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.

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.

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.

“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.

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.

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.

For more: Rosa Raudales, rosa.raudales@uconn.edu

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.

Echinacea, commonly known as coneflowers, are among the most iconic and recognizable native plants in North America. The earliest documented horticultural use of Echinacea can be traced to the late 17th century when Echinacea purpurea seeds were sent to England by the Virginia clergyman and naturalist John Banister. Medicinal use dates back even further as Native Americans used Echinacea to treat a variety of ailments, a tradition that has carried into modern times.

The nine species of Echinacea are North American natives and predominantly occur in the central and eastern United States. The majority of wild coneflowers display pink, purple, and rarely white flowers from late spring to summer. Only one species, Echinacea paradoxa, breaks this color trend and produces canary yellow blooms in June. Dr. Jim Ault of the Chicago Botanic Garden was among the first plant breeders to intentionally cross multiple species in the 1990s. Since that time, the breeding and selection of coneflower species has further unlocked the horticultural potential of this genus resulting in a staggering variety of new cultivars in American and European horticultural markets. Today, Echinacea are available in an array of colors including, white, yellow, orange, red, pink, purple, and even green.

Double, or pompom, flower forms also add to the diversity of coneflowers.

Although common in gardens, some coneflowers are threatened in the wild. Echinacea laevigata is federally endangered due to habitat loss and the suppression of fires that are key to its survival. Echinacea tennesseensis was also considered endangered but was delisted in 2011 thanks to conservation efforts.

However, it still only exists in a relatively small range in Tennessee. Other species, particularly Echinacea angustifolia, are under pressure from unsustainable wild harvests due to their purported medicinal qualities. Thankfully, an increased availability of commercially farmed Echinacea has reduced some of the stress on wild coneflower populations. To ensure the future of wild coneflowers, it is important to only purchase commercially produced herbal supplements and nursery propagated plants.

Echinacea, like the previously trialed Coreopsis and Helenium, are members of the aster family (Asteraceae). An Echinacea “flower” is a composite inflorescence made up of hundreds of individual ray and disc flowers, or florets. Fertile disc flowers form the center, or cone, of the flower. Each disc flower is accompanied by a single spiny bract that together gives coneflowers their signature bristly appearance. In fact, the genus name Echinacea originates from “echinos,” the Greek word for hedgehog. Individual disc flowers are short lived but collectively offer pollen and nectar to pollinators or an average of five weeks from late spring through summer.

The individual colorful “petals” of Echinacea blooms are actually specialized ray flowers that serve to attract pollinators. With ray flowers included, most coneflower inflorescences range from 3-5 inches in diameter.

Double-flowered Echinacea represent significant breakthroughs in coneflower breeding that have increased the variety of the genus in the horticultural market. They have become popular in gardens because of their showy flowers and prolonged bloom times but have proved to be less favored by pollinators.

Echinacea are clump-forming herbaceous perennials that emerge each spring to form a lush rosette of lanceolate foliage. Some species, including E. purpurea, produce leaves with relatively few foliar hairs while others, like E. pallida and E. tennesseensis, are densely pubescent. In mid- to late spring, flowering stems push their way above the basal foliage and eventually reach a height of 2-4 feet depending on the species or cultivar. Seeds ripen in late summer and are readily consumed by birds, particularly goldfinches.

Most coneflowers produce taproots that allow them to grow in competitive habitats where water is at a premium. In contrast, E. purpurea produces roots that are more fibrous and are consequently better suited for average garden soil. All coneflowers, however, require soils that are well drained to persist and thrive in a garden setting.

Echinacea top performers

A few coneflowers, specifically Echinacea purpurea ‘Pica Bella’ and Echinacea purpurea ‘Fragrant Angel’ were included in our 2007–2009 and 2018–2020 Echinacea trials and constituted some of the best performing plants in both evaluations. Top performing Echinacea overall had sturdy, semi-compact habits that resisted flopping and largely omitted the need for staking, a trend that was also observed in our first evaluation of the genus.

One common problem with coneflowers is that some do not live long in the garden. It has been theorized that cultivars grown from seeds are longer lived and generally more vigorous than coneflowers that are produced clonally in tissue culture. Unfortunately, due to the infection rates of a disease called aster yellows (see full report mtcubacenter.org/trialgarden) it was difficult to determine what the natural life span of various cultivars would be in the absence of the pathogen. What follows are the top-rated coneflowers for the mid-Atlantic from a horticultural and ecological perspective based on the center’s evaluation.

Echinacea ‘Sensation Pink’

A product of the breeding efforts of Marco van Noort in the Netherlands, Echinacea ‘Sensation Pink’ produced one of the most vibrant displays in our trial. Intense, neon-pink flowers are held on dark stems that further accentuate their otherworldly floral color. In contrast to the exuberant blooms, ‘Sensation Pink’ manifests a restrained and more compact habit relative to its wild counterparts. While ‘Sensation Pink’ is undoubtedly a horticultural standout, it proved to have substantial ecological value as well. In fact, this cultivar was one of the five most pollinator-visited Echinacea in the trial. This is one truly sensational plant.

Echinacea ‘Santa Fe’

Echinacea ‘Santa Fe’ is a seed-produced cultivar from the Proven Winners^® LAKOTA™ Series of coneflowers.

Despite some expected variation in seed strains, Echinacea ‘Santa Fe’ showed remarkable consistency in our trial and was similar in many ways to Echinacea ‘Balsomcor’ (SOMBRERO^® Hot Coral), although ‘Santa Fe’ was decidedly more vigorous. This tidy and well branched plant reaches 2 feet tall and wide at maturity. Striking coral-red flowers are produced en masse from late June through late July before eventually fading to attractive shades of pastel pink. Echinacea ‘Santa Fe’ not only scored as a top performer in the trial, but it was also popular with trial garden visitors who voted it among their top five favorites in both 2018 and 2019.

Echinacea ‘TNECHKR’ (KISMET^® Raspberry)

Echinacea ‘TNECHKR’, also known by the trade name KISMET^® Raspberry, is one of several Terra Nova Nurseries introductions that were evaluated in this trial. KISMET^® Raspberry was a standout in the trial thanks to its strong vigor, saturated color, and oversized blooms. The glowing raspberry-pink petals are at their peak in early July and, while comparable to the blooms of Echinacea ‘Sensation Pink’ and Echinacea ‘Purple Emperor’, KISMET^® Raspberry maintains the slightest floral edge over these close competitors because of the sheer vibrancy of its blooms. KISMET^® Raspberry hybrid coneflower has an attractive and consistent 3-foot-by-3-foot habit, similar to that of E. purpurea ‘Pica Bella’.

Echinacea ‘Snow Cone’

Echinacea ‘Snow Cone’ is an outstanding cultivar introduced by Intrinsic Perennial Gardens in Haebron, Illinois. This pocket-sized hybrid is one of the most compact coneflowers in our trial. Fully grown, it reaches 2 ½ feet in height and width, making it a perfect choice for container gardens or the front of a border. Despite its modest size, ‘Snow Cone’ puts on a first-class floral display from the middle of June through late July.

During peak bloom, this cultivar’s foliage is almost completely obscured by a profusion of 3-inch snowy white blossoms. In addition to a standout floral display, ‘Snow Cone’ is reputed to be a long-lived plant, a trait associated with its E. tennesseensis parentage.

Echinacea ‘Purple Emperor’

Echinacea ‘Purple Emperor’ is one of three members of the Butterfly™ Series from AB-Cultivars that excelled in the trial. This particular cultivar is named after a species of Apatura butterfly that is native to Europe and Asia. ‘Purple Emperor’ hybrid coneflower distinguishes itself from other medium sized cultivars thanks to its vigorous and uniform growth and its large 4 ½-inch flowers produced in late June though early July.

An interesting feature of ‘Purple Emperor’ is the slightly reflexed, two-toned petals that are dark pink at the cone and fade to a lighter pink toward the outer edges of the flowers.

Echinacea purpurea ‘Fragrant Angel’

A Terra Nova introduction, E. purpurea ‘Fragrant Angel’ was the highest rated white flowering cultivar during our first coneflower trial and it remains impressive more than a decade later. The large, pleasantly fragrant, 4 ½-inch flowers present their porcelain-white petals to great effect from early July into August. Other white cultivars such as E. purpurea ‘Baby Swan White’ and E. purpurea ‘Happy Star’ have slightly reflexed petals, but ‘Fragrant Angel’ has horizontal petals that contribute to its more substantial appearance. In addition to these notable horticultural qualities, ‘Fragrant Angel’ is also popular with bees, wasps, and butterflies. In fact, this cultivar averaged the most pollinator visits, including the most butterfly visits of any coneflower in our trial between 2018 and 2019.

Echinacea ‘POST301’

Echinacea ‘POST301’ (Postman) is a member of the Butterfly™ Series from Arie Blom of AB-Cultivars in the Netherlands. Each cultivar in this series is named for a different butterfly, in this case the Mexican and Central American postman butterfly (Heliconius sp.). This coneflower is known for its large, intensely colorful flowers and prominent dark cones. Beginning in June, showy oversized buds with attractive dark centers are held well above the foliage, a feature that greatly expands its season of interest. The buds are then followed by 4½-inch marigold-yellow flowers that transition to crimson-red in early July and eventually fade to shades of watermelon pink later in the month. The sheer size and quantity of blooms can cause some flopping later in the season, although timely deadheading can counteract this tendency.

Echinacea ‘Julia’

The flowers of Echinacea ‘Julia’ are particularly noteworthy and share similar orange tones to the South American Julia butterfly for which it is named. The petals of ‘Julia’ showcase the same two-tone quality that SOMBRERO^® Hot Coral displays in the early season but on a larger flower. As the petals mature, they begin to express an attractive bicolor effect. The petals are a deep rosy-pink closest to the cone and vibrant tangerine at their tips. Near the end of the five-week bloom period in mid-July the flowers trade their vibrancy for soft pastels in a manner similar to Echinacea ‘POST301’ (Postman).

Echinacea ‘TNECHKIO’ (KISMET^® Intense Orange)

From Terra Nova’s KISMET^® Series, Echinacea KISMET^® Intense Orange features the same breeding strategies as Echinacea KISMET^® Raspberry and is similarly advertised to have increased numbers of flowers and greater garden adaptability. This coneflower was often compared to Echinacea ‘Santa Fe’ and Echinacea ‘Balsomcor’ (SOMBRERO^® Hot Coral) due to similarities in habit and flower color and, like ‘Santa Fe’, it was also voted a top five favorite by visitors. KISMET^® Intense Orange coneflower produced some of the most saturated red-orange flowers in our trial that eventually faded to handsome apricot tones in late summer.

Editor’s note: Information published by permission from the Mt. Cuba Center Echinacea report.

For more: Read the trial report in its entirety at mtcubacenter.org/trialgarden. It includes scoring for all plants, honorable mentions, pest and disease issues, cultivation tips, and pollinator-preferred plants.