Dutch seed Open Days - Widening the field

The annual vegetable days in the Netherlands have revealed a range of new varieties from diverse portfolios, Richard Crowhurst finds.

Red shallot Camelot - image: HW
Red shallot Camelot - image: HW

The annual vegetable open days in the Netherlands continue to attract visitors from around the world, with a number of UK growers and retailers travelling to sites in the north-west of the country. While some companies continue to focus heavily on brassica crops at the events, many others are keen to show the diversity of their portfolio. For the first year, Bejo Zaden even had a display of glasshouse crops including tomatoes and cucumbers, while Syngenta demonstrated how well-adapted many of its varieties were to hydroponic production.

Bejo Zaden

Despite this, it was some of the more traditional crops that were attracting the attention of British visitors to Bejo's headquarters at Warmenhuizen. The new red shallot Camelot has a good-quality skin and is high-yielding, while the attractive colour is described by Keely Watson of Bejo's UK agent Elsoms as a marked improvement on the colour of Prisma.

Radicchio is a growing range for the company, and while Watson says Leonardo is "still a really popular variety for us", newcomers Rossini (Bejo 2708) and Rubro (Bejo 2710) are both suitable for UK production. Rossini has the potential to extend the cropping season into late autumn or early winter, while Rubro, which proved itself in the harsh 2010-11 winter season, is hardy enough to be harvested into late February. The use of humidity-controlled cold storage could further increase the marketing period for Rossini.

While Nairobi continues to dominate the UK pre-packed carrot market, Bejo is making progress with newer varieties. One of these is the early Nantes type Nominator F1, which has smooth, well-filled cylindrical roots at around 96 days maturity. For specialist growers, the new Chantenay type Caracas F1 produces small conical and well-filled miniature carrots. With a similar maturity to Newcastle, it is ideal for high-density production.

One new crop that Bejo is having considerable success in is asparagus and Elsoms has identified Cumulus F1 as being particularly suitable for early UK production. Although used as a white variety on the continent, it is also well suited to green production and "does not seem to need as many heat units to initiate bud formation", says Watson. For best results, the company recommends a planting density of six crowns per metre.


A couple of kilometres up the road from Warmenhuizen lies the trial site of Nickerson-Zwaan and Clause. Both companies were apologetic that the extremely wet summer had delayed planting this year, with some plots not reaching maturity and others suffering from waterlogging.

On the whole, brassicas had survived well, in particular the new Brussels sprout NiZ 16-493 F1, which senior range manager Nick Bolton describes as "the best sprout so far from the Nickerson-Zwaan sprout programme". A very late variety, it will crop in April in Scotland, allowing British retailers to maximise the UK season. With good frost resistance, it is undergoing commercial trials this year with a view to becoming available commercially in 2013.

On carrots, Nickerson-Zwaan is trying to combine the strengths of Eskimo with earlier maturity, says range manager John De Soyza. The first result of this is Attilo F1 (formerly Vac 55), an early-bulking maincrop variety with good strength and tolerance to cavity spot. "It has an intermediate level of frost resistance, while yield analysis has shown it to produce both high gross yields and a high percentage of marketable product," says De Soyza. "It's comparable with the standard industry variety and has done well in Scotland this year."

Another crop the breeder has focused on recently is leeks. "It's been a roller coaster, but we now have stability in the programme," says De Soyza of the new introduction Callahan F1. Bred for the November-to-February period, it coped well with last winter's severe conditions in field storage and has proved popular thanks to its ease of harvest and field peeling ability. "We've had some very favourable feedback from growers," he adds.


Clause, like its sister company Nickerson-Zwaan, had also suffered from the weather, with its courgette plots being particularly affected. However, marketing manager John Ward feels that the new introduction Adriana F1 (CLX 29125) could be a hit with UK growers thanks to its high levels of virus tolerance and its good yields of uniform dark-green fruit.

Ward concedes that efforts to introduce deeper-coloured roots to the carrot market have proved unsuccessful, meaning that late-season introduction Match F1 "has the same colour as the market thinks a carrot should be", he says. With a smooth root and the ability to produce crops in excess of 100t/ha, it is ideal for late top-lifting. It also performs well under straw, with less Sclerotinia, helping the smooth long roots to keep well until April or even May in Scotland.

Despite the current economic climate, sales of bagged salad products continue to be strong, so the frisee-type endive Emily, which has a high yield for processing, has attracted plenty of interest. "The frisee market has moved from very fine to coarse types," Ward explains. "Growers need better control of tip burn and better head weights."

With the potential to produce heads weighing 850g-1kg, compared with industry budgets of 600g, Emily has performed well with growers, and Ward says they are keen to grow more next season. "The better fill in the middle of the head helps with the self-blanching," he adds.


From its strong background in conventional broccoli, Seminis has been working to introduce a long-stalked variety that can be harvested mechanically. The concept was first introduced to growers from the UK and Ireland in Lincolnshire five years ago, but it was at this year's open day at Monsanto's Enkhuizen facility that the company confirmed that Seminis Easy Harvest varieties would be commercially available in 2013.

In the trial field, two varieties were on display - Easy Harvest RX 0598 0021 and RX 0590 0099 - although it is 0021 that the company is focusing on for maximising production from a single harvesting pass thanks to its raised head, which also allows for machine harvesting.

Also in broccoli is the new variety Beneforte (RX 0599 1199), which has been bred to give high levels of the plant chemical glucoraphanin, which is claimed to have health benefits. From an agronomic point of view, the head is well domed and has excellent shelf life.

In the salad segment, the company was displaying a range of new products, including spinach (RX 0666 1505), Batavia, Butterhead, Romaine (RS 0464 0500), Oakleaf (RX 1689 6680) and Iceberg (RX 0648 3732 and RX 0648 3758) types.

Rijk Zwaan

In contrast to the other north Netherlands trial sites, Rijk Zwaan's field outside the village of Opperdoes contains only brassicas, with the company showing off the rest of its crop range further south at Fijnaart. As well as giving the company a format to display its latest brassica varieties, this year it allowed it to display the results of a number of trials investigating factors such as planting rate and fertiliser regime.

Named just in time for the open days is the new green cauliflower Gilverde (26-826 RZ), which crop specialist John Buijsman describes as "similar to Vitaverde, but with a stronger green colour". Although very uniform, it is only really suitable for autumn production.

"You could overwinter it, but it won't go through the summer," he adds. Along with Formosa - which is now commercially available - and 26-851 RZ (Mazzaverde), it is resistant to both ring spot and white blister.

Two new white cabbages, 30-277 RZ and 30-263 RZ have potential for processing and coleslaw production. Of 30-277, Buijsman says: "It has a very white internal structure and should be interesting for coleslaw, but it will be another one or two years before it is available commercially." By contrast, 30-263 has a greener internal colour giving it the potential to be used for dehydrated products.


Like Seminis, Syngenta is also developing varieties of broccoli that are easy to harvest, although it is focusing on increasing the amount of product that can be obtained from a single pass by a harvesting gang rather than by machinery.

The first variety to come from this targeted breeding approach is SGD40352R. "It is so uniform at maturity that you get a high percentage of plants that are mature at the same number of days," explains Syngenta crop specialist Mike Molyneux.

Multiple plantings in the UK should enable growers to produce crops in spring and summer, and as much as 60 per cent should be cut on the first harvest. Large-scale field trials will be conducted in 2012, but Molyneux describes it as "the stand-out variety of our broccoli trials this year".

Syngenta has a strong squash portfolio, as was evidenced by the wide range of varieties on display at this year's site. As well as more familiar green varieties, such as Milos, which has been one of the best-performing varieties in this year's National Institute of Agricultural Botany trials, there was the striking yellow variety Golden Delight, which has been sold at retail in the UK this year and has resistance to ZYMV and YMV viruses.

There is also the distinctive round squash Brice. "We're seeing a much greater demand for more diversity in courgettes," says crop specialist Chris Lees. "We've got another yellow variety for UK trials this year. In Italy they eat a wider variety of courgettes and it's an exciting segment - there's a lot more to come."

The company has also been busy developing leafy salads. Brillantes is a new escarole-type endive that has been grown in France for a couple of years and has shown good performance against tip burn and bolting in UK conditions, while the Bellagio multi-leaf one-cut range continues to evolve with new varieties and leaf shapes.

Lees adds: "Friscaro is as close as you'll get to a multi-leaf escarole and has produced good feedback from growers and processors." And while Robino has been popular in red-leaved varieties, Syngenta is bringing forward new reds with full Bl 1-28 resistance. The first of these to be commercially available is Rodagio (LS9429), which with its red and green leaves retains the Bellagio concept of even leaf production and avoids further cutting.

Novelty and traditional cauliflowers compete

Brassicas are still a mainstay of Dutch breeding, but the introduction of coloured cauliflower packs into a major UK retailer by TH Clements has reignited interest in novel varieties.

The current pack uses the yellow Ortoli and purple Graffeti, as well as a new pink type, all bred by Syngenta. "The vegetable needs modernising and this provides a modern take," explains Syngenta crop specialist Mike Molyneux. Despite this, the company is also breeding more white types.

Nickerson-Zwaan's new white cauliflower EB3103 F1 comes from Vilmorin's breeding programme. "In the early summer period it's difficult to get a dense enough curd, but this stood out in trials two year ago," says senior range manager Nick Bolton. It performs well under polythene and successful field trials this year should see it launched at the end of 2012.

Seminis had a strong range of cauliflower on display, all of which were for traditional markets. Seminis technical development manager Kevin Walsh says new variety RS 0597 5781 has "good size and good weight" and does well in poorer soil conditions, too.

Bejo Zaden displayed Romanesco-type Veronica, but as Keely Watson from UK agent Elsoms points out, it is difficult for growers to pack it without causing damage.

Besides a wide range of true Romanesco varieties, Rijk Zwaan was also trialling green cauliflowers. As well as established Puntaverde, Vitaverde and Formosa, the new green cauliflower Gilverde (RZ 26-826) has been joined in trials by new Romanesco Mazzaverde (RZ 26-851).

Have you registered with us yet?

Register now to enjoy more articles and free email bulletins

Sign up now
Already registered?
Sign in

Read These Next

What should growers make of the Government's migration report?

What should growers make of the Government's migration report?

By holding out the "possibility" of a seasonal agricultural workers scheme (SAWS), the Migration Advisory Committee's (MAC) long-awaited final report, published this week, makes an exception for fresh produce amid its wider call for a shift away from low-skill immigration.

Tractors: market roundup

Tractors: market roundup

Manufacturers are working to provide solutions to many challenges. Sally Drury looks at their newest models.

What does the Agriculture Bill mean for growers?

What does the Agriculture Bill mean for growers?

The publication of the Agriculture Bill this week formally kick-starts the Government's plans to implement a "green Brexit" for farming, the area of the economy most impacted by the UK's withdrawal from the EU from next March.

Follow us on:
  • Facebook
  • LinkedIn
  • Twitter
  • Google +

Horticulture Week Top UK FRUIT PRODUCERS

See our exclusive RANKING of UK Fruit Producers by annual turnover plus the FULL REPORT AND ANALYSIS.

Horticulture Jobs
More Horticulture Jobs

Pest & Disease Tracker bulletin 

The latest pest and disease alerts, how to treat them, plus EAMU updates, sent direct to your inbox.

Sign up here

Professor Geoffrey Dixon

GreenGene International chair Geoff Dixon on the business of fresh produce production

Read Professor Geoffrey Dixon