In Flanders Fields, where ornamental trees and plants grow – Episode 1

The Aragon Bridge in Lier (Photo courtesy: Lier Tourist Board).

The Flanders’ Agricultural Marketing Board (VLAM) invited FCI to see a cross-section of ornamental horticulture in the province of Antwerp and the Kempen, aka Campine. Episode one takes us to Buxus king Herplant from Beerse and succulent grower Belgicactus in Westerlo.

The self-governing Flanders Region includes the provinces of Antwerp, East Flanders, Limburg, Flemish Brabant, and West Flanders. Ornamental horticulture geographically concentrates in East Flanders, with Wetteren and Lochristie being epicentres of nursery stock and flowering pot plant production, respectively.

In the province of Antwerp, nursery stock and potted plant growers are much more scattered. So, the tiny town of Lier, 20km east of Antwerp, is a great location to explore seven of the region’s leading companies – because departing from Lier’s city centre, they are all within a 50km radius.

Lier, at the confluence of the rivers Grote and Kleine Nete, attracts tourists and sightseers keen to see its Brabant/Rococo townhall and adjacent UNESCO World Heritage Belfort, plus its iconic Zimmer Tower named after clockmaker Zimmer, who presented his native town with a Jubilee Clock in 1930 when Belgium celebrated its Centenary. For the sportier types, Lier also hosts the ‘Abarth Works Museum’, the place to be regarding Abarth sports cars, spare parts and genuine Abarth engines.

The famed French poet and novelist Victor Hugo visited Lier by stagecoach in 1837 and marvelled at the city’s beauty. On a much less romantic note, Lier is engraved in Belgium’s national memory as the scene of a car accident that killed the then extremely popular singer Louis Neefs and his wife in 1980.

Lier is known as ‘the gateway to the Kempen’, aka the Campine, a cross-border area that extends across the frontiers of Belgium and the Netherlands. Campine is a hybrid form of the Latin word Campinia, meaning open field. In the late Roman era, people also named the land Taxandria, a homage to the then omnipresent Taxus (yew) growing naturally in the wild. Some historians sustain that the Campine’s wild Taxus died out because people in the Middle Ages discovered that the tree makes good crossbows and bolts, leading to a massive uprooting of trees.

Left to right, son and father Alec and Didier Hermans.

Herplant

Today, brothers Didier, Luc and Louis Hermans ‘domesticate’ Taxus and Buxus trees using selective breeding to create more disease and pest-resistant, visually appealing, scientifically tested, and well-rooted varieties.

Working in nursery stock is in the Hermans’ genes. Their grandparents earned a living as professional tree trimmers while their parents owned a modest conifer nursery.

Considering the lousy patch the Boxwood (aka Box or Buxus) in particular has gone through over the past two decades, their company Herplant, which started in 1985, deserves credit for perseverance in turning adversity into an opportunity.

The adversity began in the 1990s with the arrival of the invasive fungus box blight (Cylindrocladium buxicola, syn. Calonectria pseudonaviculata). It worsened when the first box tree caterpillar (Cydalima perspectalis) emerged in the Netherlands and Germany in 2006. Since then, Box Blight and Box Tree Moth continue to damage, causing debilitating defoliation and decimating ornamental and wild boxwoods.

A purpose-built greenhouse at Herplant’s headquarters in Beerse hosts lush-looking BetterBuxus mother-stock.

BetterBuxus

To turn the tide, Herplant joined forces with the Flemish Institute for Agricultural and Fisheries Research (ILVO) in 2007 in a breeding programme with slow-germinating Boxwood seed. The need for simultaneously available flowers to crossbreed is two of the most significant challenges.

Their work resulted in BetterBuxus, the industry’s first-ever collection of scientifically bred blight-resistant boxwood. The brand name (in the USA, aka Better Boxwood) comprises four varieties. BetterBuxus ‘Heritage’ is similar to the standard Buxus sempervirens, though a little more compact. However, Didier Hermans quickly adds that BetterBuxus and Buxus sempervirens originate from different genetics and are worlds apart. He says, “It is important to recognise that the genus Buxus comprises more than 100 species, most growing in tropical regions.”

‘Rennaissance’ is a low-growing, small-leaved variety suitable for low-box pattern designs and only needs clipping once a year. The fastest growing is ‘Skylight’; its vigour makes it well-suited to topiary and tall, cloud-pruned hedges. ‘Babylon Beauty’ has a low, spreading habit useful for large ground-cover sheets. Meanwhile, trials involving a fifth sibling within the BetterBuxus family is a work in progress at the gardens of Het Loo Palace in the Netherlands.

Herplant sells well-rooted potted Buxus plants all year round, even when temperatures are scorching hot.

Propagation

A purpose-built greenhouse at Herplant’s headquarters in Beerse hosts lush-looking BetterBuxus mother stock. Lighting and soil heating enable a harvest frequency of six annually, yielding 120,000 cuttings annually.

Experienced plant propagator and Buxus grower De Vos-Hertschap from Lokeren, with whom Didier has forged many years of friendship, places cuttings into a moistened sandy medium using 104-hole, 84-hole or 60-hole trays.

Depending on the season, the roots develop within an average of two months, in midsummer two weeks earlier. Once the plug plant’s roots have extended in all directions, they are hardened off and repotted into P10.5 (landscaping) or P13 (garden centre customers). Then, these semi-finished plants return to Herplant, where they grow into saleable plants.

De Vos-Hertschap and Herplant place two cuttings per pot, and Herplant take pride in giving plants the right amount of space in the container field, allowing them to grow into beefy and resilient specimens.

This growing method is in contrast to the common practice of uprooting Buxus sempervirens with a special machine that lifts plants with the soil and the immediate root system. These cut-off Buxus rootballs are subsequently placed into a bigger pot, with sales of these ‘pot-pressed’ items frequently modelling on tailormade DIY or discounter orders. Didier notes, “The problem with ‘pot-pressed’ is that when hot weather arrives, you’ll have to put uprooting on hold temporarily. In contrast, how we do it allows us to sell well-rooted plants all year round, even when temperatures are scorching hot.”

In Taxus, Herplant propagates mostly in-house with additional one-year-old seedlings purchased in Zundert, the nearby epicentre of nursery stock production in the Netherlands.

Beautifully designed Buxus garden at Herplant’s headquarters in Beerse.

Taxus

Taxus is finished in P 10.5, 1.5, 5, and 12-litre pots with bigger rootballed plants grown in the field. Taxus specimens such as low-growing and compact Taxus baccata ‘Tiny T’, a KVBC silver medal winner at last year’s GrootGroenPlus show, Taxus media ‘Eleganza’ with male flowers only (no berries) and fine dark green needles plus the curlier and long-needled Taxus baccata ‘Exotica’ are primarily rooted in-house.

There is no single best alternative back to Buxus, which used to be a prominent horticultural crop globally but has lost its stable ranking, says Didier, quoting 2017 figures sourced from Royal FloraHolland. He elaborates, “The Netherlands are the leading European country for Buxus, producing more than 17 million of the European total of 43 million plants.”

The 2022 figures provided by market analyst Agrimatie indicate that production areas dropped from 1,684ha in the 2011 heydays of Buxus to 612ha in 2022. This decrease in area was accompanied by a decline in the number of growers, from approximately 900 in 2013 to 100 in 2022.

It is safe to say that box blight has tested the resolve and the finances of boxwood growers worldwide, with price cuts hammering this sub-sector of nursery stock.

Yet, despite his frustration at the media’s frequently unbalanced coverage Boxwood received, Didier Hermans always kept his belief in Boxwood intact. He is adamant this is how he and his brothers want to make their living. He says, “Considering the many suggestions for replacements of Boxwood in landscapes and gardens, nothing brings a sense of formality, reliability, and low maintenance to a garden like a Boxwood.

There is no single best alternative. Herplant was one of the partners in a 2015 Ilex crenata project, heralding two PBR-protected and cuttings-raised Ilex crenata cultivars as the perfect alternative to Boxwood hedging. Gardeners planted them in historic gardens such as Paleis Het Loo in the Netherlands and Vaux-le-Vicomte in France but soon afterwards had to uproot many of them. Ilex crenata is not the best solution, as it has larger leaves than the boxwood and does not provide quite the compactness of form. Also, it turned out to be very picky regarding soils, preferring sandy soil with low pH.”

Didier thinks the market entry of BetterBuxus marks a watershed moment. It will lead to a renewed interest in Boxwood, focusing on the good – year-round colour and structure to the garden and hassle-free clipping – instead of the bad. He notes, “Today, Buxus sempervirens make up 90 per cent of the market. I hope that more tolerant varieties and, naturally, our resistant varieties gain market share. Boxwood is and will remain indispensable for growing a small, ball-shaped plant for the retail market quickly and profitably. Other evergreens will not give the same result. Today, demand for Buxus tends to exceed the offer, particularly regarding the bigger pot sizes. So, for the near future, I anticipate an increase in production area again.”

It is safe to say that the first is the most severe between Box Blight and Boxwood Moth. While BetterBuxus offers a solution to the fungus, the moth still wreaks havoc. Didier explains, “The moth is here to stay, but if you treat your buxus twice a year at the right moment, the pest is easy to treat biologically and chemically. Products based on Bacillus thuringiensis (not admitted for the hobby market in Belgium, the Netherlands, and the UK) are very effective in combating young caterpillars. If this is not too much to ask from the gardener? We increasingly strive to make our planet greener and rally to save the Amazon while neglecting our gardens. If the moth is invasive, we should not allow it to spiral out of control; we must act now. A genus that originates from the Late Cretaceous epoch and has been growing for 74 million years must have something going for it, mustn’t it?”

Today, as its name aptly evokes, Sempervivums are here to stay with a 45-50 per cent volume market share within Belgicactus’ business operations.

Belgicactus

These days, the business name Belgicactus is a red herring, although it started as a cacti nursery in a 1,000m2 plot adjacent to Jozef Gielis’ home in 1985.

The company’s 28,000m² plant nursery currently resides in Westerlo and grows only succulents. Apart from its standalone line of Opuntia humifosa, aka prickly pear, which technically belongs to the Cactaceae family, there are no prickles in sight.

“Growing cacti and keeping them pest and disease-free can be a daunting task while supply constraints in starter plants also played a part in our 2014 decision to focus on specialisation and stopping cacti production altogether,” explains second-generation Jef Gielis, who, with his brother Jan oversees the day-to-day operations of the company that grows approximately 60 varieties of Sempervivum for outdoors in pot sizes ranging between 5.5 and 23cm. Echeveria, Crassula, Sedum and Aeonium are sold as indoor plants in pot sizes 5.5 to 13 cm.

In a year, Belgicactus produces between 2.5 to 3.5 million plants sold to predominantly exporters and cash and carry stores in the Netherlands and Belgium.

Jef Gielis, of Belgicactus.

Customer base

Jef says the days when Westerlo-grown succulents sold through the Dutch auction clock are long gone. “Apart from Euroveiling in Brussels, no plants are auctioned off. At the large Dutch auctions, the risk is the products get snowed under, not receiving the attention and price the quality product deserves.”

Markets with strong succulent demand include Germany, the UK, Austria, Switzerland, Italy, and Denmark.

Traditional wholesalers make up most of their customers abroad. Retail is not a market segment because it would find it challenging to supply on the mass scale needed to fill retail shelves.

Jef elaborates, “Also, we feel that retail is not per se interested in bringing variety to their shelves while our motto is to offer less conventional succulents in a rainbow of colours and shapes and being a one-stop shop.”

Sempervivum

1995 marked a watershed moment in the company’s history when it added the first Sempervivums to its portfolio. Today, as its name aptly evokes, Sempervivums are here to stay with a 45-50 per cent volume market share within Belgicactus’ business operations.

Sempervivums propagate by offsets. In June and July, part of the 12 full-time staff take to the 18,000m2 lava growing beds outside to harvest cuttings and subsequently place these in 3.5cm plugs.
In the spring of the following year, these starter plants are potted in different pot sizes, with the first plants ready for shipment by the summer of the same year.

But lines can be blurred as some plug plants are only potted one year later. Practices in potting have limited flexibility as Sempervivum plants begin to flower after two to three growing seasons. Jef explains, “Foliage is the main attraction in commercial Sempervivum production. So, all Sempervivums are shipped before reaching their flowering stage because, without flower stalks, more plants fit on a Danish trolley. At the consumer level, flowers add interest to the plant. After flowering, the central rosette dies, leaving many mini plants behind to replace it, and that’s an exciting process to witness.”

Colorockz

Belgicactus puts significant marketing muscle behind its range of Sempervivum. All in-house bred Sempervivums sell under the Colorrockz brand, with plant propagators and rooting stations in Europe, the USA and Australia being granted a licence to reproduce.

Today, Colorockz comprises seven varieties, all of which the company says feature remarkable colours, a well-developed root system, vigorous growth, disease and pest resistance and plant hardiness.
In 2022, judges at Belgium’s horticultural trade show Florall crowned Sempervivum arachnoideum Colorockz ‘Coconut Crystal’ with the Gold Trophy. Buyers looking for the purest white in Sempervivum should check Sempervivum Colorockz ‘Arctic White’. Radiant as it is, you need sunglasses on in the container field to protect your eyes.

A 10,000m² greenhouse space hosts the company’s indoor cultivation of a range of Aeonium, Aloe, Echeveria, Crassula and Sedum, crops which are ‘cold finished’ in winter.

A 10,000m2, retractable greenhouse hosts the company’s indoor cultivation of Aeonium, Aloe, Echeveria, Crassula and Sedum, crops which are ‘cold finished’ in winter.

Sustainability

Jef explains, “One of our sustainability goals is to reduce our dependence on fossil fuels. So, we turn down the thermostat to a minimum of six degrees in winter. When growing our plants, we try to follow the natural rhythms of nature. Hardening off younger plants is done inside our retractable greenhouses.”

The MPS-certified company minimises its environmental footprint with measures including harvesting rainwater run-off, using organic-based biostimulants rather than traditional chemicals, an IPM programme, 70 per cent peat reduction and fully recyclable pots.

“We take pride in growing the best cold hardy Sempervivums and greenhouse-grown succulents, 100 and 50 per cent fungicides-free respectively. Also, we have made strides with biological control agents.

“One of the most common and dreaded pests is the fungus gnat, aka sciarid fly. Its larvae feed on succulent stems and roots, causing the plants to wilt and die in a worst-case scenario. To fight it, we successfully use parasitic nematodes or the Steinernema system, small worms that conquer the fungus gnat larvae, releasing symbiotic bacteria that quickly kill them.”

Innovation

Jef concludes by saying that innovation is key. Particularly strong selling is the succulent planters, designed to fit any space or lifestyle and backed by a Fabulous Fat Friends campaign. Creating a buzz also is Chelsea-award-winning Semponium, a cross between Sempervivum and an Aeonium, developed at Surreal Succulents in the UK.

Jef notes, “They have received great interest because they were bred for hardiness, taking -2°C outside. However, we believe their hardiness is debatable, so we opted for Semponium ‘Destiny’, ‘Sienna’ and ‘Green Diamond’ because we think they are most cold resistant.”

Not new and royalty-free on the market for many years, but therefore no less beautiful is Kalanchoe pumila, an artisan succulent featuring purple-greyish, fleshy leaves with a white powdery covering. Turnover-wise, it is not among the top-selling products, with pumila sales predominantly happening in spring and autumn.

Those with long enough memories in the Netherlands, Belgium, Italy and Spain — the epicentres of European succulent production — would probably remember a period for the succulent plant market, most notably in the 1970s and 1980s, representing something of a golden age.

Future market dynamics

When reflecting on future market dynamics, Jef reckons it is happening again with massive expansion in succulent production and trading during the Covid years. “The industry saw the first signs of oversupply over the late summer of 2022. I believe that to future-proof your business, it is vital to stay focused on innovation. Over a decade ago, we began breeding Echeverias and Sempervivum in-house, with spectacular varieties such as ‘Coral Red’ being the blooming result. Customers always ask for something new, so you must strengthen your product innovation capability. At the same time, pursuing sustainability is an example of process innovation that focuses on the innovation of skills, facilities and cultivation practices that reduce the use of peat, energy, and crop protection products.”

This article was first published in the October 2023 edition of FloraCulture International.