Plant nutrition is a very important aspect of producing quality plants for the marketplace. The supply and absorption of chemical compound required for growth and plant metabolism is defined as nutrition, and chemical compounds required are referred to as nutrients.

Plant nutrients are: Carbon (C), Hydrogen (H), Oxygen (O), Phosphorus (P), Potassium (K), Nitrogen (N), Sulfur (S), Calcium (Ca), Iron (Fe), Magnesium (Mg), Molybdenum (Mo), Boron (B), Copper (Cu), Manganese (Mn), Zinc (Zn), and Chlorine (Cl). Lately, Silicon (Si) has been shown to provide some benefit in disease resistance and drought tolerance, and a number of potting media producers are putting silicon into their products. C, H, and O are generally derived from the atmosphere, while the others need to be provided in the potting medium or by supplemental fertilization.

Finding the right fertilizer

Many choices of fertility are available to a grower, with a good array of product formulas available. Both time-release products, such as Osmocote or Nutricote, as well as liquid soluble formulas, are options a grower can elect to use in a crop fertility program. Often Ca and Mg are incorporated in peat-based media as limestone in order to adjust the pH by the manufacturer. In many cases, this incorporated nutrition is adequate for the crop cycle, but with some plants, additional doses of Ca and/or Mg are required. Plants such as bacopa, calibrachoa and petunia are iron-inefficient uptake plants, and may require pH adjustment or additional applications of iron to finish well. Iron chlorosis can become a problem with these crops when pH or Fe availability are not adjusted properly.

Water condition considerations

By conducting a test of the water used for the crop irrigation, a grower can determine the alkalinity of the irrigation water and the pH of the water. Then, by using an alkalinity calculator such as the excellent online one from University of New Hampshire (bit.ly/28JxBIb), a grower can design the required pH adjustment for a good fertility program. Many operations inject acid into their water for irrigation to provide a proper pH for their crops in central Pennsylvania, with well water pH levels above 7.0.

Finishing phase fertilization

A number of flowering plant crops are grown with a finishing phase of production where nutrient levels are reduced to help tone the crop in its final phase. This practical approach to crop culture has been well-researched and documented over a number of years.

Plants like petunias, which are known to be fairly high-fertility requiring plants, are generally grown at 150 to 200 ppm N on a constant feed basis, or 1.0 to 1.5 mmhos/cm EC (based on a 2:1 extraction method). Recommendations for the finishing phase of petunia culture are to reduce the feed rate by half in the last two weeks of culture.

Perennials have also been successfully treated with this strategy, and plants grown at 136 ppm N were shown to be just as high quality when the rates were reduced to 75 to 80 ppm N in the final phase of crop cycling. A grower using this strategy would be aiming for an 85- to 95-percent level of fertility maximum for the peak growth phase, subsequently reducing the rate to half of the maximum for the finishing phase. Compared to a constant feed program, cycling can save money, reduce environmental impact, and growers can do this with a number of crops.

Ensuring success in big-box plants

In producing plants for the big-box stores, where crop fertility maintenance may not be as carefully tracked as with an independent operation, some important considerations need to be addressed. Usually, the shipment arrives from the producer company with a good fertility status. But if supplemental fertility and proper watering practices are not followed, the shelf life of that crop will be limited.

For example, two such big-box operations exhibited tomato plants at the beginning of June that were totally flagged and dehydrated after two days of considerably high winds. Many of these operations have the plants in exposed conditions, and natural rainfall also leaches nutrients. Obviously, watering was not carefully attended to at those locations, and supplemental fertility is not typically provided after receiving the plants from the grower either. This creates a situation for the big-box operation supplier, where the plants, although grown properly in production, will diminish in quality the longer they remain in the big-box store. The consumer, who is unlikely to provide additional fertility after purchasing the plants, will wind up considering the plants of inferior quality as they become chlorotic, and growth diminishes over time. While the producer was in no way at fault, the consumer’s tendency may be to blame the producer company, and not the big-box store maintenance program. The consumer frequently is not informed about the production system that makes it possible for plants to come to the marketplace, which could lead to further misinterpretations.

In an independent garden center, the consumer is usually informed of the need for supplemental fertility once the plant leaves the greenhouse or nursery. Many independent operations provide a good array of fertilizers for their consumers, and are quite likely to inform the purchaser of the proper fertility requirements for the plant they are purchasing.

Overcoming challenges

One strategy that may work to overcome this problem is to feed at a higher rate than typical prior to shipment to the big box. Plants that are sold in pots and hanging baskets can be provided with a time-release fertilizer product prior to shipment to the big box store. This fertility should be selected for minimum of four months duration, and a number of these time-release products can provide fertility for intervals longer than four months.

One such choice could be Osmocote tablets, which claim eight- to nine-month longevity, and have demonstrated this claim successfully in the Penn State Flower Trials where many of the plants are grown in 5-gallon containers. Proper fertility is provided through the summer and into early October with this strategy. Supplemental fertility is added as needed by using liquid soluble formulas, injected through the irrigation system. By monitoring the pour-through leachate, and taking potting media samples and tissue samples throughout the growing cycle, these levels can be recorded and adjusted as required. This is precisely what most growers are currently doing in our industry.

Such careful management of fertility is not applied at present in a big-box situation, as the leachates are usually not being monitored and levels adjusted by staff at the store. Certainly there are watering issues at times as well. These issues, coupled with the lack of information on plant care usually dispensed, result in an unsuccessful experience in many cases for the consumer.

To mitigate those problems, it can be very useful to supply time-release fertilizer in the pot to carry that plant through the growing season. If this is impractical with a product such as a pack or flat, consider getting custom blended feed incorporated in the potting medium. If custom blending of media is not practical, then at least finish the product with a rate 85 to 95 percent of maximum liquid feed rate. This fertility management program gives the product the best possible opportunity for success in a situation where crop maintenance may not be properly carried out.

Sinclair is an extension educator at Penn State University specializing in floriculture, propagation, breeding and nutrition.

Thielaviopsis root rot is also called black root rot and it has a long history on tobacco plants and hollies in addition to bedding and flowering potted plants. In the greenhouse, we see it most often on calibrachoas, pansies, vincas and petunias. Infected plants usually are stunted. Leaves turn yellow or purplish because of dysfunctional roots — iron applications won’t help. To get the right diagnosis, look at the big picture. If a crop is uniformly yellowed, it indicates iron deficiency from too high a pH. However, small plants with purple or yellow leaves are scattered through a crop, rinse and examine the roots with a microscope or send a sample to a diagnostic lab to check for the Thielaviopsis fungus. Always check the roots of plugs as they come into your greenhouse to make sure you aren’t inviting in black root rot. Never reuse trays after an outbreak without disinfection.

Margery is a plant pathologist specializing in ornamentals at Cornell University’s Long Island Horticultural Research & Extension Center. She can be reached at mld9@cornell.edu

Annual bedding color trends ebb and flow, just as most trends in business do, no matter the industry. Flower color and form preferences move with fashion and design trends, while economic factors impact spending on plant size and volume. These days, the hunt for added value and benefits is driving annual bedding demand.

Small opportunities

Pre-recession, landscape contractors were still planting big swaths of traditional annual bedding color and often doing a couple of major change-outs a year. Customers were willing to spend readily to keep up with the Joneses. On the flip side, garden center retailers were able to push bigger bedding plants with bigger price tags without too much resistance, dependent of course on their market demographics. Customers increasingly wanted instant gratification, which meant a willingness to start with bigger and more expensive specimens (quarts and gallons versus 4-inch pots). In hot climates, a push for bigger plants was also a logical one, as small bedding plants often fail to thrive when planted during the heat, leading to customer failure and returns.

The big color change-outs, and the bigger plant and price tag push, became tougher sells post-recession. Since the recession, the only plant category that has steadily clocked measurable sales growth is that of edibles. Despite the economic recovery, and positive outlook for green industry sales, many customers are still applying caution and thought to their annual bedding purchases. Therefore, smaller bedding plants, which come with a smaller price tag, have regained some of their appeal.

DIFM

Budgetary caution aside, many consumers are still valuing their time and plant benefits over the price tag, leading to an increase in DIFM — Do It For Me. According to Chris Ricci, vice president of sales of outdoor products at Green Circle Growers in Ohio, “The biggest shift in bedding has been from do-it-yourself to having it done for you.” Ricci asserts that it’s just easier for consumers to buy finished color planters than assembling the combos themselves. “We can put combinations together and know what goes well together in them,” Ricci says. Green Circle customers are also willing to spend more on more expensive brand name plants, as they perceive these offer more variety and color.

Less is more

In hot and dry climates, where drought has had a significant impact on planting trends, landscape contractors have been asked to trade out seasonal color plantings for perennial, water-wise plantings. Johnette Taylor, owner of Roundtree Landscaping, Inc. and immediate past chairman of the Board for the Texas Nursery & Landscape Association, notes significant shifts, but also opportunities.

“The main trend with our customers is fewer annual color plantings. But that is actually playing out in two different ways,” Taylor says. “Firstly, some clients are cutting out annuals for more perennials and others are choosing more blooming shrubs and groundcovers.”

While Taylor acknowledges that customer demand has shifted away from the desire for large swaths of annual bedding color, she also points to emerging opportunities. A secondary effect of planting smaller pockets of color is that of more frequent color change-outs. “What used to just be one begonia planting in spring and pansies in fall has become three, four or five changes per year, so color is always new and fun,” Taylor says. In her words, less can become more.

What’s popular?

When it comes to which annuals are now most popular, Taylor says vinca, geranium, begonia and caladium still top their customer favorites list. However, that is often dictated by what growers are offering. Even so, less “tight” annuals such as angelonia and pentas have become much more popular with Roundtree’s customers. They’re also now more open to less traditional tropicals, such as plectranthus, cordyline and alocasia.

Carol Allen, horticulturist and designer in the Washington, D.C. area also highlights the demand for tropicals as bedding color. “In the hot, humid mid-Atlantic, I’m seeing more tropicals for back of bed or as focal points. Many are deer resistant, too,” Allen says. Another trend she notes is an uptick in the use of perennial salvia varieties as the mainstay for spring, summer and fall bedding color in place of more traditional annuals.

Succulents and foliage plants are also coming into their own as bedding color. “Consumers are looking for something different. [They] are looking at foliage, tropicals, edibles, succulents and almost anything [except] the same thing they see every day for so many years,” says Lloyd Traven, owner of Peace Tree Farm. “Differentiate or die,” Traven says.

Who does it feed?

As edible landscaping, or foodscaping, has continued to grow over the years as a favored and accepted gardening approach, and planting for pollinators continues to dominate the media, consumers are asking more and more of their “bedding plants.” Do they have to be just for color? Or, can they serve a greater purpose in terms of feeding both the home dwellers and the local wildlife, whilst still offering beauty?

While many of us in the industry have been practicing edible landscaping, foodscaping or urban farming (call it what you will) for quite some time, it’s still a growing market with consumers. While my own edible landscaping approach used to seem very foreign to my neighbors, and city officials, it’s now becoming a landscape style many homeowners aspire to. However, many city authorities and homeowner associations still do not approve. Local laws and homeowner association rules can make it increasingly difficult for edibles to be grown street-side. Even so, both home gardeners and the industry are still pushing the edible and plants-with-benefits movement forward.

When it comes to the classic flat of annual color, why can’t that color come from edibles? Re-purposing compact edible plants as border color has a lot of potential in the market place. It’s also a great way to “sneak” in edibles as part of a more conventional looking color planting. By using edibles with significant ornamental value, consumers can get the most for their money and offset neighbor and city concerns. When it comes to bedding breeding, that’s where there is a huge opportunity: plants that are so attractive it’s not obvious they’re also an edible crop. Some of the large-flowered strawberry varieties hitting the market over the past few years are stunning ornamentals in their own right. The fruit becomes an added bonus.

When it comes to bedding breeding, that’s where there is a huge opportunity: plants that are so attractive it’s not obvious they’re also an edible crop.

While landscape contractors may be a bit slower to dive into the edible bedding market, and selling it to their customers, some are coming around. “I have been thrilled by the interest of North Carolina landscapers to include seasonal edibles in entryways and commercial plantings,” says Brie Arthur, a green industry communicator based in the state. “Rice has been a big hit as a replacement for annual pennisetum; peanuts and strawberries are being used as bed edgers with traditional annuals mixed in like coleus and begonia.” In her market, Arthur feels foodscapes are finally starting to take off as local food production becomes a more important issue for residents. Read “Think outside the (raised) box” in the May 2016 issue of sister publication Ornamental Breeder at magazine.ornamentalbreeder.com to learn more about her efforts to support the foodscaping movement.

As always, boosting such sales comes down to good customer education and marketing. Most retail customers might not even think of using colorful lettuces or strawberries as a bed color border, unless you sell them the flats of such plants in that context. As a grower, are you identifying the edible crops you go that also serve well as bedding plants for your retailers? As a retailer, are you merchandising edibles in your bedding areas?

Bee beautiful

Crystal Cady, owner of Sunflower Acres Farm & Garden in Salem, Ore., offers up her customers’ desire for color with a purpose. “As a grower-retailer, the two biggest trends I have seen in my area that are driving annual sales are consumers want plants that: 1) provide value and 2) offer benefits to the visitors to their garden beyond them and their pets.” That is, pollinator visitors.

As consumers become more pollinator savvy, they aren’t looking just for a pretty petunia to frame the garden. They’re starting to ask if that petunia has value to pollinators and how it was grown. “Each year we have been growing more and more annual varieties that are pollinator-friendly,” Cady says. “We have always used beneficial insects, no pesticides, and organic [fertilizers] on our veggies and herbs.”

Not all cultivated varieties offer up the same foraging potential as “native” plant species. When choosing varieties for your bedding assortment, keeping a focus on good pollinator plants can help your retailers and contractors boost bee-friendly bedding sales.

Mix it up

It’s not just retail customers who want to buy ready-to-plant mixes. What Roundtree Landscaping is really looking for from growers these days are bedding mixes that are already put together and share similar growing needs. “I want pre-grown mixes for a ‘plop and drop’ in landscape planting,” Taylor says. In addition to mixes specifically grown for shade, sun, dry or wet conditions, Taylor is also seeing a demand for a more “native look,” which is right in line with the trend of landscapes becoming less formal. While that type of product assortment has become more common for containers, we have yet to see it translate into the landscape bedding category.

It’s not just ready-to-plant mixes that would benefit your home gardening and landscape contractor customers. Combinations that flower in a succession are also in demand. “The best help we could get from growers would be pre-made mixes and ideas on annuals that bloom in succession, but can all be planted same time,” Taylor says.

The clear message here is that variety itself rules, and it’s time to think outside the conventional bedding box. The palette of plants that can now be considered for use as bedding color is expanding. As long as the plants serve the purpose of the buyer and offer up the added benefits they want, there’s a lot of room for experimentation.

Leslie (CPH) owns Halleck Horticultural, LLC, through which she provides horticultural consulting, marketing strategy, digital content creation, branding design, advertising and social media support for green industry companies. lesliehalleck.com

It’s been called “the Rolls Royce of houseplants” and has won numerous accolades at tradeshows and plant exhibits. Once you see it, you can’t help but agree: Medinilla is a beautiful display of cascading pink flowers, and a shade-loving outdoor and indoor plant that evokes feelings of elegance and drama.

While its origins hail from the mountains of the Philippines, Medinilla has also been cultivated and grown in royal conservatories. Available in both single- and double-bloomed varieties, Medinilla is offered as pre-finished 6-inch pots through the Ball Ingenuity program at Ball Seed. Here are a few helpful guidelines to create fantastic plants with a long window of color.

For more, visit ballingenuity.com

Kevin is head of new product development for Ball Ingenuity at the Ball Seed Company.

Temperature Requirements

Flowering time from a pre-finished budset plant is primarily determined by 24-hour temperature.