Growing Pains: A Dutch Grower Takes On Giant Pumpkins

Wezep is a small village in the Veluwe area of the Netherlands. And while it may not be a big place, the vegetables grown there are gigantic! Gerjan, a 21-year-old plant science student, took part in the Dutch Pumpkin Growing Championship at the end of September. In sharing his experience with us, we learned that growing giant veg is a lot of fun, but it also takes a lot of preparation!

How many giant pumpkins did you grow this season?

I started with eight plants, of which I ended up putting three into the ground; two outside and one in my greenhouse. Unfortunately, I had little success outside, as the pumpkins grew in bizarre shapes. They also only reached 100 kg. Luckily, I had more success in the greenhouse! One pumpkin grew to 635.5 kg and has been my best one so far. I even won the prize for the most beautiful pumpkin in The Netherlands. According to the jury, my pumpkin had the best color and shape and no (visible) signs of damage.

Have you been growing any other giant vegetables?

Yes, I also grew tomatoes, and I grew the largest one of all participants at 1843 grams! Unfortunately, I did not set a new personal record. I also grew sunflowers for the first time. I participated in the competition for the largest sunflower head and won third place.

What’s your secret to giant tomatoes?

Unlike giant pumpkins, which you can never really overfeed, a tomato is a little more particular. Well-balanced nutrition is critical. I mixed worm humus into the soil, and when the plants reached the growth phase, I started giving them Terra Grow, Power Roots, and Sugar Royal. That created the basis for a winner and is when the growth of the tomato started. When the first flowers appeared, I chose to remove all of them except for one. That way, the plant focused all its energy on one tomato. The plant’s food requirements also changed, so I switched to Terra Bloom. I continued giving the two additives and added Green Sensation to the mix. I also topped the plant and kept pruning suckers. After a month of growth, the tomato started coloring red. It was time to pick it and take it to be weighed.

Did you have to deal with any setbacks?

I guess you can say that’s an understatement! I’ve had quite a few setbacks this year. As I told you before, the pumpkins outside did not perform as expected. I had hoped to grow one of at least 600 kg there as well. The pumpkin in the greenhouse was the only one left at one point and developed mildew. In addition, I was bothered by mice, and for the first time, by spider mites. The mice even caused the pumpkin to rot.

What did you have to do differently this year to achieve good results still?

I discovered the issues above in time, so I intervened before it was too late. By slowing down the rotting process, I was able to limit the damage until weighing. I managed to do this with the help of grow specialists from Plagron. They gave me a really good piece of advice, namely to use hydrogen peroxide for disinfection. I also built a ventilation system in the greenhouse, giving the plant access to fresh and cool air. I used different Plagron nutrients and worked them through the soil initially and during the growth. The result was a pumpkin of 80 square meters!

Will you be participating again next year?

Sure thing! Next year, I will be aiming for a 700 kg pumpkin and try to grow some other giants. I have already started growing for the next pumpkin season.

Do you have an ultimate goal?

My ultimate goal changes all the time. The first time my goal was 100 kg, I went on to 250 kg and eventually 500 kg. My next goal is 700 kg, and once that is achieved, I’ll probably set another one. It has to be challenging every season!