This summer, hardy vegetable varieties had the chance to shine. "Lettuce is very popular when it's extremely hot, so that's exactly when you have to have it," begin Bert Hendrikse and Fokke Hoeksma, Enza Zaden representatives.
Bert Hendrikse and Fokke Hoeksma both represent Enza Zaden.
This Dutch company's Summer Field Days were all about new varieties. Still, the men were quick to proudly mention the Eduardo. "This variety has proven itself for years and again this year. Iceberg lettuce is increasingly sold cut, and then the head's paramount. Eduardo has very nice layers, deals well with inner edges, and has a small stem; that's what processors like to see."
Iceberg lettuce with good internal quality.
Mercelo is a new Enza Zaden iceberg lettuce variety. It is just as robust and high-quality as Eduardo but, then, in the spring. "The approval for the use of successful aphid controlling substances expires in 2025 at the latest. Growers are, thus, looking for more robust, resistant varieties. We also help them understand more about the importance of good soil quality," say the men.
Most endive is sold processed. The Keilure variety has been developed for the very earliest cultivation (planting in weeks 9 -13). "It's a very vigorous variety that withstands the cold very well. Cold is a problem, especially in spring," explains Bert.
Keilure in the demo field.
You can grow leeks all year round in open fields. The new hybrid variety Oslo is suitable for autumn cultivation through to regrowth and is characterized by its high cleaned yield. Bert: "Oslo does very well. It has a high production of uniform, solid, easy-to-peel shafts."
"Also, Oslo F1 is very thrip-resistant - which makes a difference, especially this season -, leaf spots and rust. Besides high production, it offers growers more security now that they're allowed to use fewer agents against these diseases."
Oceanique is a newcomer in the fall cauliflower segment. It can be harvested earlier than other varieties.
Oceanique head sheathed in green leaves.
“These cauliflowers are smooth, firm, beautifully white, and weighty," adds Fokke. "Plus, they're uniformly high-quality. Oceanique copes well with wetness and has a strong underside, so its leaves stay green."
"The heads are sheathed in nice green leaves, which looks great when they're in the boxes. Another strong point of the variety is that it scores well technically: it's easy to harvest and wraps itself well. Oceanique is quick to harvest too."
Oceanique's healthy underside.
Enza Zaden has recently focused strongly on developing highly downy mildew-resistant spinach varieties. That includes two types for spring and fall cultivation: Longhorn and Traverse. "Traverse is fast-growing with strong, erect leaves. Longhorn has oval, round, thick leaves," Bert concludes.
Longhorn spinach in the demo field.
Enza Zaden opened its demo field in Twisk and its subsidiary, Vitalis Biologische Zaden's field in Voorst, to the public. This Summer Fields Day was the first to also feature its hydroponic greenhouse in Enkhuizen. All three of these sites are in the Netherlands.
Fokke and Bert inspect the demo fields.
Little gem in the Twisk demo field.
Hydroponic cultivation in Enza Zaden's greenhouse at its head office.
Hydroponic cultivation is where crops are grown on water rather than in full soil. Hydroponically cultivated lettuce can be grown very sustainability and cleanly, and can be offered in an extremely high quality year-round.
Vitalis Biologische Zaden's organic leafy vegetables' demo field in Voorst.
Coen ter Berg, agricultural advisor, in the profile trench between Vitalis Organic Seeds' strip cropping fields. Strip cropping involves growing several crops, side by side, on a plot. The diversity of crops means there are all kinds of above- and below-ground interactions between the crops, which ensure the optimal use of nutrients, water, and sunlight. The profile trench is a cross-section of soil you can walk in, and inspect the plants' roots.