How are onion growers, contract workers and consultants responding to climate change? We asked four guys named Peter in the Netherlands and Belgium. The growing season is increasingly characterized by extreme conditions, they’ve noticed. Fertile soil, compost, manuring, proper variety choice and crop-specific measures are becoming increasingly vital for cultivating resilient onions. 

Peter van Rossum 
Working foreman, Maatschap Van Nieuwenhuijzen, Melissant, the Netherlands 

Peter van Rossum is working foreman at Maatschap Van Nieuwenhuijzen in the Dutch village of Melissant. For five years he’s been in charge of managing all the farm’s arable crops, including a seed onion field every year. After a few years of growing Hytech, they’re now harvesting Hyway. 

The Dutch growing season is increasingly marked by extreme weather conditions, Van Rossum says. “In the past few years, we’ve seen longer and longer periods of excess rainfall and flooding, along with emergence problems and growth delays. We’re using compost, growing green manures, applying animal manure and using min-till and no-till cultivation to try to increase the organic matter content of our soil and level out moisture surpluses and deficits.” 

The farm has surface water available for irrigation, helping the growers to combat moisture deficits. This enables them to achieve more or less acceptable kilo yields, Van Rossum says. “But in the future, we want to invest in controlled drainage to cope with rainfall deficits more efficiently, although it remains challenging in onions. Fortunately, it can be a cost-effective investment for multiple crops. 

We could also go for an irrigation/fertigation system,” he adds. “But it comes with a higher average price per kilo. As a grower, with the weather, you just never know.” 

Peter van Hauwaert 
Contract worker, Meulebeke, Belgium 

Contract worker Peter van Hauwaert has noticed more problems with onion emergence in recent years. Belgium’s increasingly harsh northeasterly winds mean the ground has a hard time warming up in spring and the topsoil dries out quickly, he says. “So, if you irrigate you get soil crusting of course. That’s been causing a lot of problems in the past few years. Pre-germinated seeds can help with this.” 

Van Hauwaert hasn’t yet used a drip system, but he knows irrigation adds a lot of value in terms of making cultivation profitable. “And it also ensures customers get a better, more stable product.” 

As a contract worker, he doesn’t make decisions about variety choice. But one thing he’s sure of is that growing onions without regular customers and selling off-farm is “very financially risky”. 

Peter Ickenroth 
Crop consultant, Agrea, the Netherlands 

Peter Ickenroth is an open-field vegetable crop consultant at Agrea. Growers today need to produce resilient onions that can stand up to extreme climate conditions, he says, with healthy, fertile soil, good manuring and well-chosen varieties, plus crop-specific measures. 

Ickenroth works mainly in the sandy area of the southeastern Netherlands, in Noord-Brabant and Limburg provinces. In recent years, Dutch onion production has been shifting to the east of the country, the consultant says, from the traditional growing regions in the southwest and areas reclaimed from the sea. 

On sandy soil, animal manure is generally applied before cultivation, Ickenroth says, and that’s fine for onions. “Animal manure is a reliable fertilizer here, certainly in dry years, and it also nourishes the soil life. And the organic matter present in slurry helps the organic matter balance, as long as the supply is greater than decomposition and drainage. The more organic matter the soil contains, the more moisture and nutrients it can retain.” 

To make optimum use of the minerals and moisture present in the soil, Ickenroth chooses varieties with a good root system, and preferably also foliage that isn’t too lush. “A well-developed root system can absorb moisture and minerals better and for longer, even in drier conditions. And a leaf apparatus that isn’t too strongly developed helps with the prevention and control of downy mildew.” 

Primed seed encourages fast, uniform emergence, Ickenroth adds. “Good early crop establishment is important, especially on sandy soil, to give the crop a head start so it can cope with drought and heat. Most parcels can be irrigated. This is increasingly done with a drip system. It’s an easy, user-friendly and, most of all, water-saving solution that positively affects the health of the onions. An onion that’s strong and grows well is essential for a healthy, profitable crop.” 

Peter Buysrogge 
Farmer, Emmeloord, the Netherlands 

The arable farmer Peter Buysrogge, based in the Dutch town of Emmeloord, doesn’t really believe in climate change. Every year is different, he says; the weather was sometimes dry or wet in the past. “Every year it’s something. No two years are the same. I grew Hysky for years because it was resistant to fusarium, but in the end I stopped. I get better yields from varieties with stronger rooting ability, so I’ve switched to Hyway. It’s also more suited to long-term storage.” 

Buysrogge has opted for primed Hyway because of the superior root system. “These onions do really well. The colour is nice and they’re super-firm. And primed Red Baron is just an old favourite. Fortunately, there were still enough anti-mildew products available this year. Now that mancozeb has been withdrawn, I’m wondering when resistance will be broken.” To fight onionfly, he’s used the Sterile Insect Technique for years; he gets it from a company called De Groene Vlieg. “It works as it should,” he says. “We never get told to spray.” 

  He mostly irrigates his onions using spring water. When the farm installed a spring water pump, it got rid of its screw pump, Peter says. “We’re seeing more and more screw pumps in the polder now, because the hardness of the draft water has got a lot lower. I used my neighbour’s screw pump to irrigate the onions once this season. To cope with rainy periods, we’ve made a lot of progress towards getting everything drained again.”