Enstar® AQ is an insect growth regulator (IGR) that prevents the development of target insect larvae into adults. It’s a water-based formulation that features broad-spectrum, long residual control of whiteflies, thrips, aphids, mealybugs, leaf miners, fungus gnats, soft-bodied and armored scales, and glassy-winged sharpshooters. Classified in IRAC Group 7a, Enstar’s active ingredient is s-Kinoprene. It’s labeled for use on ornamental plants in greenhouses, shade houses, lath houses, and interiorscapes. Methods of application include conventional spray, drench, through irrigation systems including drip, microjet, and overhead sprinklers, or through a fogging system.
Enstar AQ is a low-use frequent treatment product that lacks spreaders and stickers, which makes it easier to water in, says Mel Whitson, director of field technical services and training at Central Life Sciences.
Enstar AQ is easily integrated into an existing integrated pest management (IPM) program.
“Enstar AQ fits in nicely with many other products a grower may be using,” Whitson says. “The labels are straightforward and it’s a great preventive to use as the growing season begins. Applications at 14-day intervals provide consistent control without putting pressure on beneficials.”
Mavrik Aquaflow® controls insects and mites with flexible use rates, for high and low infestations. It’s a pyrethroid that offers broad-spectrum control that works through contact action and ingestion. Its active ingredient is tau-fluvalinate 22.3%, which is a flowable water-based formulation.
“A lot of pyrethroids are formulated for longer control, which can lead to issues, but Mavrik provides a clean formulation designed for application every 14 days,” Whitson says. “It’s highly concentrated, so growers use a small amount with frequent re-application.”
It’s labeled for use indoors and outdoors, for greenhouse flowers and foliage, cuttings and on ornamental plantings, trees, shrubs and plantscapes, and is gentle on plants.
“Dried residues of Mavrik are nontoxic to honeybees,” Whitson adds.
Mavrik offers both preventive and curative rates. Apply low-use rates when insects are first noticed and populations are manageable. Like Enstar, Mavrik Aquaflow does not contain spreaders and stickers, which eases application.
Mavrik Aquaflow and Enstar AQ are tank-mix partners that can be applied at seven- or 14-day intervals.
“Both of these products may also be tank mixed with a third product to get a triple effect, but like with any product, it’s a good idea to do a compatibility test,” Whitson explains.
When used at a 14- or 28-day interval, Mavrik will not put pressure on beneficials, especially with outdoor crops.
“A lot more people are using and releasing biocontrols,” Whitson says. “If you have some aphids in outdoor containers, for example, and the aphids are at the treatment threshold and you see them being parasitized, you can make the decision if you want to treat for aphids at that time.”
It’s also ideal to apply both Enstar AQ and Mavrik Aquaflow to crops just prior to shipping.
With any IPM program, avoiding resistance management is crucial.
“Avoid broad-spectrum insecticides that are applied on a calendar basis. It’s better to use narrow-range and shorter-lived products with a more targeted application,” Whitson says. “If you’re having issues with a particular insect, make sure you rotate to a different class of chemistry with each insect generation.”
Airtec Air Sprayers improve spray coverage by eliminating the waste created by high pressure boom sprayers, handgun spraying, and traditional air blast sprayers. The waste eliminated includes spray drift, material runoff, lost time, and overall spray efficiency. Airtec Air Sprayers generate high wind speed with the spray material injected in the Air Nozzle or Cannon with a standard spray tip sized for the intended spray rate. This process atomizes the spray further creating a powerful air stream of spray droplets that are then targeted directly at the plant canopy. This process creates leaf movement and turbulence in the plant canopy allowing for the spray droplets to get inside the plant where pest and disease thrive.
The elimination of spray waste by the utilization of Airtec’s Air Sprayer allows growers to use the amount of chemicals needed to achieve control rather than accounting for excess material lost to spray drift, runoff, and waste. This leads to a reduction in water usage, fuel savings, equipment savings, and labor. The Airtec Air Sprayer helps your nursery become more sustainable environmentally, operationally, and financially.
Sustainable Coverage – The accurate and targeted application of spray material with pressurized air significantly improves spray coverage throughout the plant canopy leading to better pest and disease control
Sustainable Environmentally – Reduced spray drift and runoff helps the environment
Sustainable Economically – Better coverage leads to reduced chemical cost, reduced labor, and improved plant health improving the bottom line
Airtec’s Nursery Air Booms are the ultimate in spray efficiency for a container nursery. The Air Boom’s provide superior coverage due to reduced drift improving both pest and disease control and overall plant health. Airtec’s Air Booms can apply all fungicides, insecticides, and liquid herbicides. Additionally, Airtec’s Nursery Air Boom can incorporate a granular application system allowing for all forms of dry fertilizer and granular applications. This allows for the same piece of equipment to be used for liquid and dry applications increasing ROI.
Airtec’s Nursery Cannon sprayers provide growers a more targeted solution than traditional air blast or cheap foreign made sprayers. Airtec specializes in single and double cannon sprayers designed to target the plant bed for reduced drift, increased efficiency, and a more consistent application of spray. Airtec’s Cannon Sprayers come in both big and small models sized to the size of the tractor and the spray requirements of the grower.
Airtec Sprayers has sprayer models designed for nurseries of all sizes including container nurseries, bare root nurseries, Christmas trees, tree farms, woody ornamentals, flowers, fruit plants, and all other outdoor nursery stock. Airtec Sprayers offers a full line of nursery spray equipment from small handgun sprayers, to cannon sprayers, to air boom sprayers to service all your nursery spraying needs.
Yellowhorn is commonly propagated from seed or cuttings (stem and root suckers).
Photo by Mark Dwyer
The yellowhorn (Xanthoceras sorbifolium) is surprisingly underutilized in our North American landscapes although its availability is certainly associated with its obscurity (and vicea versa). Also called goldenhorn, white raintree and Chinese flowering chestnut, this small, deciduous tree from northern China is hardy in Zones 4-7 and is surprisingly durable and long-lived once established. First collected and named in 1833, this member of the soapberry family (Sapindaceae) initially became cultivated in Europe (Paris) by 1868. Joseph Hooker, Director of the Royal Botanic Gardens - Kew (1865-1885), described this plant in 1887 as “one of the most attractive and interesting hardy garden shrubs that has been introduced in many years.” Yellowhorn has also received the Royal Horticultural Society Award of Garden Merit which should hint at its potential value and impact in the landscape.
Yellowhorn features lustrous green, compound leaves that resemble the foliage of mountain ash (Sorbus), hence the specific epithet of sorbifolium. The pinnate foliage features very narrow leaflets that are quite glossy. This plant certainly contributes a fine texture in the landscape and the fall color can range from a muted gold to a clear yellow. Yellowhorn will reach heights between 8-25 feet with a width of 10-15 feet in time and should be considered slow to moderate in terms of growth rate. This size fits right in between the loose definitions of a large shrub and small tree. With age, the form becomes more upright with a stiff, coarse branching habit although the significant flowers (mentioned below) may bend the branches to a certain degree when at peak bloom.
Specimens are frequently multiple trunks although some are single trunks and branched fairly low to the ground. Yellowhorn may slowly colonize a space with some root suckering which is not a characteristic of every specimen. The fleshy, fibrous roots make this plant challenging to transplant which is noteworthy. The commonly observed high transplant mortality seems to be associated with a sensitive root structure. Gentle handling is prudent during all phases of planting.
Blooming in May, the fragrant flowers, appearing on terminal racemes, are white with very light green streaks and a center that age from yellow on the newest flowers to a gorgeous red orange on older flowers. These proliferous flower clusters can be up to 10 inches long and individual flowers are roughly 1 inch in diameter with five petals.
Another common name for this plant is “popcorn shrub” due to the appearance of the flowers upon opening. The duration of bloom is only about two weeks, but it is a gorgeous and memorable display. Plants as young as two to three years old will start to bloom readily. William (Ned) Friedman of the Arnold Arboretum (Harvard University) writes about the value of the yellow to red color shifts in the flowers of yellowhorn and other woodies with a similar flowering characteristic. Ecologists have shown that insects have an innate preference for yellow flowers over red and by targeting the younger flowers with yellow accents, they are assured of more nectar and pollen. Those that have faded to red have likely been visited already. Friedman mentions that this yellow to red color shift has evolved to help steer insects to newly opened flowers.
The fruits, more common on older specimens, are 2 ½-inch, pear-shaped, leathery capsules. The capsules are initially green and resemble a black walnut husk but later age to a brown and split open in to three chambers that contain the glossy, pea-sized black seeds. The half-inch seeds are edible and when roasted, have the flavor of macadamia nuts. The seeds are also used to produce a quality cooking oil and aside from being roasted, can be boiled or dried and ground into flour. Apparently, this plant also has edible flowers and foliage which are traditionally boiled in advance of consumption.
Yellowhorn can be found in Beijing, China as a small urban tree and is also commonly found throughout a wide range of other urban settings. There are actually large plantations of yellowhorn in China as the seeds are showing great promise as a highly suitable biofuel.
Yellowhorn is commonly propagated from seed or cuttings (stem and root suckers). A higher germination rate for the seeds has been observed with three months of cold stratification. Soaking the seeds for 24 hours before sowing combined with scarification is also recommended by some sources.
The first challenge in growing yellowhorn initially starts with sourcing it. Finding this plant will certainly be a quest but one ultimately worth the time. This unique and beautiful woody plant has impressed those that have grown it over the many years since it was introduced into cultivation.
‘Psgan’ offers increased cold tolerance and hardiness compared to the species.
Photo by Plant Select
In the landscape
Yellowhorn doesn’t mind slight dampness but is quite sensitive to excessive moisture or heavier soils that stay wet. In general, this plant isn’t overly picky about soil although again, drainage is important. A loamy soil would be ideal but isn’t essential for the success of this durable woody plant and slightly acidic to slightly alkaline soils are just fine. A pH range between 5.5 to 8.5 is recommended. Yellowhorn is very sensitive to too much shade where it will simply not thrive or flower well. A full sun location is ideal as is plenty of summer heat associated with that exposure. This plant has no significant insect or disease problems although coral spot fungus has been observed on occasion.
Keep in mind that yellowhorn also flowers on old wood so any pruning should be accomplished immediately following the bloom cycle similar to the approach with lilacs (Syringa). An isolated yellowhorn can still flower and fruit although multiple specimens will assure more significant fruiting.
There is a variety called Clear Creek (‘Psgan’) selected by Green Acres Nursery in Golden, Colorado, and promoted by Plant Select, which markets a brand of plants designed to thrive in high plains and intermountain regions. This selection has all the same features of the species but is thought to have increased cold tolerance and hardiness.
Whether yellowhorn is used as a specimen plant, in a mixed border or as spring feature in a prominent location, it certainly deserves broader awareness, availability and enjoyment of its attributes.
Mark Dwyer was the Director of Horticulture at Rotary Botanical Gardens in Janesville, Wisconsin, for 21 years. He has degrees in landscape architecture and urban forestry and now operates a private consulting practice, Landscape Prescriptions by MD. www.landscapeprescriptionsmd.com
Avoid the clogs
Features - Irrigation
Don’t let a stopped-up irrigation system put a damper on your crops.
Clogs in an irrigation system can be managed and prevented with a few steps.
Adobe Stock
When irrigation systems become clogged, it causes production issues and negatively impacts plant growth. The good news is that it’s a manageable problem with viable solutions that growers can implement.
“We are all very aware of the importance of watering,” says Rosa E. Raudales, an assistant professor of horticulture and a greenhouse extension specialist at the University of Connecticut. “We’re also aware of the importance of not over-watering, but also [of] not stressing our plants. If you allow your system to clog, then you’re losing control because you can’t really estimate how much you’re going to water.”
The three types of clogging
According to Raudales, there are three kinds of clogging growers should be aware of: physical, biological and chemical. She says that each type has different causes and symptoms that when identified, allow growers to zero in on the problem afflicting their greenhouses.
For physical clogging, she says it involves a suspended solid backing up the system, thus preventing water from reaching the plants.
Watch for sediment or other debris from ponds that may clog irrigation systems.
Photo by Kelli Rodda
“Think about if you’re recirculating water and if you’re carrying any type of remaining debris that’s coming back from the soil,” she says. “You would expect a physical [object] that would plug your system. Mostly that would be a concern for growers who are recirculating water or maybe growers who are using pond water as their water source because it tends to be a little dirtier than other sources.”
Biological clogging occurs when biofilm builds up in an irrigation system’s pipes and slows or stops water flow, Raudales says. It is most often greenish-brown colored, giving growers a visual indicator that their pipes are clogged.
“[Biofilm] is mostly foreign debris caused by bacteria, but you can also think of it as a combination of bacteria and algae,” Raudales says. She adds that biological clogging can be the hardest type of clogging because there isn’t a comprehensive solution for it.
Emitter in irrigation booms: The filter had crystals of calcium precipitates and the cover had biofilm with algae.
Be aware of chemical clogging. Raudales says that this can be caused by different materials building up in the system, most notably iron. This type of clogging is often caused when a water source such as a well is contaminated and introduces harmful materials into the system, she says. Calcium, manganese and other materials can also cause clogging.
Different treatments for different types of clogs
Raudales says treating physical clogging is straightforward, making it the easiest type of clogging for growers to deal with. Often, the material clogging the pipe is something that can be blown out the front of the system. All a grower needs to solve this issue is pressure.
For biological clogging, Raudales says it can take a “big effort” to combat it properly. For instance, if a propagation house’s emitters are clogged with biofilm, growers must choose between a few different treatment strategies. One is to take the emitters down, replace them with clean ones and wash the clogged ones. Chemical treatments are also an option, although bacteria can become resistant to them over time.
Iron precipitates on the inside surface of a 3-inch pipe.
As for chemical clogging, the process is like treating physical clogging. Raudales says that it requires using a large concentration of the chemical being used to clear out the pipe and the line being shut down. It also requires an empty greenhouse or production area to avoid damaging plants.
The one significant factor that Raudales says links the different treatment options together is that unclogging irrigation systems is a labor-intensive process, and not all growers can take workers off other tasks in the growing operation and assign them to the problem. Cleaning the system is a necessity, even if it’s time consuming.
She suggests starting an ongoing, low-dose chemical treatment that can reduce buildup over time in the system. She also recommends installing a water filtration system.
Sales of houseplants have skyrocketed. Make sure you have enough stock for your garden retail customers.
Photo courtesy of Sunnyside Nursery
The green industry has seen an influx in houseplant hunters old and young. “It’s kind of like the sneaker people — they’re just waiting for next year's line to come out,” says Justin Hancock, head of Costa Farms’ brand and consumer marketing.
Hancock is responsible for the company’s creative efforts — plant tag designs, digital marketing, social media, website management, consumer analyzation and so forth. In today’s digital age, it is safe to say he is on the frontline of knowing who wants what and why.
Are you ready to meet that pent-up demand for your garden retail customers?
Health-backed houseplants
Compared to previous years, the houseplant trend has interested new clientele, but the plants themselves are no longer for looks and home décor. Now, they are part of a greater focus on lifestyle and health.
About two-thirds of customers who visit Sunnyside Nursery in Marysville, Washington, seek out air purifying plants, according to Holli Schippers, the retailer’s houseplant and seasonal manager.
“I think they’ve come back because of people wanting to be healthier,” Schippers says. “What I get is, ‘What can I use for air purifying plants?’ That is constant, constant, constant. People want to clean the air in their house, especially because of COVID.”
Hancock agrees. Although he believes the houseplant obsession would have resurfaced in general, “millennials in particular are really interested in their wellness and that audience has created more momentum,” he says.
Diverse door knockers
While health-supporting plants are top-sellers, air purifying plants are not the only greenery customers seek at Sunnyside. According to Schippers, shoppers look for pet-friendly options and succulents. Sunnyside also sees a host of customers with preferences for all sizes, colors, and textures, “anything from 6, 7 feet tall to a little 2-inch pot,” she says.
Because of this, she orders large amounts of plants weekly to meet the demands of her diverse clientele.
“We get everything,” Schippers says. “We get the middle aged-consumers, the millennials, the young’uns that are buying their first home and want something big for the entrance, or something little for the tabletop. We get groups of women that are in their 60s and 70s all giddy saying, ‘Look what I found,’ and I’m talking cartloads of plants. The millennials come in and shop in groups, and they’re in here every week or every pay day. Then we get the young kids that come in with their parents that are around 10, 12 years old. It’s all generations.”
Like Sunnyside, Costa Farms also has multiple consumer groups, but the most engaged consumer, Hancock says, is typically the millennial woman followed by the “core consumer — the person who’s between 45 and 50 and has always had plants.” The latter group generally has no interest in trendy varieties, but in simply nurturing their passion of plants, Hancock has observed.
While he sees a broad assortment of buyers, like Schippers, he has also noticed no favor toward one type or size of plant, but rather a focus on certain sought-after varieties instead.
“I think with the collectors it’s more about the variety than the size — getting this new plant that they’ve had their eye on for a couple of years but never saw on sale,” he says.
The digital drive
Some of the inspiration that drives the return of the houseplant craze includes changes in generational buying, and, of course, social media’s influence, Hancock says. And while he believes the houseplant craze would not be “nearly as popular if it weren’t for Instagram,” Schippers says the infatuation has always been there.
“I think [collectors] want to be trendy but it was the same before,” she says. “Back in the 1800s, a houseplant showed that you had wealth, status. So, I think it’s still a little bit of a ‘Look what I could get’ situation.”
Photo courtesy of Sunnyside Nursery
Hancock, too, has noticed the same trend, and in his own words, he calls it a “need point” for some consumers.
“With the collectors, a need point is finding new and interesting varieties. Not only to have for their collection, but also to be able to show off on social media,” he says. “I think that's as much of a driver as it is just having it.”
The digital drive is also accompanied by a new way of shopping, ordering and delivering. Because of this, Costa Farms established an Amazon store to reach more customers. For some, partnering with the massive online shopping platform is out of the question, but Hancock has another perspective.
“It certainly makes plants more accessible, especially for consumers in small towns where they may not have a large store that buys from us,” he says. “And then, I also suspect that it's really utilized in dense urban areas where they have stores, but it may be a pain to go out and schlep your plant, your pot and your potting soil back to your apartment.”
To trend or not to trend
Although Costa Farms keeps its eye on trends, Hancock says they are careful about which ones to follow and they try to establish a leadership position instead, allowing them to maintain value in their selections.
“Just because a variety is popular today, that doesn't necessarily mean that we might try to chase that one,” Hancock explains. “But we might look for the criteria that we think will lead to the same level of popularity in other varieties, especially if it's one consumers aren't familiar with, or if it’s not particularly well-known in the trade.”
Selecting what fads to follow also allows Costa Farms to balance its wide buyer pool. Because there are still a lot of entry-level consumers, the company continues to focus on easy care plants like Sansevieria, Zamioculcas and ponytail palm, for example. Hancock also references cacti and succulents, although he does not think they are necessarily as easy to care for as most consumers assume.
With the more engaged consumer, however, Hancock has seen a “heavy swing” toward trendy varieties like Monstera deliciosa, M. adansonii and Ficus lyrata, for example.
Photos courtesy of Costa Farms
While Costa Farms is selective with the trends it follows, Sunnyside seeks out its own niche by appealing to the plant parents who are looking for rare finds. Luckily for Schippers, her natural affinity for “things that are weird, unusual, hard to get and colorful” is a perfect fit for Sunnsyide’s wide array of houseplants.
Full of “interesting-looking plants that can be a conversation starter in your home, or something that just makes you smile when you see them” Sunnyside’s website boasts some distinctive plants in that category including Monstera adansonii, Columnea gloriosa (goldfish plant), and Ceropegia woodii (string of hearts).
When Schippers runs across hot commodity plants like these, she buys them up with no hesitation.
“There are so many houseplant forums with people looking for hard-to-come-by plants that come in on a regular basis. So, when I find something that’s hard to come by, I don’t even look at the price because I know it will sell,” she says. “People will spend what they want to on the more unusual, hard-to-come-by things.”
The future of indoor foliage
Compared to previous years, Hancock says Costa Farms is planting more of its Trending Tropicals collection ¬which he describes as “the newer, more collector-y plants.”
He attributes that to the entry consumers’ rise in ranks.
“I think we’re seeing more and more consumers move up that continuum, starting at, ‘I’m an entry level consumer and I got a couple plants,’ to ‘I’m having really good success with the plants, let me get a few more.’ And then suddenly, ‘Alright, I need this new exclusive one.’ It’s kind of a need for some people.”
But, to know if the houseplant trend will continue or cease like it did back in the ‘70s is “the million-dollar question,” he says.
Hancock also says that because social media is fickle, sometimes trends that originate there tend to fizzle out quickly. Whereas in pre-social media days, the rise and fall of fads were slower. Still, he does not see any sign of the houseplant craze stopping. Schippers agrees.
“I think, like anything, it might slow down, but I don't think it will disappear,” Schippers says. “I think it may slow down like it did before, resurge and be popular again. But we’ve got a long wave to ride right now.”
Sierra Allen is the assistant editor at sister publication, Greenhouse Management.