It's not their main industry 1.6 % GDP (and that's including all agriculture) and only 2 percent of the active working population works there
Well yes, the Dutch are first. UK is sixth. So they are probably just better at it, no shame in that. They do subsidize, but they stay inside the EU competition rules concerning state aid et al.(quite stringent, resulted in some beautiful case law).
Some ways in which they help their industry:
https://www.rijksoverheid.nl/onderwerpen/landbouw-en-tuinbouw/landbouwsubsidies
https://www.agriholland.nl/subsidies/#tuinbouw
http://www.groentennieuws.nl/artikel/156631/Energie-subsidie-glastuinbouw-EHG-verlengd
You'll note that the big majority are in fact EU subsidies that are open for every one. The specific Dutch subsidies all meet the exceptions for when state aid is allowed. The U.K is free to do the same, and honestly it would surprise me if they didn't.
Any how; if you think that illegal state aid is taking place you can file a complaint with the European Commission and they will look at it and provide you with an extensive response:
Link:
http://ec.europa.eu/competition/forms/intro_en.html (the only thing that can be a bit tricky is proving that you are an interested party (as a natural person); but you can easily circumvent that by getting the UK horticultural organisation to do it for you.
This is not the EU's fault. The reason why this was able to continue is because
The United Kingdom, Sweden and the Netherlands were strongly opposed against EU measures to defend the internal market against the dumping. Only recently, around 26/02/2017, the EU was able to implement higher import duties against Chinese steel because they finally dropped their opposition.
I like windmills. There are 10 on +- 200-300 meters from my house. They aren't noisy; even if you stand next to them.
