce the spread of the virus through limited contact of commonly touched objects. Orum-Keller also is preparing for an influx of delivery jobs.
“We expect a possibility that when things open up, there will be more requests than usual for delivery of orders,” she says.
The crew at JLPN created four- or five-person squads instead of the normal 15-person teams.
“Now seven or eight teams are taking care of production, but spread out and scattered throughout the nursery,” Lewis says.
At Manor View Farm, account managers and appropriate office staff are working from home. No customers or visitors are allowed in the office and walk-in customer transactions are conducted by phone or through intercom. Jones and his team have asked walk-in customers to call in their orders 24 hours in advance of their pickup, so their orders can be pulled prior to their arrival. Manor View’s yard salesmen are following CDC guidelines and wearing masks. Despite the difficulty, the nursery is making sure there are clear lines of communications with all staff and customers.
“The health and safety of staff and customers is taken seriously,” Jones says. “We have always worked hard to make sure our customers are successful and during these difficult times it is even more important to help customers be successful and safe.”
Production staff at Walla Walla Nursery and North Creek Nurseries are practicing social distancing and wearing masks, and sales staff are working from home. The indoor lunchrooms are closed lunch breaks are staggered.
Effect on the labor pool
Uhland’s nursery is running on a skeleton staff — a result of his workers from Mexico being held up at the border and unable to enter the United States.
“I have not and will not be able to get any of my workforce until everything is cleared in Mexico and the U.S. No one can or will give me any time frame, including my immigration lawyer,” he says.
In the interim, he hired a couple of college students that were home from Penn State.
At Midwest Groundcovers, labor has not been severely impacted. Orum-Keller says that some workers have chosen to take leave due to coronavirus concerns but for the most part, the nursery is fully staffed.
Jones notes that H-2A visa processing seems to be taking priority over H-2B visas. While good news for the nurseries that rely on the H-2A program, the H-2B supplemental visa program is put on hold once its cap is reached. The H-2B cap for the second half of fiscal year 2020 was met on Feb. 18. That included 33,000 visas for worker petitions requesting a start date before Oct. 1, 2020. Jones says many of Manor View Farm’s landscape customers that were capped out after the first lottery do not have their H-2B crews. Those that were successful in the lottery and are able to get consulate interview waivers have started to see H-2B visa crews show up to work.
Sales and production
Manor View Farm did not have a drop in March sales to landscape contractors due to the spring season starting earlier than normal. Jones says April sales will depend on whether landscapers are allowed to continue working. There have been a few orders cancelled and some have been delayed.
Jones also says his crews are not behind in production as the season is ahead of schedule.
“Field digging of deciduous plant material is just about finished,” he says. “We are still planning to start planting once the weather cooperates.”
Orum-Keller expects lower than typical spring sales for the industry as a whole.
“Absolutely,” she says. “We expect garden centers to be most severely impacted negatively but landscapers are operating at a reduced pace — both due to their customers and employees impacted by the coronavirus — but also due to not having their workers fully staffed.”
She says Midwest is not behind in production operations but is behind in sales which has caused the company to pause some of its purchasing and potting. This type of chain reaction will be common among growers.
“We are looking at our current purchase orders for liners and are reducing some of these,” she says. “Our vendors are being flexible, and we are grateful for that.”
She also will likely postpone some potting in the near future, depending on the product and anticipation of demand as the market responds.
JLPN’s Lewis says his sales are down about 5%, but it’s not from the pandemic, but because the tree market is experiencing some oversupply. He estimates there’s a 15-20% overage in the market right now, which may decrease once the nation is on the other side of this crisis. Unlike the days during the Great Recession, he is not hearing about growers slashing prices or competing on price.
Production is going full speed at May Nursery in Havana, Florida, although the effects of the various quarantines have caused a 15% drop in sales during the last three to four weeks compared with the same time last year, reports Richard May, president and general manager.
“We’ll be closely watching the U.S. housing starts reports for the next three or four months,” he says. “If the housing numbers stay steady, we’ll be OK. If it starts a precipitous fall, then we would look to start tightening up on production.”
The supply chain situation
The COVID-19 challenge has ramifications on the supply chain, as well, even impacting the way plants are sold.
At Manor View Farm, Jones’ crew is limiting incoming delivery of plant material for the landscape distribution center to largely material that is already sold. This has created more of a “just in time” inventory system. Jones says the system reduces risk but can increase anxiety for the sales team when incoming deliveries are unexpectedly delayed. He says growers have been very understanding when they realize an entire spring order is not going to be taken in March but spread out over two or three shipments.
“Cash flow is king,” Jones says. “We need to limit the amount of unsold material sitting in the yard at any given time. Our goal is to keep cash flow fluid — if our customers keep paying us, we can keep paying our vendors. We are all in this together and our successful navigation of the current crisis will help determine the success of our customers.”
Montanez says that many of his landscape contractor customers have postponed some jobs, especially the larger companies who make their money on commercial installations. However, the smaller contractors who primarily serve the homeowner market are not only on track but taking on new customers. He expects the landscape trade to ramp back up in the summer, although that depends on the weather.
“If they wait until fall to complete landscape installs, it will cause a backlog. I think a lot of these jobs that have been postponed now will be back online in the summer,” he explains.
Loma Vista’s trucks are delivering product and simultaneously Oestmann and her team are “evaluating everything from staffing models and outdoor growing technologies to innovative software and webinar education and training. [As] a premiere grower for the Midwest marketplace, we’re looking at distribution routes and service channels for creative, cost-effective alternatives that expand on solutions we’ve already put in place.”
A monetary lifeline
Features - Financial Aid
If your business has taken a financial hit from COVID-19, these federal, state and private programs will help you navigate through the current storm.
It may be years before we clearly understand the economic impact on the horticulture industry as a direct result from the novel coronavirus, or COVID-19. As with any emergency or disaster, whether it’s a hurricane or recession, there’s a good news-bad news element. The good news is that consumers have been sheltering in place at home, which has created a surge in gardening interest and purchases. Social media is bursting with photos, ideas, videos, hashtags and memes related to plants, both ornamental and edible. Some growers report their IGC customers had record sales in April. (See what nursery crop growers said about their business and regions starting on page 8.) The bad news is that some states (at press time), particularly Pennsylvania and Michigan, would not allow IGCs to operate at all, while others permitted IGCs to operate under certain circumstances that conformed to social distancing mandates. In true green industry fashion, many retail garden centers have found ways to continue business with curbside pickup or delivery after online or call-in orders have been placed.
With nearly the entire country on pause, there are some cash flow issues in the industry and some payments for plants have slowed. There have been reports of some shipping hiccups with the demand for grocery shipments at an all-time high.
The federal government reacted with relief funds for small businesses. Please understand that these programs are subject to change quickly. Check the websites we’ve provided, as well as with your bank and accountant for additional help.
SBA Economic Injury Disaster Loan (EIDL)
The SBA’s EIDL program is for any small business with fewer than 500 employees affected by COVID-19. The Senate relief legislation passed in late April authorizes agriculture/horticulture businesses to apply for the EIDL. That legislation was expected to pass the House at press time. The program includes a $10,000 emergency grant and $15,000 in low-interest loans.
Businesses in certain industries may have more than 500 employees if they meet the SBA’s size standards for those industries.
According to a K Coe Isom and AmericanHort webinar in April, EIDL can be used along with Paycheck Protection Program (PPP) funds, but you are not permitted to use it for the same expenses as the PPP. In other words, if you’re making payroll with the PPP, you are not permitted to use EIDL monies to also make payroll.
The EIDL covers operating expenses and working capital, including rent or mortgage payments. It can be used for payroll if you did not receive PPP funds. It may also be used to provide sick leave to employees unable to work as a direct result of COVID-19.
Interest rates are 3.75% for small businesses with a maximum payback period of 30 years.
The USDA will receive $9.5 billion to deliver agricultural sector relief. The funds are supposed to include assistance to specialty crop producers, according to Craig Regelbrugge, senior vice president at AmericanHort. The association sent a letter to Ag Secretary Sonny Perdue in early April asking that the funds be divvied up fairly, as the nursery and floriculture sector is valued at more than $16 billion, the letter states. Watch www.americanhort.org/Coronavirus for updates.
Main Street Lending Program
The Federal Reserve’s Main Street Lending Program seeks to assist banks in extending credit to small- and medium-sized businesses which were in good financial standing before the crisis by offering four-year loans to companies employing up to 10,000 workers or with revenues of less than $2.5 billion, according to AmericanHort. Firms seeking Main Street loans must commit to make reasonable efforts to maintain payroll and retain workers as well as following compensation and other restrictions that apply to direct loan programs under the Coronavirus Aid, Relief, and Economic Security Act (CARES Act).
Employee Retention Tax Credit
The Employee Retention Credit is a refundable tax credit against certain employment taxes equal to 50% of the qualified wages an eligible employer pays to employees after March 12, 2020, and before January 1, 2021. Eligible employers can get immediate access to the credit by reducing employment tax deposits they are otherwise required to make. Also, if the employer's employment tax deposits are not sufficient to cover the credit, the employer may get an advance payment from the IRS.
Many states have COVID-19 relief funds for small businesses. Check with comptroller offices, economic development departments (www.eda.gov/resources) and state legislatures.
For example, the state of Pennsylvania is offering the COVID-19 Working Capital Access (CWCA) Program, administered by the Pennsylvania Industrial Development Authority. North Carolina launched a public/private partnership that provides loans through the North Carolina COVID-19 Rapid Recovery program. Michigan’s Economic Development Corporation created the Michigan Small Business Relief Program that provides up to $20 million in support for small businesses. The funding is divided between $10 million in small business grants and $10 million in small business loans.
Dig down into potential county and city funds, as well. Local chambers of commerce may be reliable sources.
Reducing runoff
Features - Production
Researchers are looking at ways dolomite and micronutrient fertilizer may reduce phosphorus runoff from container plants.
Jacob Shreckhise collects drainage water from columns containing pine bark growing media to determine how dolomite and micronutrient fertilizer amendments affect different forms of phosphorus.
Phosphorus runoff, including that from container-grown nursery crops, can be harmful to water quality. Because of this, researchers are looking into ways nurseries can keep phosphorus where it belongs — in the pots. Jacob Shreckhise of the USDA’s Agricultural Research Service has been looking into this problem.
"Specialty crops, including ornamental plants, small fruits and fruit trees, may spend all or a part of their life in a pot or container," Shreckhise says. "Growing plants in containers saves space, helps with shipping and handling, and requires no arable land. These containers are usually filled with peat or bark instead of soil. Because peat and bark provide very little nutrients, plants are given fertilizer that release nutrients slowly over time."
However, little research has previously been done to determine what additions to the peat or bark might help keep the phosphorus in the containers. To help answer this question, he and other researchers performed a laboratory study on pine bark-based potting medium and two ingredients nurseries often add to it: dolomite and micronutrient fertilizer.
"It's important to remember that the growing media used to produce nursery crops in containers is totally different than the field soils other crops are grown in," says Shreckhise. "Bark and peat-based growing media can't stop the phosphorus from moving around as easily. So, it's free to drain from the containers when they are watered. That's what we are trying to prevent."
For their lab experiment, Shreckhise and his team filled columns with the potting material, a fertilizer and ingredients thought to help with keeping phosphorus around. Then, they watered the columns and collected the drainage water to analyze.
Milled pine bark, a byproduct of the lumber industry, is the basis of most growing media used to grow shrubs and trees in containers.
Source: American Society of Agronomy, www.agronomy.org Photos by Jacob Shreckhise and Alex Niemiera
They found that the two additives, dolomite and micronutrient fertilizer, reduce the concentrations of a particular form of phosphorus by an average of 70%.
The additives work because of complex chemistry. Phosphate, a form of phosphorus that plants can use, has a negative charge. This means it likes to stick to things with a positive charge, such as dolomite and micronutrient fertilizer. In addition to improving plant growth, this research shows that these amendments help keep phosphorus in the pot.
Shreckhise and his team also studied how long dolomite and micronutrient fertilizers help to retain phosphorus in containers. Their next step is seeing if that retained phosphorus is in a form that plants can use.
Phosphorus runoff is becoming a bigger and bigger problem for the environment. Farms, including nurseries, must continue to combat it. "This research shows that we should continue exploring the use of amendments to help reduce the phosphorus that washes away from the containerized plants," he says.
"This research was just the first step toward understanding the phosphorus chemistry occurring in these pots," he adds. "Since plants were not involved in this study, we cannot make specific recommendations to growers based solely on this research. The general public should know that nursery growers routinely add these amendments to the potting medium. This is a step in the right direction to keeping the green industry 'green.'"
