Teach Your Staff To Avoid Overwatering

Why does something as simple as watering a plant become an issue for growers each year? We growers know our crops and read all the culture guides, but when the time comes to turn our people loose with hoses each season, problems arise.

I’ve come to the conclusion that far more plants are lost each year to overwatering than to underwatering. I truly believe the people we all hire each year are good people who want to do a good job caring for our crops. But human nature puts such a fear of drying down a plant and killing it into their heads that they overwater and kill the plants with kindness (instead of through neglect). This excess care can cause issues, including little or no root growth, high or low fertility levels, various fungal or bacterial diseases and undesirable plant habit.

The Yin/Yang Of Plant Care

There are occasions when a plant care person will severely dry a plant to a damaging level. This situation usually occurs in one of two scenarios: 1) The person has been told to grow drier and pushes the plant too far in the other watering direction (welcome to the land of yin/yang watering care), or; 2) due to a rapid improvement in outdoor weather conditions, light and/or temperature levels change faster in the greenhouse than the plant care person can react to the plants’ response.

As a producer of both young and finished plants, our biggest issue is with watering our liner production–especially from December through mid- or late March. Not only are day lengths the shortest of the year, but the weather and light levels are also at lower-than-desired levels. We have corrected this situation by supplementing light levels with 400- and 1,000-watt high-pressure sodium lights used both in the propagation and growing-on areas.

But watering is still a point of concern. Be it on benches or flood floors, plants that are watered before they need it–or watered too heavily when they do get watered–can cause the plant growth or disease issues I’ve described.

Training & Info Are Key

So what’s a grower to do? What we’ve been the most successful with is “shadowing” new watering staff for one to two weeks, using experienced plant care people. These staff members share all the “do’s and don’ts” with the new employee and also point out their personal tricks of the trade.

What has also worked well for us is developing a printed “growers protocol” booklet that all plant care providers are given. There is a large section devoted to watering in this booklet. All new watering staff are instructed in the watering protocols, and they are also reviewed yearly with existing staff. New growing staff members are shadowed when they start and trained for one to two weeks by experienced staff members as described earlier.

We have also learned that it’s much better to water “lighter” and more frequently, if needed, in the early growing months than to water heavily and possibly too early.

Judging When To Water

The primary factor we use to determine watering decisions is usually visual. Our peat-based soil is “black and shiny” when wet, “dark brown to black” when moist, “brown to dark brown” when moderate, and “paper bag brown to light tan” when dry. Over time, we have developed crop action plans that show the stage of soil moisture at which each crop should be watered. The grower then visually “grades” the current soil moisture level and weather conditions to make his or her watering decision.

Other tools suggested to our staff are physically picking up representative plants to judge them by weight, and while doing so, removing a few from their container to observe the entire soil/root ball. Often, the uppermost layer of a container can appear dry while the largest percentage of the soil mass can be quite moist. Based on time of day and environmental conditions, delaying watering may be the best action to take in this situation.

Summer vs. Winter Conditions

We have successfully used other types of information to help fine-tune our watering staff’s accuracy. One that has worked well is to show historical graphs of day length, sunlight levels (especially for the months of December through March) and average day/night temperatures both in the greenhouse and outdoors. These graphs clearly illustrate that even when the sun is shining in the early growing season, for many growers, the quality and duration of this sunshine does not persist for long enough periods to warrant early waterings.

Finally, we take this a step further and encourage our staff to understand how summer and winter conditions vary, as do watering requirements. For instance, in the late spring/early summer, final waterings are done between 4 and 5 p.m., before going home. Typically, the outdoor temperatures are in the 80s or 90s, darkness doesn’t occur for four or five hours, and night temperatures are in the 70 to 80-degree range. In these conditions, range crops are fine in the morning.

Winter conditions are very different: The sun shines for a short period of time, especially when the greenhouse temperatures are cooler; darkness comes three or more hours earlier than late spring/early summer; and night temperatures are dramatically lower–both outdoors and in the greenhouse. So why do we as growers automatically feel the need to water as much in the winter? We train our staff to understand these different conditions and change their watering practices accordingly.

These practices have been helpful to our watering staff and I hope will be helpful to yours. Try them and fine-tune as needed. Good luck, and here’s wishing everyone a great spring!

Leave a Reply

One comment on “Teach Your Staff To Avoid Overwatering

  1. You said “The primary factor we use to determine watering decisions is usually visual. Our peat-based soil is “black and shiny” when wet, “dark brown to black” when moist, “brown to dark brown” when moderate, and “paper bag brown to light tan” when dry. Over time, we have developed crop action plans that show the stage of soil moisture at which each crop should be watered. The grower then visually “grades” the current soil moisture level and weather conditions to make his or her watering decision.”

    The problem I have (and I have killed more plants due to over watering than I care to admit) is that when you are looking at 2 to 3 gallon containers, while the top of the soil looks dry, and may even feel dry with a finger probe several inches into the pot, deeper in the pot the soil is wet.

    We have tried poking fingers into the bottom slits of the pots to see if they are wet. Not a very effective method and difficult for plants on deep shelves or tables unless you pull them off to reach them.

    We tried using moisture probes, but found that the results were not trustworthy and at times were more a reflection of how dense or compact the soil was than how wet.

    We are a very small neighborhood operation, and cannot afford to lose plants like this. We do fine from Nov until about late Feb, and then the dying starts.

    Isn’t there some other trustworthy method of telling whether to water or not? A reliable moisture meter that actually works? A litmus type stick that changes color that can be stuck into a pot? Grasping, I know. But so frustrated!!

More From Plant Culture...
Feature image The 2015 Perennial Plant Of The Year, Geranium x cantabrigiense ‘Biokovo.’

August 27, 2015

The Perennial Plant Association’s Regional Symposium Will Be This October In Dallas

The Perennial Plant Association plans to hold its Regional Symposium October 5 in Dallas, Texas, in conjunction with the All-America Selections/Home Garden Seed Association's Summer/Fall Summit held October 5 to 8.

Read More
september_grow_rodale institute

August 25, 2015

Hospitals Are Getting Into The Organic Food Business

Growers investing in the organic food movement could serve a growing new area with vegetable transplants and starts, as well as produce, as hospitals begin to prescribe healthy diets and nutrition, and even go so far as to grow their own food. As part of a new phenomenon among progressive hospitals, health professionals are beginning to realize that without health and nutrition, programs and techniques may be done in vain or worse — obsolete. As more patients seeking a healthy diet turn to nutritionists, who recommend sugar-free, alkaline diets to prevent disease and aid in recovery, hospitals recognizing this trend are taking action. St. Luke’s Hospital in Bethlehem, Pa., recently contracted with the nearby Rodale Institute to manage an organic farm, established in 2014. The hospital, part of a six-campus network, aims to provide excellent healthcare, part of which includes educating patients about the benefits of a plant-based, organic diet. […]

Read More

August 21, 2015

Proven Winners Announces Roadshow Events For 2015

Proven Winner's Roadshow Events, held across North America, provide growers and retailers with the opportunity to learn how to grow Proven Winner's newest varieties and receive information about industry trends.

Read More
Latest Stories

August 19, 2015

Greenhouse Growing Recommendations For Lobularia

Modern-day Lobularias are garden classics with good vigor and long bloom times. These growing recommendations will help keep your crop in prime condition.

Read More
Mike McGroarty, owner of Mike’s Backyard Nursery

July 29, 2015

Backyard Success: Mike McGroarty Educates Aspiring Grow…

Mike’s Backyard Nursery sits on a long, narrow, 5-acre property located in Perry, Ohio. There, customers can find a variety of flowering shrubs available, all in 2-quart pots, and all for sale for $5.97 each. Owner Mike McGroarty, a lifelong resident of Perry, says the town has a lot of plant nurseries, including 100 wholesale growers within a 10-mile radius of his house. That doesn’t discourage McGroarty, because he knows that while there are a lot of nurseries in his area, no one else is doing what he is doing. McGroarty has learned about plants — and marketing them to his audience — through decades of experience. He has never hesitated to pass along his knowledge to other growers looking to start their own backyard operations, and has created an entire program to educate aspiring growers. McGroarty Likes To Practice What He Preaches McGroarty’s operation serves as the laboratory for […]

Read More
cannabis, marijuana plant

June 27, 2015

Concern Grows Over Unregulated Pesticide Use On Cannabi…

As most growers know well, the federal government regulates all insecticides, fungicides, herbicides and other commercial chemicals used on agricultural crops. Therein lies the problem with use of chemicals on cannabis crops – so far, the feds want nothing to do with legalized marijuana. According to “Concern Grows Over Unregulated Pesticide Use On Cannabis,” a June 17 article on the National Public Radio (NPR) network by Agribusiness Reporter Luke Runyon, the lack of regulated chemicals for cannabis has left growers to experiment on their own. “In the absence of any direction the subject of pesticide use on the crop has just devolved to whatever people think is working or they think is appropriate,” said Colorado State University Entomologist Whitney Cranshaw in the NPR report. “Sometimes they’ve used some things that are appropriate, sometimes unsafe.” Denver officials held tens of thousands of marijuana plants earlier this year due to safety concerns, but […]

Read More

June 16, 2015

The Butterfly Effect: Insect’s Wings Key To Azalea Poll…

A researcher from North Carolina State University (NC State) has found that in the case of the flame azalea (Rhododendron calendulaceum), all pollinators are not created equal. In fact, due to the flower’s unique reproductive structure, butterflies — and specifically, their wings — are the key to pollination. The flame azalea is commonly found in the Appalachian Mountains, ranging from as far north as New York to Georgia in the south. Like most azaleas, the flowers are large, and have an unusual structure: both the anther (male) and stigma (female) parts are very elongated and separated from one another. NC State biologist Mary Jane Epps was interested in how the azalea’s flower structure affected its pollination. “In order for a plant to reproduce, a pollinator — usually an insect — has to spread the pollen from the anther to the stigma,” Epps says. “In the case of the flame azalea, […]

Read More
Bee on a Sedum

March 17, 2015

4 Key Pollinator Research Projects To Be Funded By Hort…

The Horticultural Research Institute will grant $125,000 in financial support for four key projects as part of the Horticultural Industry Bee & Pollinator Stewardship Initiative. The Initiative has three primary goals. First, to convene a task force to develop a bee and pollinator stewardship program, including creation of best management practices for plant production. Second, to identify and fund research that will help answer key science questions and fill gaps needed to design and refine the stewardship program. Third, to seek to positively position the horticultural community and its customers by collaborating with other compatible groups interested in augmenting pollinator habitat and protection.

Read More

March 11, 2015

Pollinator Initiative Promotes Bee-Friendly Talking Poi…

AmericanHort and the Society of American Florists are working tirelessly with the ornamental industry's Pollinator Stewardship Initiative on a number of new projects.

Read More

February 11, 2015

Infusion Technology Boosts Seed Performance, Study Sugg…

Seven-year-old wheat seed germination can increase by as much as 83 percent, according to a Vital Force Technology Study that looks at the effects of energy infusion technology on plant vitality.

Read More

February 3, 2015

American Floral Endowment Accepting Research Pre-Propos…

If you are pursuing a floriculture research project, now is the time to apply for funding through the American Floral Endowment. Research pre-proposal applications for 2015-2016 funding are due to AFE by June 1, 2015.

Read More

January 27, 2015

Marijuana’s Trajectory And Ascent To Horticultural Cr…

Marijuana growing is poised for change as growers and researchers focus on improving production practices.

Read More

December 9, 2014

Greenhouse Production: Two Years Of Basics & Beyond…

Greenhouse Grower's Basics & Beyond articles cover some of the latest news and research going on in greenhouse production. Here are article links for the last two years.

Read More
GrowIt! App Wins Gold At Design100 2014 US Mobile & App Design Awards

November 24, 2014

GrowIt! App Wins Gold At Design100 2014 US Mobile &…

The social garden app GrowIt! takes the Gold Winner award at the design100 2014 Mobile & App Design Awards.

Read More

November 10, 2014

The Perennial Farm Joins HGTV HOME Plant Collection

The Perennial Farm joins the HGTV HOME Plant Collection growers' network for 2015.

Read More

November 4, 2014

AmericanHort Publishes Revised American Standard For Nu…

AmericanHort announces the revised American Standard for Nursery Stock (ANSI Z60.1) is now available for industry use. The Standard reflects the consensus of the industry regarding how nursery stock — living plants other than annuals — should be specified and sold within the trade.

Read More

September 26, 2014

Master The Art Of Watering

Watering is elemental to healthy plants, but one of the hardest concepts for new employees to master in the greenhouse. Recommend these tips to start them off right.

Read More

September 16, 2014

Ball FloraPlant’s Las Limas Facility Provides Gro…

Ball FloraPlant’s Las Limas farm in Esteli, Nicaragua, is one year away from full production, but sales and quality from the two-year-old facility are right on track.

Read More
Erysimum 'Cheers' from Darwin Perennials

September 15, 2014

Darwin Perennials Takes Production Offshore In Bogota, …

With its recent purchase of a farm in Colombia, Darwin Perennials is ready to amp up supply of its perennial genetics, to provide growers with tried-and-true varieties and comprehensive production specifications.

Read More

July 23, 2014

Plan Now To Prevent Bract Edge Burn On Poinsettias

Reduce fertilizer and water, and allow your poinsettias to develop slowly during the final four weeks of production to avoid bract edge burn.

Read More

July 11, 2014

Growing Your Crops Above Their Base Temperature

Lowering temperature set points in the greenhouse may help you combat rising heating costs.

Read More